Integrated hydrology updates

- Riverbed generation includes upstream shutdown fixes
Improved riverbed generation
2026-10-26 22:10:18 +00:00 · 2026-10-26 18:02:26 -04:00 · 2026-10-26 18:01:26 -04:00 · 2026-10-26 09:26:30 -06:00 · 2026-10-26 00:08:25 -04:00 · 2026-10-25 23:46:48 -04:00
1905 changed files with 157099 additions and 106606 deletions
@@ -1,87 +1,78 @@
-name: Iris Bug Report
-description: File a bug report for Iris
-labels: [ bug ]
+name: Bug report
+description: Something in Iris isn't working.
+labels: [bug]
+type: Bug
+assignees: [SwiftSwamp]
 body:
  - type: markdown
    attributes:
      value: |
-        Thank you for taking the time to fill this out!
-        If this does not work for you, feel free to use the [blank](https://github.com/VolmitSoftware/Iris/issues/new) format.
+        Make sure you're on the [latest release](https://github.com/VolmitSoftware/Iris/releases/latest) and that it hasn't [already been reported](https://github.com/VolmitSoftware/Iris/issues?q=is%3Aissue).
+
+        The Iris plugin supports Minecraft 26.1.2 through 26.3 on Paper, Purpur, Leaf, Canvas, Folia, and Spigot. The Fabric, Forge, and NeoForge builds support 26.3. Both need Java 25.
  - type: textarea
-    id: how
+    id: issue
    attributes:
-      label: Problem
-      description: Please give a text description of how you reached the problem
-      value: |
-        1. Install Iris...
-        2. Do this...
-        3. Do that...
-        4. Observe the error...
+      label: What issue are you having?
+      description: Include any error message you saw.
    validations:
      required: true
  - type: textarea
-    id: what
+    id: steps
    attributes:
-      label: Solution
-      description: Explain where you think the problem comes from (optional)
-      placeholder: The code to place a is missing b and c...
+      label: Steps to reproduce
+      placeholder: |
+        1. Start a server with Iris installed
+        2. Change ... in the config
+        3. Run /iris ...
+        4. ... happens instead of ...
    validations:
-      required: false
+      required: true
+  - type: input
+    id: diagnostics
+    attributes:
+      label: Debug dump or latest log file
+      description: Run `/iris debug dump upload=true` and paste the link. If Iris won't start, upload `logs/latest.log` to [mclo.gs](https://mclo.gs) and paste that link instead.
+      placeholder: https://mclo.gs/...
+    validations:
+      required: true
+  - type: input
+    id: plugin-version
+    attributes:
+      label: "Iris version"
+      description: Run `/iris debug version` (`/iris version` on Fabric, Forge, and NeoForge).
+    validations:
+      required: true
  - type: dropdown
    id: platform
    attributes:
-      label: Platform
-      description: Which server platform is Iris running on? Pick the loader or server software, not the launcher.
+      label: Server software
      options:
-        - Paper
-        - Purpur
-        - Leaf
-        - Canvas
-        - Folia
-        - Spigot / CraftBukkit
-        - Fabric
-        - Forge
-        - NeoForge
-        - Other (describe under Problem)
-    validations:
-      required: true
-  - type: dropdown
-    id: mcversion
-    attributes:
-      label: Minecraft Version
-      description: What version of Minecraft is the server on? Iris 4.x supports 26.1.2 to 26.3 on Bukkit-family servers and 26.3 on Fabric, Forge and NeoForge; older versions are not supported.
-      options:
-        - '26.3'
-        - '26.2'
-        - '26.1.2'
+        - "Paper"
+        - "Purpur"
+        - "Leaf"
+        - "Canvas"
+        - "Folia"
+        - "Spigot"
+        - "Fabric"
+        - "Forge"
+        - "NeoForge"
        - Other (unsupported)
    validations:
      required: true
-  - type: input
-    id: loaderversion
+  - type: dropdown
+    id: minecraft
    attributes:
-      label: Platform / Loader Version
-      description: Exact server or loader build (see console). For example "Paper 26.3-133", "Fabric Loader 0.19.5", "NeoForge 26.3.0.33-beta".
-      placeholder: DO NOT SAY "LATEST"
+      label: Minecraft version
+      options:
+        - "26.3"
+        - "26.2"
+        - "26.1.2"
+        - Other (unsupported)
    validations:
      required: true
-  - type: input
-    id: irisversion
+  - type: textarea
+    id: extra
    attributes:
-      label: Iris Version
-      description: What version of Iris are you running? (see console)
-      placeholder: DO NOT SAY "LATEST"
-    validations:
-      required: true
-  - type: input
-    id: logs
-    attributes:
-      label: Log
-      description: Paste a full log. Always use [mclogs](https://mclo.gs) Or [Pastebin](https://pastebin.com/). Must not be a crash report. Must be a full log. Must not be a screenshot of a log.
-      placeholder: https://mslog.gs/...
-    validations:
-      required: true
-  - type: markdown
-    id: thanks
-    attributes:
-      value: "Thank you for filling out the form! We will be with you soon. Please do not ask support to review your report."
+      label: Anything else?
+      description: Other plugins involved, screenshots, or videos.
@@ -0,0 +1,8 @@
+blank_issues_enabled: false
+contact_links:
+  - name: Help and questions
+    url: https://volmitsoftware.com/discord
+    about: Ask setup and configuration questions on the Volmit Discord.
+  - name: "Iris documentation"
+    url: https://docs.volmitsoftware.com/iris
+    about: Installation, commands, permissions, and configuration.
@@ -1,46 +1,28 @@
-name: Iris Feature Request
-description: File a feature request for Iris. If you want to report a bug this is not the place.
-labels: [ feature ]
+name: Suggestion
+description: Suggest a new feature or a change to Iris.
+labels: [enhancement]
+type: Feature
+assignees: [SwiftSwamp]
 body:
  - type: markdown
    attributes:
      value: |
-        Thank you for taking the time to fill this out!
-        If this does not work for you, feel free to use the [blank](https://github.com/VolmitSoftware/Iris/issues/new) format.
-  - type: dropdown
-    id: arc
+        Check the [existing suggestions](https://github.com/VolmitSoftware/Iris/issues?q=is%3Aissue+label%3Aenhancement) first and add relevant information to the existing issue.
+  - type: textarea
+    id: problem
    attributes:
-      label: Adding, Removing, or Changing
-      description: What are you doing
-      options:
-        - Adding
-        - Removing
-        - Changing
-    validations:
-      required: true
-  - type: input
-    id: atype
-    attributes:
-      label: Type of Modification
-      description: What is it for?
-      value: I want to ...
+      label: What are your suggestions for new features or changes?
    validations:
      required: true
  - type: textarea
-    id: desc
+    id: proposal
    attributes:
-      label: What are you trying to modify
-      description: Give as detailed of a description as you can for the modification that you want done (include pictures if applicable)
-      value: The way I would implement this is ...
+      label: How should it work?
+      description: Provide as much detail as possible on what you would like changed or added.
    validations:
      required: true
  - type: textarea
-    id: alternative
+    id: extra
    attributes:
-      label: Alternatives
-      description: What alternatives have you considered?
-      value: If this could not be implemented I would ...
-  - type: markdown
-    id: thanks
-    attributes:
-      value: "Thank you for filling out the form! We will be with you soon. Please do not ask support to review your report."
+      label: Anything else?
+      description: Any additional information such as screenshots, examples, etc.
@@ -0,0 +1,55 @@
+name: Translation
+description: A message in Iris is wrong, missing, or unclear.
+labels: [bug]
+type: Bug
+assignees: [SwiftSwamp]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        The language files are in [`core/src/main/resources/languages/`](https://github.com/VolmitSoftware/Iris/tree/HEAD/core/src/main/resources/languages).
+
+        You can create a pull request to modify the files directly.
+  - type: dropdown
+    id: language
+    attributes:
+      label: Language
+      options:
+        - English (en_US)
+        - German (de_DE)
+        - Spanish (es_ES)
+        - Finnish (fi_FI)
+        - French (fr_FR)
+        - Hebrew (he_IL)
+        - Italian (it_IT)
+        - Japanese (ja-JP)
+        - Korean (ko_KR)
+        - Lithuanian (lt_LT)
+        - Dutch (nl_NL)
+        - Polish (pl_PL)
+        - Portuguese (pt_PT)
+        - Russian (ru_RU)
+        - Turkish (tr_TR)
+        - Vietnamese (vi_VI)
+        - Chinese, Simplified (zh_CN)
+        - Chinese, Traditional (zh_TW)
+        - Another language (name it below)
+    validations:
+      required: true
+  - type: textarea
+    id: current
+    attributes:
+      label: Current text
+    validations:
+      required: true
+  - type: textarea
+    id: suggested
+    attributes:
+      label: Suggested text
+    validations:
+      required: true
+  - type: input
+    id: where
+    attributes:
+      label: Where does it appear?
+      description: The command used or message key where it is appearing.
@@ -0,0 +1,8 @@
+{
+  "name": "Iris",
+  "platform": "modded",
+  "versionProperty": "irisVersion",
+  "betaTag": "modded-beta",
+  "targets": "gradle/mod-targets.json",
+  "volmlibRef": "master"
+}
@@ -0,0 +1,327 @@
+import argparse
+import hashlib
+import json
+import os
+from pathlib import Path
+import re
+import sys
+import tomllib
+import urllib.error
+import urllib.parse
+import urllib.request
+import zipfile
+
+
+def read_config(root: Path) -> dict:
+    return json.loads((root / '.github/release.json').read_text())
+
+
+def targets(root: Path, config: dict) -> list[dict[str, str]]:
+    if config['platform'] == 'bukkit':
+        return [{'id': 'bukkit', 'loader': 'bukkit', 'minecraft': ''}]
+    manifest: Path = root / config['targets']
+    if manifest.is_file():
+        versions: dict = json.loads(manifest.read_text())
+        entries: list[tuple[str, list[str]]] = [(version, ['fabric', 'forge', 'neoforge']) for version in versions]
+    else:
+        entries = []
+        for path in sorted(manifest.glob('*.json')):
+            target: dict = json.loads(path.read_text())
+            if path.stem != target['minecraft']:
+                raise ValueError(f'Minecraft manifest does not match {path.name}')
+            entries.append((target['minecraft'], list(target['loaders'])))
+    matrix: list[dict[str, str]] = []
+    for version, loaders in entries:
+        if not re.fullmatch(r'[0-9]+(?:\.[0-9]+)+', version):
+            raise ValueError(f'Invalid Minecraft version: {version}')
+        if set(loaders) != {'fabric', 'forge', 'neoforge'}:
+            raise ValueError(f'Incomplete loader matrix for {version}')
+        for loader in sorted(loaders):
+            matrix.append({'id': f'{loader}-{version}', 'loader': loader, 'minecraft': version})
+    if not matrix:
+        raise ValueError('Release matrix is empty')
+    return matrix
+
+
+def plan(root: Path, config: dict, event: dict, environment: dict) -> dict:
+    branch: str = event.get('repository', {}).get('default_branch', '')
+    if (environment.get('GITHUB_EVENT_NAME') != 'push' or event.get('deleted')
+            or not branch or event.get('ref') != f'refs/heads/{branch}'):
+        return {'channel': 'none'}
+    commit: dict = event.get('head_commit') or {}
+    message: str = commit.get('message', '')
+    beta: bool = 'B+' in message
+    stable: bool = 'V+' in message
+    if beta and stable:
+        raise ValueError('Use exactly one release marker: B+ or V+')
+    if not beta and not stable:
+        return {'channel': 'none'}
+    sha: str = environment['GITHUB_SHA']
+    if event.get('after') != sha or commit.get('id') != sha or not re.fullmatch(r'[a-f0-9]{40}', sha):
+        raise ValueError('Release commit does not match the pushed HEAD')
+    key: str = config['versionProperty']
+    properties: str = (root / 'gradle.properties').read_text()
+    values: list[str] = re.findall(rf'^{re.escape(key)}\s*=\s*(\S+)\s*$', properties, re.MULTILINE)
+    if len(values) != 1 or not re.fullmatch(r'(0|[1-9][0-9]*)\.(0|[1-9][0-9]*)\.(0|[1-9][0-9]*)', values[0]):
+        raise ValueError(f'{key} must declare one stable major.minor.patch version')
+    run: int = int(environment['GITHUB_RUN_NUMBER'])
+    attempt: int = int(environment['GITHUB_RUN_ATTEMPT'])
+    if run < 1 or attempt < 1:
+        raise ValueError('Invalid workflow run identity')
+    version: str = f'{values[0]}-beta.{run}.{attempt}' if beta else values[0]
+    return {
+        'channel': 'beta' if beta else 'stable',
+        'version': version,
+        'version_property': key,
+        'tag': config['betaTag'] if beta else f'v{version}',
+        'sha': sha,
+        'run': run,
+        'attempt': attempt,
+        'matrix': {'include': targets(root, config)},
+        'volmlib_ref': config['volmlibRef'],
+        'wormholes_ref': config.get('wormholesRef', ''),
+    }
+
+
+def collect_artifacts(directory: Path, release: dict) -> dict[str, bytes]:
+    expected: dict[str, dict] = {f"release-{entry['id']}": entry for entry in release['matrix']['include']}
+    if {path.name for path in directory.iterdir()} != set(expected):
+        raise ValueError('Downloaded artifacts do not match the complete release matrix')
+    assets: dict[str, bytes] = {}
+    descriptors: dict[str, str] = {'bukkit': 'plugin.yml', 'fabric': 'fabric.mod.json',
+                                  'forge': 'META-INF/mods.toml', 'neoforge': 'META-INF/neoforge.mods.toml'}
+    for name, target in expected.items():
+        folder: Path = directory / name
+        paths: list[Path] = list(folder.iterdir()) if folder.is_dir() and not folder.is_symlink() else []
+        if len(paths) != 1 or paths[0].suffix != '.jar' or paths[0].is_symlink() or not paths[0].is_file():
+            raise ValueError(f'{name} must contain exactly one runtime jar')
+        path: Path = paths[0]
+        loader: str = target['loader']
+        suffix: str = re.escape(release['version']) + r'-bukkit\.jar'
+        if loader != 'bukkit':
+            display: str = {'fabric': 'Fabric', 'forge': 'Forge', 'neoforge': 'NeoForge'}[loader]
+            suffix = (r'v' + re.escape(release['version']) + r' \[' + display + r'\] '
+                      + re.escape(target['minecraft']) + r'\+[^/\s]+\.jar')
+        if not re.fullmatch(r'[A-Za-z][A-Za-z0-9]*' + ('-' if loader == 'bukkit' else ' ') + suffix, path.name):
+            raise ValueError(f'Artifact does not match the release target: {path.name}')
+        with zipfile.ZipFile(path) as archive:
+            entries: set[str] = set(archive.namelist())
+            descriptor: str = descriptors[target['loader']]
+            if descriptor not in entries:
+                raise ValueError(f'{path.name} is missing {descriptor}')
+            excluded: set[str] = set(descriptors.values()) - {descriptor}
+            if 'velocity-plugin.json' in entries or entries.intersection(excluded):
+                raise ValueError(f'{path.name} contains an excluded platform')
+            contents: str = archive.read(descriptor).decode()
+            if loader == 'bukkit':
+                match: re.Match | None = re.search(r'^version:\s*[\'\"]?([^\s\'\"]+)', contents, re.MULTILINE)
+                version: str | None = match[1] if match else None
+            elif loader == 'fabric':
+                metadata: dict = json.loads(contents)
+                version = metadata.get('version')
+                if metadata.get('depends', {}).get('minecraft') not in (target['minecraft'], '~' + target['minecraft']):
+                    raise ValueError(f'{path.name} declares a different Minecraft target')
+            else:
+                metadata = tomllib.loads(contents)
+                mods: list[dict] = metadata.get('mods', [])
+                version = mods[0].get('version') if len(mods) == 1 else None
+                dependencies: list[dict] = metadata.get('dependencies', {}).get(mods[0].get('modId'), []) if len(mods) == 1 else []
+                minecraft: list[str] = [entry.get('versionRange') for entry in dependencies if entry.get('modId') == 'minecraft']
+                if minecraft != ['[' + target['minecraft'] + ']']:
+                    raise ValueError(f'{path.name} declares a different Minecraft target')
+            if version != release['version']:
+                raise ValueError(f'{path.name} declares a different product version')
+        asset_name: str = re.sub(r'[^A-Za-z0-9._-]+', '-', path.name)
+        if asset_name in assets:
+            raise ValueError(f'Duplicate release asset: {asset_name}')
+        assets[asset_name] = path.read_bytes()
+    checksums: str = ''.join(f'{hashlib.sha256(data).hexdigest()}  {name}\n' for name, data in sorted(assets.items()))
+    assets[f"SHA256SUMS-{release['version']}.txt"] = checksums.encode()
+    return assets
+
+
+class GitHub:
+    def __init__(self, repository: str, token: str):
+        if not re.fullmatch(r'[A-Za-z0-9_.-]+/[A-Za-z0-9_.-]+', repository):
+            raise ValueError('Invalid GitHub repository')
+        self.repository = repository
+        self.token = token
+
+    def request(self, method: str, path: str, payload: dict | bytes | None = None, missing: bool = False) -> dict | list | None:
+        url: str = path if path.startswith('https://uploads.github.com/') else f'https://api.github.com/repos/{self.repository}/{path}'
+        binary: bool = isinstance(payload, bytes)
+        data: bytes | None = payload if binary else json.dumps(payload).encode() if payload is not None else None
+        request: urllib.request.Request = urllib.request.Request(url, data=data, method=method, headers={
+            'Authorization': f'Bearer {self.token}',
+            'Accept': 'application/vnd.github+json',
+            'X-GitHub-Api-Version': '2026-03-10',
+            'Content-Type': 'application/octet-stream' if binary else 'application/json',
+            'User-Agent': 'Volmit-release',
+        })
+        try:
+            with urllib.request.urlopen(request, timeout=120) as response:
+                body: bytes = response.read()
+                return json.loads(body) if body else None
+        except urllib.error.HTTPError as error:
+            if missing and error.code == 404:
+                return None
+            raise RuntimeError(f'GitHub {method} {urllib.parse.urlsplit(url).path}: HTTP {error.code}') from error
+
+    def tag_commit(self, tag: str) -> str | None:
+        reference: dict | None = self.request('GET', f'git/ref/tags/{tag}', missing=True)
+        if reference is None:
+            return None
+        target: dict = reference['object']
+        for _ in range(8):
+            if target['type'] == 'commit':
+                return target['sha']
+            if target['type'] != 'tag':
+                break
+            target = self.request('GET', f"git/tags/{target['sha']}")['object']
+        raise ValueError(f'{tag} does not resolve to a commit')
+
+    def assets(self, release_id: int) -> list[dict]:
+        result: list[dict] = []
+        page: int = 1
+        while True:
+            batch: list[dict] = self.request('GET', f'releases/{release_id}/assets?per_page=100&page={page}')
+            result.extend(batch)
+            if len(batch) < 100:
+                return result
+            page += 1
+
+
+def resolve_dependency(repository: str, reference: str, token: str) -> str:
+    commit: dict = GitHub(repository, token).request('GET', f'commits/{urllib.parse.quote(reference, safe="")}')
+    sha: str = commit['sha']
+    if not re.fullmatch(r'[a-f0-9]{40}', sha):
+        raise ValueError(f'{repository} did not resolve to a commit')
+    return sha
+
+
+def release_metadata(existing: dict) -> dict:
+    match: re.Match | None = re.search(r'<!-- release: (.+) -->', existing.get('body') or '')
+    if match is None:
+        raise ValueError('Existing release has no publication identity; refusing to overwrite it')
+    return json.loads(match[1])
+
+
+def verify_assets(existing: list[dict], assets: dict[str, bytes]) -> bool:
+    return {entry['name']: entry.get('digest') for entry in existing} == {
+        name: 'sha256:' + hashlib.sha256(data).hexdigest() for name, data in assets.items()}
+
+
+def publish(github: GitHub, config: dict, release: dict, assets: dict[str, bytes]) -> str:
+    tag: str = release['tag']
+    beta: bool = release['channel'] == 'beta'
+    existing: dict | None = github.request('GET', f'releases/tags/{tag}', missing=True)
+    commit: str | None = github.tag_commit(tag)
+    if not beta and commit is not None and commit != release['sha']:
+        raise ValueError(f'{tag} already points to another commit')
+    if existing is not None:
+        metadata: dict = release_metadata(existing)
+        if bool(existing['prerelease']) != beta:
+            raise ValueError('Existing release belongs to a different release channel')
+        if beta and (metadata['run'], metadata['attempt']) > (release['run'], release['attempt']):
+            return 'Skipped older beta run'
+        if not beta and metadata['sha'] != release['sha']:
+            raise ValueError('Stable release belongs to another commit')
+        if not existing['draft'] and commit == release['sha'] and metadata['version'] == release['version']:
+            if verify_assets(github.assets(existing['id']), assets):
+                return 'Release already published with identical artifacts'
+            if not beta:
+                raise ValueError('Published release artifacts differ; refusing to overwrite them')
+        if existing.get('immutable'):
+            raise ValueError('Rolling beta requires mutable releases in repository settings')
+        if not beta and not existing['draft']:
+            raise ValueError('Stable release is already published')
+    elif beta and commit is not None:
+        raise ValueError('Beta tag exists without a release; refusing to move it')
+    identity: dict = {key: release[key] for key in ('version', 'sha', 'run', 'attempt', 'volmlib_ref', 'wormholes_ref') if key in release}
+    platform: str = 'Modded' if config['platform'] == 'modded' else 'CraftBukkit'
+    body: str = (f"{platform} jars for {config['name']} {release['version']}.\n\n"
+                 f"Commit: `{release['sha']}`\n\n"
+                 f"<!-- release: {json.dumps(identity, sort_keys=True)} -->")
+    attributes: dict = {
+        'tag_name': tag, 'target_commitish': release['sha'],
+        'name': f"{config['name']} {platform} {'Beta' if beta else release['version']}",
+        'body': body, 'prerelease': beta, 'make_latest': 'false',
+    }
+    if existing is None:
+        existing = github.request('POST', 'releases', {**attributes, 'draft': True})
+    elif beta:
+        existing = github.request('PATCH', f"releases/{existing['id']}", {**attributes, 'draft': True})
+    uploaded: list[dict] = github.assets(existing['id'])
+    by_name: dict[str, dict] = {entry['name']: entry for entry in uploaded}
+    for name, data in assets.items():
+        digest: str = 'sha256:' + hashlib.sha256(data).hexdigest()
+        if name in by_name:
+            if by_name[name].get('state') == 'starter':
+                github.request('DELETE', f"releases/assets/{by_name[name]['id']}")
+            elif by_name[name].get('digest') != digest:
+                raise ValueError(f'Existing asset differs: {name}')
+            else:
+                continue
+        upload_url: str = existing['upload_url'].split('{')[0] + '?' + urllib.parse.urlencode({'name': name})
+        receipt: dict = github.request('POST', upload_url, data)
+        if receipt.get('digest') != digest or receipt['name'] != name:
+            raise ValueError(f'Upload verification failed: {name}')
+    for entry in uploaded:
+        if entry['name'] not in assets:
+            github.request('DELETE', f"releases/assets/{entry['id']}")
+    commit = github.tag_commit(tag)
+    if commit is None:
+        github.request('POST', 'git/refs', {'ref': f'refs/tags/{tag}', 'sha': release['sha']})
+    elif commit != release['sha']:
+        if not beta:
+            raise ValueError('Stable tag changed during publication')
+        github.request('PATCH', f'git/refs/tags/{tag}', {'sha': release['sha'], 'force': True})
+    if not beta and config['platform'] == 'bukkit':
+        latest: dict | None = github.request('GET', 'releases/latest', missing=True)
+        match: re.Match | None = re.match(r'^v?(\d+)\.(\d+)\.(\d+)(?:$|-)', latest['tag_name']) if latest else None
+        if latest is None or (match and tuple(map(int, release['version'].split('.'))) > tuple(map(int, match.groups()))):
+            attributes['make_latest'] = 'true'
+    github.request('PATCH', f"releases/{existing['id']}", {**attributes, 'draft': False})
+    return f"Published {tag} at {release['sha']}"
+
+
+def main() -> None:
+    parser: argparse.ArgumentParser = argparse.ArgumentParser()
+    parser.add_argument('command', choices=['plan', 'publish'])
+    parser.add_argument('--artifacts', type=Path)
+    arguments: argparse.Namespace = parser.parse_args()
+    root: Path = Path(__file__).resolve().parent.parent
+    config: dict = read_config(root)
+    event: dict = json.loads(Path(os.environ['GITHUB_EVENT_PATH']).read_text())
+    environment: dict = dict(os.environ)
+    if arguments.command == 'publish':
+        environment['GITHUB_RUN_ATTEMPT'] = environment['RELEASE_ATTEMPT']
+    release: dict = plan(root, config, event, environment)
+    if arguments.command == 'plan':
+        if release['channel'] != 'none':
+            release['volmlib_ref'] = resolve_dependency('VolmitSoftware/VolmLib', config['volmlibRef'], environment['GH_TOKEN'])
+            if release['wormholes_ref']:
+                release['wormholes_ref'] = resolve_dependency('VolmitSoftware/Wormholes', config['wormholesRef'], environment['GH_TOKEN'])
+        with Path(os.environ['GITHUB_OUTPUT']).open('a') as output:
+            for key, value in release.items():
+                output.write(f'{key}={json.dumps(value, separators=(",", ":")) if isinstance(value, dict) else value}\n')
+        print(f"Release channel: {release['channel']}")
+    elif release['channel'] != 'none':
+        if arguments.artifacts is None:
+            raise ValueError('Publication requires the complete artifact directory')
+        for key in ('volmlib_ref', 'wormholes_ref'):
+            if release[key]:
+                resolved: str = environment[f'RELEASE_{key.upper()}']
+                if not re.fullmatch(r'[a-f0-9]{40}', resolved):
+                    raise ValueError(f'{key} is not a resolved dependency commit')
+                release[key] = resolved
+        github: GitHub = GitHub(os.environ['GITHUB_REPOSITORY'], os.environ['GH_TOKEN'])
+        print(publish(github, config, release, collect_artifacts(arguments.artifacts, release)))
+
+
+if __name__ == '__main__':
+    try:
+        main()
+    except (ValueError, RuntimeError) as error:
+        print(f'::error::{error}', file=sys.stderr)
+        sys.exit(1)
@@ -0,0 +1,718 @@
+import copy
+import hashlib
+import importlib.util
+import io
+import json
+from pathlib import Path
+import tempfile
+import unittest
+from unittest.mock import patch
+import urllib.parse
+import zipfile
+
+
+SPEC = importlib.util.spec_from_file_location('release', Path(__file__).with_name('release.py'))
+release = importlib.util.module_from_spec(SPEC)
+SPEC.loader.exec_module(release)
+
+SHA = 'a' * 40
+OTHER_SHA = 'b' * 40
+
+
+def digest(data: bytes) -> str:
+    return 'sha256:' + hashlib.sha256(data).hexdigest()
+
+
+class FakeGitHub:
+    def __init__(self) -> None:
+        self.tags: dict[str, str] = {}
+        self.releases: dict[int, dict] = {}
+        self.uploads: dict[int, dict[str, dict]] = {}
+        self.writes: list[tuple[str, str]] = []
+        self.latest: dict | None = None
+        self.fail_upload: str | None = None
+        self.fail_delete: int | None = None
+        self.invalid_receipt: bool = False
+        self.next_asset: int = 1
+
+    def seed(self, publication: dict, assets: dict[str, bytes], draft: bool = False,
+             immutable: bool = False) -> dict:
+        identity: dict = {key: publication[key] for key in ('sha', 'version', 'run', 'attempt')}
+        record: dict = {
+            'id': len(self.releases) + 1,
+            'tag_name': publication['tag'],
+            'body': '<!-- release: ' + json.dumps(identity) + ' -->',
+            'draft': draft,
+            'prerelease': publication['channel'] == 'beta',
+            'immutable': immutable,
+        }
+        record['upload_url'] = f"https://uploads.github.com/repos/example/product/releases/{record['id']}/assets{{?name,label}}"
+        self.releases[record['id']] = record
+        self.uploads[record['id']] = {}
+        for name, data in assets.items():
+            self.add_asset(record['id'], name, data)
+        self.tags[publication['tag']] = publication['sha']
+        return record
+
+    def add_asset(self, identifier: int, name: str, data: bytes) -> dict:
+        receipt: dict = {'id': self.next_asset, 'name': name, 'digest': digest(data)}
+        self.next_asset += 1
+        self.uploads[identifier][name] = receipt
+        return copy.deepcopy(receipt)
+
+    def tag_commit(self, tag: str) -> str | None:
+        return self.tags.get(tag)
+
+    def assets(self, identifier: int) -> list[dict]:
+        return copy.deepcopy(list(self.uploads[identifier].values()))
+
+    def request(self, method: str, path: str, payload: dict | bytes | None = None,
+                missing: bool = False) -> dict | list | None:
+        if method != 'GET':
+            self.writes.append((method, path))
+        if method == 'GET' and path.startswith('releases/tags/'):
+            tag: str = path.removeprefix('releases/tags/')
+            return copy.deepcopy(next((record for record in self.releases.values()
+                                       if record['tag_name'] == tag), None))
+        if method == 'GET' and path == 'releases/latest':
+            return copy.deepcopy(self.latest)
+        if method == 'POST' and path == 'releases':
+            identifier: int = len(self.releases) + 1
+            record: dict = copy.deepcopy(payload)
+            record.update({'id': identifier, 'immutable': False,
+                           'upload_url': f'https://uploads.github.com/repos/example/product/releases/{identifier}/assets{{?name,label}}'})
+            self.releases[identifier] = record
+            self.uploads[identifier] = {}
+            return copy.deepcopy(record)
+        if method == 'POST' and path.startswith('https://uploads.github.com/'):
+            address: urllib.parse.SplitResult = urllib.parse.urlsplit(path)
+            name: str = urllib.parse.parse_qs(address.query)['name'][0]
+            if name == self.fail_upload:
+                raise RuntimeError('Upload unavailable')
+            identifier: int = int(address.path.split('/')[-2])
+            receipt: dict = self.add_asset(identifier, name, payload)
+            if self.invalid_receipt:
+                receipt['digest'] = digest(b'corrupted')
+            return receipt
+        if method == 'POST' and path == 'git/refs':
+            tag: str = payload['ref'].removeprefix('refs/tags/')
+            if tag in self.tags:
+                raise RuntimeError('Tag already exists')
+            self.tags[tag] = payload['sha']
+            return {'object': {'type': 'commit', 'sha': payload['sha']}}
+        if method == 'PATCH' and path.startswith('git/refs/tags/'):
+            self.tags[path.removeprefix('git/refs/tags/')] = payload['sha']
+            return None
+        if method == 'DELETE' and path.startswith('releases/assets/'):
+            identifier: int = int(path.rsplit('/', 1)[1])
+            if identifier == self.fail_delete:
+                raise RuntimeError('Delete unavailable')
+            for uploaded in self.uploads.values():
+                for name, entry in list(uploaded.items()):
+                    if entry['id'] == identifier:
+                        del uploaded[name]
+                        return None
+            raise AssertionError(f'Unknown asset: {identifier}')
+        if method == 'PATCH' and path.startswith('releases/'):
+            identifier: int = int(path.rsplit('/', 1)[1])
+            self.releases[identifier].update(copy.deepcopy(payload))
+            if payload.get('make_latest') == 'true':
+                self.latest = copy.deepcopy(self.releases[identifier])
+            return copy.deepcopy(self.releases[identifier])
+        raise AssertionError(f'Unexpected API request: {method} {path}')
+
+
+class ReleaseTestCase(unittest.TestCase):
+    def setUp(self) -> None:
+        temporary: tempfile.TemporaryDirectory = tempfile.TemporaryDirectory()
+        self.addCleanup(temporary.cleanup)
+        self.root: Path = Path(temporary.name)
+        self.config: dict = {'name': 'Example', 'platform': 'bukkit', 'versionProperty': 'exampleVersion',
+                             'betaTag': 'bukkit-beta', 'volmlibRef': 'c' * 40}
+        (self.root / 'gradle.properties').write_text('exampleVersion=1.2.3\n')
+        self.event: dict = {'repository': {'default_branch': 'main'}, 'ref': 'refs/heads/main',
+                            'after': SHA, 'head_commit': {'id': SHA, 'message': 'V+ Publish'}}
+        self.environment: dict = {'GITHUB_EVENT_NAME': 'push', 'GITHUB_SHA': SHA,
+                                  'GITHUB_RUN_NUMBER': '17', 'GITHUB_RUN_ATTEMPT': '2'}
+        network = patch.object(release.urllib.request, 'urlopen', side_effect=AssertionError('Network is forbidden'))
+        network.start()
+        self.addCleanup(network.stop)
+
+    def publication(self, channel: str = 'stable', **changes) -> dict:
+        result: dict = {
+            'channel': channel, 'version': '1.2.3-beta.17.2' if channel == 'beta' else '1.2.3',
+            'tag': 'bukkit-beta' if channel == 'beta' else 'v1.2.3', 'sha': SHA, 'run': 17, 'attempt': 2,
+            'matrix': {'include': [{'id': 'bukkit', 'loader': 'bukkit', 'minecraft': ''}]},
+        }
+        result.update(changes)
+        return result
+
+    def matrix(self, versions: tuple[str, ...] = ('1.20.1', '1.21.1')) -> list[dict]:
+        return [{'id': f'{loader}-{version}', 'loader': loader, 'minecraft': version}
+                for version in versions for loader in ('fabric', 'forge', 'neoforge')]
+
+    def artifact_tree(self, publication: dict, extra: tuple[str, ...] = ()) -> Path:
+        directory: Path = self.root / 'artifacts'
+        directory.mkdir(exist_ok=True)
+        descriptors: dict[str, str] = {'bukkit': 'plugin.yml', 'fabric': 'fabric.mod.json',
+                                      'forge': 'META-INF/mods.toml', 'neoforge': 'META-INF/neoforge.mods.toml'}
+        for target in publication['matrix']['include']:
+            folder: Path = directory / f"release-{target['id']}"
+            folder.mkdir()
+            loader: str = target['loader']
+            if loader == 'bukkit':
+                filename: str = f"Example-{publication['version']}-bukkit.jar"
+                metadata: str = f"name: Example\nversion: {publication['version']}\nmain: example.Plugin\n"
+            else:
+                display: str = {'fabric': 'Fabric', 'forge': 'Forge', 'neoforge': 'NeoForge'}[loader]
+                filename = f"Example v{publication['version']} [{display}] {target['minecraft']}+1.0.0.jar"
+                if loader == 'fabric':
+                    metadata = json.dumps({'schemaVersion': 1, 'id': 'example', 'version': publication['version'],
+                                           'depends': {'minecraft': '~' + target['minecraft']}})
+                else:
+                    metadata = (f"modLoader = 'javafml'\nloaderVersion = '[1,)'\nlicense = 'MIT'\n"
+                                f"[[mods]]\nmodId = 'example'\nversion = '{publication['version']}'\n"
+                                f"[[dependencies.example]]\nmodId = 'minecraft'\n"
+                                f"versionRange = '[{target['minecraft']}]'\n")
+            path: Path = folder / filename
+            with zipfile.ZipFile(path, 'w') as archive:
+                archive.writestr(descriptors[loader], metadata)
+                for name in extra:
+                    archive.writestr(name, '')
+        return directory
+
+
+class PlanTests(ReleaseTestCase):
+    def test_markers_are_case_sensitive(self) -> None:
+        for message, channel in [('B+ Beta', 'beta'), ('V+ Release', 'stable'),
+                                 ('b+ beta', 'none'), ('v+ release', 'none'), ('Fix a bug', 'none')]:
+            with self.subTest(message=message):
+                self.event['head_commit']['message'] = message
+                result: dict = release.plan(self.root, self.config, self.event, self.environment)
+                self.assertEqual(channel, result['channel'])
+                if channel == 'beta':
+                    self.assertEqual('1.2.3-beta.17.2', result['version'])
+                    self.assertEqual('bukkit-beta', result['tag'])
+                elif channel == 'stable':
+                    self.assertEqual('1.2.3', result['version'])
+                    self.assertEqual('v1.2.3', result['tag'])
+
+    def test_both_markers_fail(self) -> None:
+        self.event['head_commit']['message'] = 'B+ first\nV+ second'
+        with self.assertRaises(ValueError):
+            release.plan(self.root, self.config, self.event, self.environment)
+
+    def test_only_pushed_default_branch_head_can_release(self) -> None:
+        cases: list[tuple[dict, dict]] = [
+            ({'ref': 'refs/heads/feature'}, {}), ({'ref': 'refs/tags/V+1.2.3'}, {}),
+            ({'deleted': True}, {}), ({'repository': {}}, {}),
+            ({'head_commit': None}, {}), ({}, {'GITHUB_EVENT_NAME': 'pull_request'}),
+        ]
+        for event_changes, environment_changes in cases:
+            with self.subTest(event=event_changes, environment=environment_changes):
+                self.assertEqual({'channel': 'none'}, release.plan(
+                    self.root, self.config, {**self.event, **event_changes},
+                    {**self.environment, **environment_changes}))
+
+    def test_head_identity_must_match_event_and_environment(self) -> None:
+        for field in ('after', 'commit', 'environment'):
+            with self.subTest(field=field):
+                event: dict = copy.deepcopy(self.event)
+                environment: dict = self.environment.copy()
+                if field == 'commit':
+                    event['head_commit']['id'] = OTHER_SHA
+                elif field == 'environment':
+                    environment['GITHUB_SHA'] = 'not-a-sha'
+                else:
+                    event['after'] = OTHER_SHA
+                with self.assertRaises(ValueError):
+                    release.plan(self.root, self.config, event, environment)
+
+    def test_old_commits_do_not_trigger_release(self) -> None:
+        self.event['commits'] = [{'id': OTHER_SHA, 'message': 'V+ Release'}]
+        self.event['head_commit']['message'] = 'Fix a bug'
+        self.assertEqual({'channel': 'none'}, release.plan(self.root, self.config, self.event, self.environment))
+
+    def test_invalid_or_duplicate_versions_fail(self) -> None:
+        for value in ('', 'exampleVersion=01.2.3\n', 'exampleVersion=1.2\n',
+                      'exampleVersion=1.2.3-beta.1\n', 'exampleVersion=1.2.3\nexampleVersion=2.3.4\n'):
+            with self.subTest(value=value):
+                (self.root / 'gradle.properties').write_text(value)
+                with self.assertRaises(ValueError):
+                    release.plan(self.root, self.config, self.event, self.environment)
+
+    def test_invalid_run_identity_fails(self) -> None:
+        for key in ('GITHUB_RUN_NUMBER', 'GITHUB_RUN_ATTEMPT'):
+            with self.subTest(key=key), self.assertRaises(ValueError):
+                release.plan(self.root, self.config, self.event, {**self.environment, key: '0'})
+
+    def test_minecraft_file_matrix_contains_all_loaders(self) -> None:
+        (self.root / 'targets.json').write_text(json.dumps({'1.20.1': {}, '1.21.1': {}}))
+        config: dict = {**self.config, 'platform': 'modded', 'targets': 'targets.json'}
+        self.assertEqual(self.matrix(), release.targets(self.root, config))
+
+    def test_minecraft_directory_matrix_matches_files(self) -> None:
+        folder: Path = self.root / 'targets'
+        folder.mkdir()
+        (folder / '1.20.1.json').write_text(json.dumps({'minecraft': '1.20.1',
+                                                      'loaders': ['fabric', 'forge', 'neoforge']}))
+        config: dict = {**self.config, 'platform': 'modded', 'targets': 'targets'}
+        self.assertEqual(self.matrix(('1.20.1',)), release.targets(self.root, config))
+        for minecraft, loaders in [('1.20.2', ['fabric', 'forge', 'neoforge']), ('1.20.1', ['fabric'])]:
+            with self.subTest(minecraft=minecraft, loaders=loaders):
+                (folder / '1.20.1.json').write_text(json.dumps({'minecraft': minecraft, 'loaders': loaders}))
+                with self.assertRaises(ValueError):
+                    release.targets(self.root, config)
+
+    def test_empty_or_invalid_minecraft_matrix_fails(self) -> None:
+        for content in ({}, {'invalid': {}}):
+            with self.subTest(content=content):
+                (self.root / 'targets.json').write_text(json.dumps(content))
+                with self.assertRaises(ValueError):
+                    release.targets(self.root, {**self.config, 'platform': 'modded', 'targets': 'targets.json'})
+
+
+class ArtifactTests(ReleaseTestCase):
+    def test_complete_modded_matrix_and_checksums(self) -> None:
+        publication: dict = self.publication(matrix={'include': self.matrix()})
+        assets: dict[str, bytes] = release.collect_artifacts(self.artifact_tree(publication), publication)
+        self.assertEqual(7, len(assets))
+        checksums: bytes = assets.pop('SHA256SUMS-1.2.3.txt')
+        self.assertEqual(''.join(f'{hashlib.sha256(data).hexdigest()}  {name}\n'
+                                 for name, data in sorted(assets.items())).encode(), checksums)
+
+    def test_missing_or_extra_matrix_target_fails(self) -> None:
+        publication: dict = self.publication()
+        directory: Path = self.artifact_tree(publication)
+        (directory / 'release-extra').mkdir()
+        with self.assertRaises(ValueError):
+            release.collect_artifacts(directory, publication)
+        (directory / 'release-extra').rmdir()
+        (directory / 'release-bukkit').rename(directory / 'release-wrong')
+        with self.assertRaises(ValueError):
+            release.collect_artifacts(directory, publication)
+
+    def test_intermediate_artifact_beside_runtime_fails(self) -> None:
+        publication: dict = self.publication()
+        directory: Path = self.artifact_tree(publication)
+        (directory / 'release-bukkit' / 'sources.jar').write_bytes(b'sources')
+        with self.assertRaises(ValueError):
+            release.collect_artifacts(directory, publication)
+
+    def test_symbolic_link_artifacts_fail(self) -> None:
+        publication: dict = self.publication()
+        directory: Path = self.artifact_tree(publication)
+        path: Path = next((directory / 'release-bukkit').iterdir())
+        target: Path = self.root / path.name
+        path.rename(target)
+        path.symlink_to(target)
+        with self.assertRaises(ValueError):
+            release.collect_artifacts(directory, publication)
+
+    def test_bukkit_is_forbidden_in_modded_release(self) -> None:
+        publication: dict = self.publication(matrix={'include': self.matrix(('1.20.1',))})
+        with self.assertRaises(ValueError):
+            release.collect_artifacts(self.artifact_tree(publication, ('plugin.yml',)), publication)
+
+    def test_velocity_is_forbidden_in_bukkit_release(self) -> None:
+        publication: dict = self.publication()
+        with self.assertRaises(ValueError):
+            release.collect_artifacts(self.artifact_tree(publication, ('velocity-plugin.json',)), publication)
+
+    def test_modded_descriptor_is_forbidden_in_bukkit_release(self) -> None:
+        publication: dict = self.publication()
+        with self.assertRaises(ValueError):
+            release.collect_artifacts(self.artifact_tree(publication, ('fabric.mod.json',)), publication)
+
+    def test_required_platform_descriptor_is_checked(self) -> None:
+        publication: dict = self.publication()
+        directory: Path = self.artifact_tree(publication)
+        path: Path = next((directory / 'release-bukkit').iterdir())
+        with zipfile.ZipFile(path, 'w') as archive:
+            archive.writestr('fabric.mod.json', '{}')
+        with self.assertRaises(ValueError):
+            release.collect_artifacts(directory, publication)
+
+    def test_wrong_version_and_embedded_version_suffix_fail(self) -> None:
+        publication: dict = self.publication()
+        directory: Path = self.artifact_tree(publication)
+        path: Path = next((directory / 'release-bukkit').iterdir())
+        for version in ('9.8.7', '11.2.3'):
+            with self.subTest(version=version):
+                changed: Path = path.with_name(f'Example-{version}-bukkit.jar')
+                path.rename(changed)
+                with self.assertRaises(ValueError):
+                    release.collect_artifacts(directory, publication)
+                changed.rename(path)
+
+    def test_descriptor_version_must_match_release(self) -> None:
+        publication: dict = self.publication()
+        directory: Path = self.artifact_tree(publication)
+        path: Path = next((directory / 'release-bukkit').iterdir())
+        with zipfile.ZipFile(path, 'w') as archive:
+            archive.writestr('plugin.yml', 'name: Example\nversion: 1.2.4\nmain: example.Plugin\n')
+        with self.assertRaises(ValueError):
+            release.collect_artifacts(directory, publication)
+
+    def test_modded_descriptor_versions_must_match_release(self) -> None:
+        publication: dict = self.publication(matrix={'include': self.matrix(('1.20.1',))})
+        directory: Path = self.artifact_tree(publication)
+        for folder in directory.iterdir():
+            with self.subTest(target=folder.name):
+                path: Path = next(folder.iterdir())
+                original: bytes = path.read_bytes()
+                with zipfile.ZipFile(path) as archive:
+                    descriptor: str = archive.namelist()[0]
+                    contents: str = archive.read(descriptor).decode().replace('1.2.3', '1.2.4')
+                with zipfile.ZipFile(path, 'w') as archive:
+                    archive.writestr(descriptor, contents)
+                with self.assertRaises(ValueError):
+                    release.collect_artifacts(directory, publication)
+                path.write_bytes(original)
+
+    def test_modded_filename_must_match_minecraft_target(self) -> None:
+        publication: dict = self.publication(matrix={'include': self.matrix(('1.20.1',))})
+        directory: Path = self.artifact_tree(publication)
+        path: Path = next((directory / 'release-fabric-1.20.1').iterdir())
+        path.rename(path.with_name(path.name.replace('1.20.1', '1.21.1')))
+        with self.assertRaises(ValueError):
+            release.collect_artifacts(directory, publication)
+
+    def test_modded_metadata_must_match_minecraft_target(self) -> None:
+        publication: dict = self.publication(matrix={'include': self.matrix(('1.20.1',))})
+        directory: Path = self.artifact_tree(publication)
+        for folder in directory.iterdir():
+            with self.subTest(target=folder.name):
+                path: Path = next(folder.iterdir())
+                original: bytes = path.read_bytes()
+                with zipfile.ZipFile(path) as archive:
+                    descriptor: str = archive.namelist()[0]
+                    contents: str = archive.read(descriptor).decode().replace('1.20.1', '1.21.1')
+                with zipfile.ZipFile(path, 'w') as archive:
+                    archive.writestr(descriptor, contents)
+                with self.assertRaises(ValueError):
+                    release.collect_artifacts(directory, publication)
+                path.write_bytes(original)
+
+
+class PublicationTests(ReleaseTestCase):
+    def setUp(self) -> None:
+        super().setUp()
+        self.github: FakeGitHub = FakeGitHub()
+        self.assets: dict[str, bytes] = {'Example-1.2.3-bukkit.jar': b'jar', 'SHA256SUMS-1.2.3.txt': b'checksums'}
+
+    def test_new_stable_release_is_published_at_head(self) -> None:
+        release.publish(self.github, self.config, self.publication(), self.assets)
+        record: dict = self.github.releases[1]
+        self.assertEqual(SHA, self.github.tags['v1.2.3'])
+        self.assertFalse(record['draft'])
+        self.assertFalse(record['prerelease'])
+        self.assertEqual('true', record['make_latest'])
+        self.assertEqual(set(self.assets), set(self.github.uploads[1]))
+
+    def test_stable_existing_tag_collision_has_no_writes(self) -> None:
+        self.github.tags['v1.2.3'] = OTHER_SHA
+        with self.assertRaises(ValueError):
+            release.publish(self.github, self.config, self.publication(), self.assets)
+        self.assertEqual([], self.github.writes)
+        self.assertEqual(OTHER_SHA, self.github.tags['v1.2.3'])
+
+    def test_stable_same_content_rerun_has_no_writes(self) -> None:
+        self.github.seed(self.publication(), self.assets, immutable=True)
+        result: str = release.publish(self.github, self.config, self.publication(), self.assets)
+        self.assertIn('already published', result)
+        self.assertEqual([], self.github.writes)
+
+    def test_published_stable_artifacts_cannot_be_replaced(self) -> None:
+        self.github.seed(self.publication(), self.assets, immutable=True)
+        with self.assertRaises(ValueError):
+            release.publish(self.github, self.config, self.publication(),
+                            {**self.assets, 'Example-1.2.3-bukkit.jar': b'different'})
+        self.assertEqual([], self.github.writes)
+
+    def test_stable_release_identity_collision_has_no_writes(self) -> None:
+        self.github.seed(self.publication(sha=OTHER_SHA), self.assets)
+        self.github.tags['v1.2.3'] = SHA
+        with self.assertRaises(ValueError):
+            release.publish(self.github, self.config, self.publication(), self.assets)
+        self.assertEqual([], self.github.writes)
+
+    def test_stable_release_cannot_reuse_published_prerelease(self) -> None:
+        record: dict = self.github.seed(self.publication(), self.assets)
+        record['prerelease'] = True
+        with self.assertRaises(ValueError):
+            release.publish(self.github, self.config, self.publication(), self.assets)
+        self.assertEqual([], self.github.writes)
+
+    def test_partially_uploaded_stable_draft_resumes(self) -> None:
+        record: dict = self.github.seed(self.publication(), {'Example-1.2.3-bukkit.jar': b'jar'}, draft=True)
+        original_id: int = self.github.uploads[record['id']]['Example-1.2.3-bukkit.jar']['id']
+        release.publish(self.github, self.config, self.publication(), self.assets)
+        self.assertFalse(self.github.releases[record['id']]['draft'])
+        self.assertEqual(original_id, self.github.uploads[record['id']]['Example-1.2.3-bukkit.jar']['id'])
+        self.assertEqual(set(self.assets), set(self.github.uploads[record['id']]))
+        self.assertEqual(1, len(self.github.releases))
+
+    def test_conflicting_draft_asset_fails_without_replacement(self) -> None:
+        self.github.seed(self.publication(), {'Example-1.2.3-bukkit.jar': b'other'}, draft=True)
+        with self.assertRaises(ValueError):
+            release.publish(self.github, self.config, self.publication(), self.assets)
+        self.assertEqual([], self.github.writes)
+        self.assertTrue(self.github.releases[1]['draft'])
+
+    def test_newer_beta_run_or_attempt_is_preserved(self) -> None:
+        for run, attempt in ((18, 1), (17, 3)):
+            with self.subTest(run=run, attempt=attempt):
+                github: FakeGitHub = FakeGitHub()
+                github.seed(self.publication('beta', run=run, attempt=attempt, sha=OTHER_SHA), self.assets)
+                result: str = release.publish(github, self.config, self.publication('beta'), self.assets)
+                self.assertIn('Skipped', result)
+                self.assertEqual([], github.writes)
+                self.assertEqual(OTHER_SHA, github.tags['bukkit-beta'])
+
+    def test_successful_beta_replaces_assets_and_remains_prerelease(self) -> None:
+        previous: dict = self.publication('beta', run=16, attempt=1, sha=OTHER_SHA, version='1.2.3-beta.16.1')
+        record: dict = self.github.seed(previous, {'old.jar': b'old'})
+        release.publish(self.github, self.config, self.publication('beta'), self.assets)
+        current: dict = self.github.releases[record['id']]
+        self.assertEqual(SHA, self.github.tags['bukkit-beta'])
+        self.assertTrue(current['prerelease'])
+        self.assertFalse(current['draft'])
+        self.assertEqual('false', current['make_latest'])
+        self.assertEqual(set(self.assets), set(self.github.uploads[record['id']]))
+
+    def test_failed_beta_upload_preserves_tag_and_assets_in_recoverable_draft(self) -> None:
+        previous: dict = self.publication('beta', run=16, attempt=1, sha=OTHER_SHA, version='1.2.3-beta.16.1')
+        record: dict = self.github.seed(previous, {'old.jar': b'old'})
+        self.github.fail_upload = 'SHA256SUMS-1.2.3.txt'
+        with self.assertRaises(RuntimeError):
+            release.publish(self.github, self.config, self.publication('beta'), self.assets)
+        self.assertEqual(OTHER_SHA, self.github.tags['bukkit-beta'])
+        self.assertTrue(self.github.releases[record['id']]['draft'])
+        self.assertEqual(17, release.release_metadata(self.github.releases[record['id']])['run'])
+        self.assertIn('old.jar', self.github.uploads[record['id']])
+        self.assertFalse(any(method == 'DELETE' or path.startswith('git/refs')
+                             for method, path in self.github.writes))
+
+    def test_failed_beta_cleanup_resumes_without_reuploading_verified_assets(self) -> None:
+        previous: dict = self.publication('beta', run=16, attempt=1, sha=OTHER_SHA, version='1.2.3-beta.16.1')
+        record: dict = self.github.seed(previous, {'old.jar': b'old'})
+        self.github.fail_delete = self.github.uploads[record['id']]['old.jar']['id']
+        with self.assertRaises(RuntimeError):
+            release.publish(self.github, self.config, self.publication('beta'), self.assets)
+        self.assertTrue(self.github.releases[record['id']]['draft'])
+        self.assertEqual(OTHER_SHA, self.github.tags['bukkit-beta'])
+        uploaded_ids: dict[str, int] = {name: self.github.uploads[record['id']][name]['id'] for name in self.assets}
+        self.github.fail_delete = None
+        release.publish(self.github, self.config, self.publication('beta'), self.assets)
+        self.assertFalse(self.github.releases[record['id']]['draft'])
+        self.assertEqual(SHA, self.github.tags['bukkit-beta'])
+        self.assertEqual(uploaded_ids, {name: entry['id'] for name, entry in self.github.uploads[record['id']].items()})
+
+    def test_incomplete_newer_beta_draft_blocks_older_run(self) -> None:
+        self.github.seed(self.publication('beta', run=18, sha=OTHER_SHA), {}, draft=True)
+        result: str = release.publish(self.github, self.config, self.publication('beta'), self.assets)
+        self.assertIn('Skipped', result)
+        self.assertEqual([], self.github.writes)
+        self.assertTrue(self.github.releases[1]['draft'])
+
+    def test_starter_upload_in_draft_is_replaced_before_publication(self) -> None:
+        self.github.seed(self.publication(), {'Example-1.2.3-bukkit.jar': b''}, draft=True)
+        starter: dict = self.github.uploads[1]['Example-1.2.3-bukkit.jar']
+        identifier: int = starter['id']
+        starter.update({'state': 'starter', 'digest': None})
+        release.publish(self.github, self.config, self.publication(), self.assets)
+        self.assertFalse(self.github.releases[1]['draft'])
+        self.assertNotEqual(identifier, self.github.uploads[1]['Example-1.2.3-bukkit.jar']['id'])
+        self.assertEqual(digest(b'jar'), self.github.uploads[1]['Example-1.2.3-bukkit.jar']['digest'])
+
+    def test_invalid_upload_digest_does_not_create_tag_or_publish(self) -> None:
+        self.github.invalid_receipt = True
+        with self.assertRaises(ValueError):
+            release.publish(self.github, self.config, self.publication(), self.assets)
+        self.assertEqual({}, self.github.tags)
+        self.assertTrue(self.github.releases[1]['draft'])
+
+    def test_beta_will_not_replace_stable_or_immutable_release(self) -> None:
+        for immutable, prerelease in ((True, True), (False, False)):
+            with self.subTest(immutable=immutable, prerelease=prerelease):
+                github: FakeGitHub = FakeGitHub()
+                record: dict = github.seed(self.publication('beta', run=16, sha=OTHER_SHA), self.assets,
+                                           immutable=immutable)
+                record['prerelease'] = prerelease
+                with self.assertRaises(ValueError):
+                    release.publish(github, self.config, self.publication('beta'), self.assets)
+                self.assertEqual([], github.writes)
+
+    def test_unowned_existing_release_is_preserved(self) -> None:
+        record: dict = self.github.seed(self.publication(), self.assets)
+        record['body'] = 'Published manually'
+        with self.assertRaises(ValueError):
+            release.publish(self.github, self.config, self.publication(), self.assets)
+        self.assertEqual([], self.github.writes)
+
+    def test_beta_tag_without_release_is_preserved(self) -> None:
+        self.github.tags['bukkit-beta'] = OTHER_SHA
+        with self.assertRaises(ValueError):
+            release.publish(self.github, self.config, self.publication('beta'), self.assets)
+        self.assertEqual([], self.github.writes)
+
+    def test_modded_stable_release_never_changes_latest(self) -> None:
+        self.github.latest = {'tag_name': 'v1.0.0'}
+        release.publish(self.github, {**self.config, 'platform': 'modded'}, self.publication(), self.assets)
+        self.assertFalse(self.github.releases[1]['prerelease'])
+        self.assertEqual('false', self.github.releases[1]['make_latest'])
+        self.assertEqual('v1.0.0', self.github.latest['tag_name'])
+
+    def test_bukkit_backport_does_not_replace_newer_latest(self) -> None:
+        for latest in ('v1.3.0', 'v2.0.0', 'v1.2.3'):
+            with self.subTest(latest=latest):
+                github: FakeGitHub = FakeGitHub()
+                github.latest = {'tag_name': latest}
+                release.publish(github, self.config, self.publication(), self.assets)
+                self.assertEqual('false', github.releases[1]['make_latest'])
+                self.assertEqual(latest, github.latest['tag_name'])
+
+    def test_newer_bukkit_release_becomes_latest(self) -> None:
+        self.github.latest = {'tag_name': 'v1.2.2'}
+        release.publish(self.github, self.config, self.publication(), self.assets)
+        self.assertEqual('true', self.github.releases[1]['make_latest'])
+        self.assertEqual('v1.2.3', self.github.latest['tag_name'])
+
+
+class GitHubReadTests(ReleaseTestCase):
+    def test_annotated_tag_resolves_to_commit(self) -> None:
+        github: release.GitHub = release.GitHub('example/product', 'test-token')
+        responses: dict[str, dict] = {
+            'git/ref/tags/v1.2.3': {'object': {'type': 'tag', 'sha': OTHER_SHA}},
+            f'git/tags/{OTHER_SHA}': {'object': {'type': 'commit', 'sha': SHA}},
+        }
+        with patch.object(github, 'request', side_effect=lambda method, path, **options: responses[path]):
+            self.assertEqual(SHA, github.tag_commit('v1.2.3'))
+
+    def test_noncommit_tag_cannot_be_published(self) -> None:
+        github: release.GitHub = release.GitHub('example/product', 'test-token')
+        with patch.object(github, 'request', return_value={'object': {'type': 'tree', 'sha': SHA}}):
+            with self.assertRaises(ValueError):
+                github.tag_commit('v1.2.3')
+
+    def test_assets_include_all_pages(self) -> None:
+        github: release.GitHub = release.GitHub('example/product', 'test-token')
+        first: list[dict] = [{'id': number, 'name': f'{number}.jar'} for number in range(100)]
+        last: list[dict] = [{'id': 100, 'name': 'last.jar'}]
+        with patch.object(github, 'request', side_effect=[first, last]):
+            self.assertEqual(first + last, github.assets(1))
+
+    def test_invalid_repository_is_rejected(self) -> None:
+        for repository in ('example', '../example/product', 'example/product/extra'):
+            with self.subTest(repository=repository), self.assertRaises(ValueError):
+                release.GitHub(repository, 'test-token')
+
+
+class DependencyResolutionTests(ReleaseTestCase):
+    def test_branch_resolves_to_full_commit_sha(self) -> None:
+        with patch.object(release.GitHub, 'request', return_value={'sha': SHA}) as request:
+            self.assertEqual(SHA, release.resolve_dependency('example/product', 'master', 'test-token'))
+        request.assert_called_once_with('GET', 'commits/master')
+
+    def test_full_commit_reference_is_verified(self) -> None:
+        with patch.object(release.GitHub, 'request', return_value={'sha': SHA}) as request:
+            self.assertEqual(SHA, release.resolve_dependency('example/product', SHA, 'test-token'))
+        request.assert_called_once_with('GET', f'commits/{SHA}')
+
+    def test_incomplete_or_invalid_resolved_sha_fails(self) -> None:
+        for sha in ('', 'a' * 39, 'a' * 41, 'A' * 40, 'g' * 40, 'master'):
+            with self.subTest(sha=sha), patch.object(release.GitHub, 'request', return_value={'sha': sha}):
+                with self.assertRaises(ValueError):
+                    release.resolve_dependency('example/product', 'master', 'test-token')
+
+    def test_reference_is_encoded_as_single_url_path_component(self) -> None:
+        with patch.object(release.GitHub, 'request', return_value={'sha': SHA}) as request:
+            self.assertEqual(SHA, release.resolve_dependency('example/product', 'feature/next+release #?', 'test-token'))
+        request.assert_called_once_with('GET', 'commits/feature%2Fnext%2Brelease%20%23%3F')
+
+
+class MainTests(ReleaseTestCase):
+    def setUp(self) -> None:
+        super().setUp()
+        self.config.update({'volmlibRef': 'master', 'wormholesRef': 'release/api'})
+        (self.root / '.github').mkdir()
+        (self.root / '.github/release.json').write_text(json.dumps(self.config))
+        self.event['head_commit']['message'] = 'B+ Publish beta'
+        (self.root / 'event.json').write_text(json.dumps(self.event))
+        self.environment.update({
+            'GITHUB_EVENT_PATH': str(self.root / 'event.json'),
+            'GITHUB_OUTPUT': str(self.root / 'output.txt'),
+            'GITHUB_REPOSITORY': 'example/product',
+            'GH_TOKEN': 'test-token',
+        })
+        script = patch.object(release, '__file__', str(self.root / '.github/release.py'))
+        script.start()
+        self.addCleanup(script.stop)
+        output = patch('sys.stdout', new=io.StringIO())
+        output.start()
+        self.addCleanup(output.stop)
+
+    def test_plan_freezes_each_dependency_branch_once(self) -> None:
+        with patch.dict(release.os.environ, self.environment, clear=True), \
+                patch.object(release.sys, 'argv', ['release.py', 'plan']), \
+                patch.object(release.GitHub, 'request', side_effect=[{'sha': SHA}, {'sha': OTHER_SHA}]) as request:
+            release.main()
+        outputs: dict[str, str] = dict(line.split('=', 1) for line in (self.root / 'output.txt').read_text().splitlines())
+        self.assertEqual(SHA, outputs['volmlib_ref'])
+        self.assertEqual(OTHER_SHA, outputs['wormholes_ref'])
+        self.assertEqual('1.2.3-beta.17.2', outputs['version'])
+        self.assertEqual('2', outputs['attempt'])
+        self.assertEqual(2, request.call_count)
+        self.assertEqual(['commits/master', 'commits/release%2Fapi'], [call.args[1] for call in request.call_args_list])
+
+    def test_unmarked_push_never_resolves_dependencies(self) -> None:
+        self.event['head_commit']['message'] = 'Fix a bug'
+        (self.root / 'event.json').write_text(json.dumps(self.event))
+        with patch.dict(release.os.environ, self.environment, clear=True), \
+                patch.object(release.sys, 'argv', ['release.py', 'plan']), \
+                patch.object(release, 'resolve_dependency', side_effect=AssertionError('Unexpected dependency lookup')):
+            release.main()
+        self.assertEqual('channel=none\n', (self.root / 'output.txt').read_text())
+
+    def test_publish_rerun_uses_original_planned_attempt_and_dependency_commits(self) -> None:
+        publication: dict = self.publication('beta')
+        artifacts: Path = self.artifact_tree(publication)
+        github: FakeGitHub = FakeGitHub()
+        self.environment.update({'GITHUB_RUN_ATTEMPT': '3', 'RELEASE_ATTEMPT': '2',
+                                  'RELEASE_VOLMLIB_REF': SHA, 'RELEASE_WORMHOLES_REF': OTHER_SHA})
+        with patch.dict(release.os.environ, self.environment, clear=True), \
+                patch.object(release.sys, 'argv', ['release.py', 'publish', '--artifacts', str(artifacts)]), \
+                patch.object(release, 'GitHub', return_value=github), \
+                patch.object(release, 'resolve_dependency', side_effect=AssertionError('Dependencies must stay frozen')):
+            release.main()
+            metadata: dict = release.release_metadata(github.releases[1])
+            self.assertEqual('1.2.3-beta.17.2', metadata['version'])
+            self.assertEqual(2, metadata['attempt'])
+            self.assertEqual(SHA, metadata['volmlib_ref'])
+            self.assertEqual(OTHER_SHA, metadata['wormholes_ref'])
+            self.assertFalse(github.releases[1]['draft'])
+            self.assertEqual({'Example-1.2.3-beta.17.2-bukkit.jar', 'SHA256SUMS-1.2.3-beta.17.2.txt'},
+                             set(github.uploads[1]))
+            writes: list[tuple[str, str]] = github.writes.copy()
+            release.os.environ['GITHUB_RUN_ATTEMPT'] = '4'
+            release.main()
+            self.assertEqual(writes, github.writes)
+
+    def test_publish_rejects_unresolved_dependency_reference_before_writing(self) -> None:
+        artifacts: Path = self.artifact_tree(self.publication('beta'))
+        github: FakeGitHub = FakeGitHub()
+        self.environment.update({'RELEASE_ATTEMPT': '2', 'RELEASE_VOLMLIB_REF': SHA,
+                                  'RELEASE_WORMHOLES_REF': OTHER_SHA})
+        for key in ('RELEASE_VOLMLIB_REF', 'RELEASE_WORMHOLES_REF'):
+            with self.subTest(key=key), \
+                    patch.dict(release.os.environ, {**self.environment, key: 'master'}, clear=True), \
+                    patch.object(release.sys, 'argv', ['release.py', 'publish', '--artifacts', str(artifacts)]), \
+                    patch.object(release, 'GitHub', return_value=github):
+                with self.assertRaises(ValueError):
+                    release.main()
+                self.assertEqual([], github.writes)
+
+
+if __name__ == '__main__':
+    unittest.main()
@@ -0,0 +1,157 @@
+name: Release
+
+on:
+  push:
+    branches: ['**']
+  pull_request:
+    paths:
+      - '.github/**'
+      - '**/*.gradle'
+      - '**/gradle.properties'
+      - 'gradle/**/*.json'
+
+permissions:
+  contents: read
+
+env:
+  PYTHONDONTWRITEBYTECODE: '1'
+
+jobs:
+  validate:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1
+        with:
+          persist-credentials: false
+      - name: Test release handling
+        run: python3 -m unittest discover -s .github -p 'test_release.py' -v
+
+  plan:
+    needs: validate
+    if: github.event_name == 'push' && github.ref == format('refs/heads/{0}', github.event.repository.default_branch)
+    runs-on: ubuntu-latest
+    outputs:
+      channel: ${{ steps.release.outputs.channel }}
+      version: ${{ steps.release.outputs.version }}
+      attempt: ${{ steps.release.outputs.attempt }}
+      version_property: ${{ steps.release.outputs.version_property }}
+      matrix: ${{ steps.release.outputs.matrix }}
+      volmlib_ref: ${{ steps.release.outputs.volmlib_ref }}
+      wormholes_ref: ${{ steps.release.outputs.wormholes_ref }}
+    steps:
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1
+        with:
+          persist-credentials: false
+      - name: Select release channel and targets
+        id: release
+        env:
+          GH_TOKEN: ${{ github.token }}
+        run: python3 .github/release.py plan
+
+  build:
+    needs: plan
+    if: needs.plan.outputs.channel != 'none'
+    runs-on: ubuntu-latest
+    timeout-minutes: 120
+    strategy:
+      fail-fast: false
+      max-parallel: 3
+      matrix: ${{ fromJSON(needs.plan.outputs.matrix) }}
+    env:
+      ORG_GRADLE_PROJECT_localVolmLibDirectory: ${{ github.workspace }}/VolmLib
+      RELEASE_VERSION: ${{ needs.plan.outputs.version }}
+      VERSION_PROPERTY: ${{ needs.plan.outputs.version_property }}
+      RELEASE_LOADER: ${{ matrix.loader }}
+      MINECRAFT_VERSION: ${{ matrix.minecraft }}
+    steps:
+      - name: Check out release sources
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1
+        with:
+          path: project
+          submodules: recursive
+          persist-credentials: false
+      - name: Check out VolmLib
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1
+        with:
+          repository: VolmitSoftware/VolmLib
+          ref: ${{ needs.plan.outputs.volmlib_ref }}
+          path: VolmLib
+          persist-credentials: false
+      - name: Check out Wormholes API sources
+        if: needs.plan.outputs.wormholes_ref != ''
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1
+        with:
+          repository: VolmitSoftware/Wormholes
+          ref: ${{ needs.plan.outputs.wormholes_ref }}
+          path: WormholesPlugin
+          submodules: recursive
+          persist-credentials: false
+      - name: Set up Java 21 toolchain
+        uses: actions/setup-java@b843ebf9b913146b38da2eaa7aeddf76074ae1ad
+        with:
+          distribution: temurin
+          java-version: '21'
+      - name: Set up Java 25
+        uses: actions/setup-java@b843ebf9b913146b38da2eaa7aeddf76074ae1ad
+        with:
+          distribution: temurin
+          java-version: '25'
+      - uses: gradle/actions/setup-gradle@3f5f9adaf7d9fecd50b5935e54106014257a94e6
+      - name: Build Wormholes API
+        if: needs.plan.outputs.wormholes_ref != ''
+        working-directory: WormholesPlugin
+        run: ./gradlew apiJar --no-daemon --max-workers=2 '-Dorg.gradle.jvmargs=-Xmx2g -Dfile.encoding=UTF-8'
+      - name: Locate Wormholes API
+        if: needs.plan.outputs.wormholes_ref != ''
+        shell: bash
+        run: |
+          api_jars=(WormholesPlugin/build/libs/*-api.jar)
+          test "${#api_jars[@]}" -eq 1
+          test -f "${api_jars[0]}"
+          echo "ORG_GRADLE_PROJECT_wormholesApiJar=$PWD/${api_jars[0]}" >> "$GITHUB_ENV"
+      - name: Build and verify release jar
+        working-directory: project
+        shell: bash
+        run: |
+          arguments=(prepareRelease --no-daemon --max-workers=2
+            '-Dorg.gradle.jvmargs=-Xmx2g -Dfile.encoding=UTF-8'
+            "-P$VERSION_PROPERTY=$RELEASE_VERSION")
+          if [[ "$RELEASE_LOADER" != bukkit ]]; then
+            arguments+=("-PreleaseLoader=$RELEASE_LOADER" "-PminecraftVersion=$MINECRAFT_VERSION"
+              -PmoddedBuildParallelism=1 -PmoddedTestForks=1)
+          fi
+          ./gradlew "${arguments[@]}"
+      - name: Upload verified jar
+        uses: actions/upload-artifact@cf430e030ddbb5b0abf93d22962f4752f3646cd9
+        with:
+          name: release-${{ matrix.id }}
+          path: project/build/release/*.jar
+          if-no-files-found: error
+          retention-days: 7
+          compression-level: 0
+
+  publish:
+    needs: [plan, build]
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write
+    concurrency:
+      group: release-publication
+      cancel-in-progress: false
+      queue: max
+    steps:
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1
+        with:
+          persist-credentials: false
+      - name: Download complete release matrix
+        uses: actions/download-artifact@9000827ccba6bdab643e8b6fd33ac0654aef8333
+        with:
+          pattern: release-*
+          path: build/release-artifacts
+      - name: Publish verified release
+        env:
+          GH_TOKEN: ${{ github.token }}
+          RELEASE_ATTEMPT: ${{ needs.plan.outputs.attempt }}
+          RELEASE_VOLMLIB_REF: ${{ needs.plan.outputs.volmlib_ref }}
+          RELEASE_WORMHOLES_REF: ${{ needs.plan.outputs.wormholes_ref }}
+        run: python3 .github/release.py publish --artifacts build/release-artifacts
@@ -76,3 +76,10 @@ BUILDS/
 .compatwt/

 .worktrees/
+
+/VolmLib/
+/docs/
+/.perf/
+/.codegraph/
+
+.superpowers/
@@ -1,160 +1,215 @@
                    GNU GENERAL PUBLIC LICENSE
                       Version 3, 29 June 2007

-Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
-Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.
+ Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.

                            Preamble

-The GNU General Public License is a free, copyleft license for software and other kinds of works.
+  The GNU General Public License is a free, copyleft license for
+software and other kinds of works.

-The licenses for most software and other practical works are designed to take away your freedom to share and change the
-works. By contrast, the GNU General Public License is intended to guarantee your freedom to share and change all
-versions of a program--to make sure it remains free software for all its users. We, the Free Software Foundation, use
-the GNU General Public License for most of our software; it applies also to any other work released this way by its
-authors. You can apply it to your programs, too.
+  The licenses for most software and other practical works are designed
+to take away your freedom to share and change the works.  By contrast,
+the GNU General Public License is intended to guarantee your freedom to
+share and change all versions of a program--to make sure it remains free
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+GNU General Public License for most of our software; it applies also to
+any other work released this way by its authors.  You can apply it to
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-Developers that use the GNU GPL protect your rights with two steps:
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+makes it unnecessary.

-3. Protecting Users' Legal Rights From Anti-Circumvention Law.
+  3. Protecting Users' Legal Rights From Anti-Circumvention Law.

-No covered work shall be deemed part of an effective technological measure under any applicable law fulfilling
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-restricting circumvention of such measures.
+  No covered work shall be deemed part of an effective technological
+measure under any applicable law fulfilling obligations under article
+11 of the WIPO copyright treaty adopted on 20 December 1996, or
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-When you convey a covered work, you waive any legal power to forbid circumvention of technological measures to the
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+users, your or third parties' legal rights to forbid circumvention of
+technological measures.

-4. Conveying Verbatim Copies.
+  4. Conveying Verbatim Copies.

-You may convey verbatim copies of the Program's source code as you receive it, in any medium, provided that you
-conspicuously and appropriately publish on each copy an appropriate copyright notice; keep intact all notices stating
-that this License and any non-permissive terms added in accord with section 7 apply to the code; keep intact all notices
-of the absence of any warranty; and give all recipients a copy of this License along with the Program.
+  You may convey verbatim copies of the Program's source code as you
+receive it, in any medium, provided that you conspicuously and
+appropriately publish on each copy an appropriate copyright notice;
+keep intact all notices stating that this License and any
+non-permissive terms added in accord with section 7 apply to the code;
+keep intact all notices of the absence of any warranty; and give all
+recipients a copy of this License along with the Program.

-You may charge any price or no price for each copy that you convey, and you may offer support or warranty protection for
-a fee.
+  You may charge any price or no price for each copy that you convey,
+and you may offer support or warranty protection for a fee.

-5. Conveying Modified Source Versions.
+  5. Conveying Modified Source Versions.

-You may convey a work based on the Program, or the modifications to produce it from the Program, in the form of source
-code under the terms of section 4, provided that you also meet all of these conditions:
+  You may convey a work based on the Program, or the modifications to
+produce it from the Program, in the form of source code under the
+terms of section 4, provided that you also meet all of these conditions:

    a) The work must carry prominent notices stating that you modified
    it, and giving a relevant date.
@@ -177,17 +232,22 @@ code under the terms of section 4, provided that you also meet all of these cond
    interfaces that do not display Appropriate Legal Notices, your
    work need not make them do so.

-A compilation of a covered work with other separate and independent works, which are not by their nature extensions of
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-"aggregate" if the compilation and its resulting copyright are not used to limit the access or legal rights of the
-compilation's users beyond what the individual works permit. Inclusion of a covered work in an aggregate does not cause
-this License to apply to the other parts of the aggregate.
+  A compilation of a covered work with other separate and independent
+works, which are not by their nature extensions of the covered work,
+and which are not combined with it such as to form a larger program,
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+used to limit the access or legal rights of the compilation's users
+beyond what the individual works permit.  Inclusion of a covered work
+in an aggregate does not cause this License to apply to the other
+parts of the aggregate.

-6. Conveying Non-Source Forms.
+  6. Conveying Non-Source Forms.

-You may convey a covered work in object code form under the terms of sections 4 and 5, provided that you also convey the
-machine-readable Corresponding Source under the terms of this License, in one of these ways:
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+machine-readable Corresponding Source under the terms of this License,
+in one of these ways:

    a) Convey the object code in, or embodied in, a physical product
    (including a physical distribution medium), accompanied by the
@@ -230,55 +290,77 @@ machine-readable Corresponding Source under the terms of this License, in one of
    Source of the work are being offered to the general public at no
    charge under subsection 6d.

-A separable portion of the object code, whose source code is excluded from the Corresponding Source as a System Library,
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-7. Additional Terms.
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-"Additional permissions" are terms that supplement the terms of this License by making exceptions from one or more of
-its conditions. Additional permissions that are applicable to the entire Program shall be treated as though they were
-included in this License, to the extent that they are valid under applicable law. If additional permissions apply only
-to part of the Program, that part may be used separately under those permissions, but the entire Program remains
-governed by this License without regard to the additional permissions.
+  "Additional permissions" are terms that supplement the terms of this
+License by making exceptions from one or more of its conditions.
+Additional permissions that are applicable to the entire Program shall
+be treated as though they were included in this License, to the extent
+that they are valid under applicable law.  If additional permissions
+apply only to part of the Program, that part may be used separately
+under those permissions, but the entire Program remains governed by
+this License without regard to the additional permissions.

-When you convey a copy of a covered work, you may at your option remove any additional permissions from that copy, or
-from any part of it.  (Additional permissions may be written to require their own removal in certain cases when you
-modify the work.)  You may place additional permissions on material, added by you to a covered work, for which you have
-or can give appropriate copyright permission.
+  When you convey a copy of a covered work, you may at your option
+remove any additional permissions from that copy, or from any part of
+it.  (Additional permissions may be written to require their own
+removal in certain cases when you modify the work.)  You may place
+additional permissions on material, added by you to a covered work,
+for which you have or can give appropriate copyright permission.

-Notwithstanding any other provision of this License, for material you add to a covered work, you may (if authorized by
-the copyright holders of that material) supplement the terms of this License with terms:
+  Notwithstanding any other provision of this License, for material you
+add to a covered work, you may (if authorized by the copyright holders of
+that material) supplement the terms of this License with terms:

    a) Disclaiming warranty or limiting liability differently from the
    terms of sections 15 and 16 of this License; or
@@ -303,182 +385,251 @@ the copyright holders of that material) supplement the terms of this License wit
    any liability that these contractual assumptions directly impose on
    those licensors and authors.

-All other non-permissive additional terms are considered "further restrictions" within the meaning of section 10. If the
-Program as you received it, or any part of it, contains a notice stating that it is governed by this License along with
-a term that is a further restriction, you may remove that term. If a license document contains a further restriction but
-permits relicensing or conveying under this License, you may add to a covered work material governed by the terms of
-that license document, provided that the further restriction does not survive such relicensing or conveying.
+  All other non-permissive additional terms are considered "further
+restrictions" within the meaning of section 10.  If the Program as you
+received it, or any part of it, contains a notice stating that it is
+governed by this License along with a term that is a further
+restriction, you may remove that term.  If a license document contains
+a further restriction but permits relicensing or conveying under this
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+not survive such relicensing or conveying.

-If you add terms to a covered work in accord with this section, you must place, in the relevant source files, a
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-Additional terms, permissive or non-permissive, may be stated in the form of a separately written license, or stated as
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+  Additional terms, permissive or non-permissive, may be stated in the
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-8. Termination.
+  8. Termination.

-You may not propagate or modify a covered work except as expressly provided under this License. Any attempt otherwise to
-propagate or modify it is void, and will automatically terminate your rights under this License (including any patent
-licenses granted under the third paragraph of section 11).
+  You may not propagate or modify a covered work except as expressly
+provided under this License.  Any attempt otherwise to propagate or
+modify it is void, and will automatically terminate your rights under
+this License (including any patent licenses granted under the third
+paragraph of section 11).

-However, if you cease all violation of this License, then your license from a particular copyright holder is
-reinstated (a)
-provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b)
-permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days
-after the cessation.
+  However, if you cease all violation of this License, then your
+license from a particular copyright holder is reinstated (a)
+provisionally, unless and until the copyright holder explicitly and
+finally terminates your license, and (b) permanently, if the copyright
+holder fails to notify you of the violation by some reasonable means
+prior to 60 days after the cessation.

-Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you
-of the violation by some reasonable means, this is the first time you have received notice of violation of this
-License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the
-notice.
+  Moreover, your license from a particular copyright holder is
+reinstated permanently if the copyright holder notifies you of the
+violation by some reasonable means, this is the first time you have
+received notice of violation of this License (for any work) from that
+copyright holder, and you cure the violation prior to 30 days after
+your receipt of the notice.

-Termination of your rights under this section does not terminate the licenses of parties who have received copies or
-rights from you under this License. If your rights have been terminated and not permanently reinstated, you do not
-qualify to receive new licenses for the same material under section 10.
+  Termination of your rights under this section does not terminate the
+licenses of parties who have received copies or rights from you under
+this License.  If your rights have been terminated and not permanently
+reinstated, you do not qualify to receive new licenses for the same
+material under section 10.

-9. Acceptance Not Required for Having Copies.
+  9. Acceptance Not Required for Having Copies.

-You are not required to accept this License in order to receive or run a copy of the Program. Ancillary propagation of a
-covered work occurring solely as a consequence of using peer-to-peer transmission to receive a copy likewise does not
-require acceptance. However, nothing other than this License grants you permission to propagate or modify any covered
-work. These actions infringe copyright if you do not accept this License. Therefore, by modifying or propagating a
+  You are not required to accept this License in order to receive or
+run a copy of the Program.  Ancillary propagation of a covered work
+occurring solely as a consequence of using peer-to-peer transmission
+to receive a copy likewise does not require acceptance.  However,
+nothing other than this License grants you permission to propagate or
+modify any covered work.  These actions infringe copyright if you do
+not accept this License.  Therefore, by modifying or propagating a
 covered work, you indicate your acceptance of this License to do so.

-10. Automatic Licensing of Downstream Recipients.
+  10. Automatic Licensing of Downstream Recipients.

-Each time you convey a covered work, the recipient automatically receives a license from the original licensors, to run,
-modify and propagate that work, subject to this License. You are not responsible for enforcing compliance by third
-parties with this License.
+  Each time you convey a covered work, the recipient automatically
+receives a license from the original licensors, to run, modify and
+propagate that work, subject to this License.  You are not responsible
+for enforcing compliance by third parties with this License.

-An "entity transaction" is a transaction transferring control of an organization, or substantially all assets of one, or
-subdividing an organization, or merging organizations. If propagation of a covered work results from an entity
-transaction, each party to that transaction who receives a copy of the work also receives whatever licenses to the work
-the party's predecessor in interest had or could give under the previous paragraph, plus a right to possession of the
-Corresponding Source of the work from the predecessor in interest, if the predecessor has it or can get it with
-reasonable efforts.
+  An "entity transaction" is a transaction transferring control of an
+organization, or substantially all assets of one, or subdividing an
+organization, or merging organizations.  If propagation of a covered
+work results from an entity transaction, each party to that
+transaction who receives a copy of the work also receives whatever
+licenses to the work the party's predecessor in interest had or could
+give under the previous paragraph, plus a right to possession of the
+Corresponding Source of the work from the predecessor in interest, if
+the predecessor has it or can get it with reasonable efforts.

-You may not impose any further restrictions on the exercise of the rights granted or affirmed under this License. For
-example, you may not impose a license fee, royalty, or other charge for exercise of rights granted under this License,
-and you may not initiate litigation
-(including a cross-claim or counterclaim in a lawsuit) alleging that any patent claim is infringed by making, using,
-selling, offering for sale, or importing the Program or any portion of it.
+  You may not impose any further restrictions on the exercise of the
+rights granted or affirmed under this License.  For example, you may
+not impose a license fee, royalty, or other charge for exercise of
+rights granted under this License, and you may not initiate litigation
+(including a cross-claim or counterclaim in a lawsuit) alleging that
+any patent claim is infringed by making, using, selling, offering for
+sale, or importing the Program or any portion of it.

-11. Patents.
+  11. Patents.

-A "contributor" is a copyright holder who authorizes use under this License of the Program or a work on which the
-Program is based. The work thus licensed is called the contributor's "contributor version".
+  A "contributor" is a copyright holder who authorizes use under this
+License of the Program or a work on which the Program is based.  The
+work thus licensed is called the contributor's "contributor version".

-A contributor's "essential patent claims" are all patent claims owned or controlled by the contributor, whether already
-acquired or hereafter acquired, that would be infringed by some manner, permitted by this License, of making, using, or
-selling its contributor version, but do not include claims that would be infringed only as a consequence of further
-modification of the contributor version. For purposes of this definition, "control" includes the right to grant patent
-sublicenses in a manner consistent with the requirements of this License.
+  A contributor's "essential patent claims" are all patent claims
+owned or controlled by the contributor, whether already acquired or
+hereafter acquired, that would be infringed by some manner, permitted
+by this License, of making, using, or selling its contributor version,
+but do not include claims that would be infringed only as a
+consequence of further modification of the contributor version.  For
+purposes of this definition, "control" includes the right to grant
+patent sublicenses in a manner consistent with the requirements of
+this License.

-Each contributor grants you a non-exclusive, worldwide, royalty-free patent license under the contributor's essential
-patent claims, to make, use, sell, offer for sale, import and otherwise run, modify and propagate the contents of its
-contributor version.
+  Each contributor grants you a non-exclusive, worldwide, royalty-free
+patent license under the contributor's essential patent claims, to
+make, use, sell, offer for sale, import and otherwise run, modify and
+propagate the contents of its contributor version.

-In the following three paragraphs, a "patent license" is any express agreement or commitment, however denominated, not
-to enforce a patent
-(such as an express permission to practice a patent or covenant not to sue for patent infringement). To "grant" such a
-patent license to a party means to make such an agreement or commitment not to enforce a patent against the party.
+  In the following three paragraphs, a "patent license" is any express
+agreement or commitment, however denominated, not to enforce a patent
+(such as an express permission to practice a patent or covenant not to
+sue for patent infringement).  To "grant" such a patent license to a
+party means to make such an agreement or commitment not to enforce a
+patent against the party.

-If you convey a covered work, knowingly relying on a patent license, and the Corresponding Source of the work is not
-available for anyone to copy, free of charge and under the terms of this License, through a publicly available network
-server or other readily accessible means, then you must either (1) cause the Corresponding Source to be so available,
-or (2) arrange to deprive yourself of the benefit of the patent license for this particular work, or (3) arrange, in a
-manner consistent with the requirements of this License, to extend the patent license to downstream recipients.  "
-Knowingly relying" means you have actual knowledge that, but for the patent license, your conveying the covered work in
-a country, or your recipient's use of the covered work in a country, would infringe one or more identifiable patents in
-that country that you have reason to believe are valid.
+  If you convey a covered work, knowingly relying on a patent license,
+and the Corresponding Source of the work is not available for anyone
+to copy, free of charge and under the terms of this License, through a
+publicly available network server or other readily accessible means,
+then you must either (1) cause the Corresponding Source to be so
+available, or (2) arrange to deprive yourself of the benefit of the
+patent license for this particular work, or (3) arrange, in a manner
+consistent with the requirements of this License, to extend the patent
+license to downstream recipients.  "Knowingly relying" means you have
+actual knowledge that, but for the patent license, your conveying the
+covered work in a country, or your recipient's use of the covered work
+in a country, would infringe one or more identifiable patents in that
+country that you have reason to believe are valid.

-If, pursuant to or in connection with a single transaction or arrangement, you convey, or propagate by procuring
-conveyance of, a covered work, and grant a patent license to some of the parties receiving the covered work authorizing
-them to use, propagate, modify or convey a specific copy of the covered work, then the patent license you grant is
-automatically extended to all recipients of the covered work and works based on it.
+  If, pursuant to or in connection with a single transaction or
+arrangement, you convey, or propagate by procuring conveyance of, a
+covered work, and grant a patent license to some of the parties
+receiving the covered work authorizing them to use, propagate, modify
+or convey a specific copy of the covered work, then the patent license
+you grant is automatically extended to all recipients of the covered
+work and works based on it.

-A patent license is "discriminatory" if it does not include within the scope of its coverage, prohibits the exercise of,
-or is conditioned on the non-exercise of one or more of the rights that are specifically granted under this License. You
-may not convey a covered work if you are a party to an arrangement with a third party that is in the business of
-distributing software, under which you make payment to the third party based on the extent of your activity of conveying
-the work, and under which the third party grants, to any of the parties who would receive the covered work from you, a
-discriminatory patent license (a) in connection with copies of the covered work conveyed by you (or copies made from
-those copies), or (b) primarily for and in connection with specific products or compilations that contain the covered
-work, unless you entered into that arrangement, or that patent license was granted, prior to 28 March 2007.
+  A patent license is "discriminatory" if it does not include within
+the scope of its coverage, prohibits the exercise of, or is
+conditioned on the non-exercise of one or more of the rights that are
+specifically granted under this License.  You may not convey a covered
+work if you are a party to an arrangement with a third party that is
+in the business of distributing software, under which you make payment
+to the third party based on the extent of your activity of conveying
+the work, and under which the third party grants, to any of the
+parties who would receive the covered work from you, a discriminatory
+patent license (a) in connection with copies of the covered work
+conveyed by you (or copies made from those copies), or (b) primarily
+for and in connection with specific products or compilations that
+contain the covered work, unless you entered into that arrangement,
+or that patent license was granted, prior to 28 March 2007.

-Nothing in this License shall be construed as excluding or limiting any implied license or other defenses to
-infringement that may otherwise be available to you under applicable patent law.
+  Nothing in this License shall be construed as excluding or limiting
+any implied license or other defenses to infringement that may
+otherwise be available to you under applicable patent law.

-12. No Surrender of Others' Freedom.
+  12. No Surrender of Others' Freedom.

-If conditions are imposed on you (whether by court order, agreement or otherwise) that contradict the conditions of this
-License, they do not excuse you from the conditions of this License. If you cannot convey a covered work so as to
-satisfy simultaneously your obligations under this License and any other pertinent obligations, then as a consequence
-you may not convey it at all. For example, if you agree to terms that obligate you to collect a royalty for further
-conveying from those to whom you convey the Program, the only way you could satisfy both those terms and this License
-would be to refrain entirely from conveying the Program.
+  If conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License.  If you cannot convey a
+covered work so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you may
+not convey it at all.  For example, if you agree to terms that obligate you
+to collect a royalty for further conveying from those to whom you convey
+the Program, the only way you could satisfy both those terms and this
+License would be to refrain entirely from conveying the Program.

-13. Use with the GNU Affero General Public License.
+  13. Use with the GNU Affero General Public License.

-Notwithstanding any other provision of this License, you have permission to link or combine any covered work with a work
-licensed under version 3 of the GNU Affero General Public License into a single combined work, and to convey the
-resulting work. The terms of this License will continue to apply to the part which is the covered work, but the special
-requirements of the GNU Affero General Public License, section 13, concerning interaction through a network will apply
-to the combination as such.
+  Notwithstanding any other provision of this License, you have
+permission to link or combine any covered work with a work licensed
+under version 3 of the GNU Affero General Public License into a single
+combined work, and to convey the resulting work.  The terms of this
+License will continue to apply to the part which is the covered work,
+but the special requirements of the GNU Affero General Public License,
+section 13, concerning interaction through a network will apply to the
+combination as such.

-14. Revised Versions of this License.
+  14. Revised Versions of this License.

-The Free Software Foundation may publish revised and/or new versions of the GNU General Public License from time to
-time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new
-problems or concerns.
+  The Free Software Foundation may publish revised and/or new versions of
+the GNU General Public License from time to time.  Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.

-Each version is given a distinguishing version number. If the Program specifies that a certain numbered version of the
-GNU General Public License "or any later version" applies to it, you have the option of following the terms and
-conditions either of that numbered version or of any later version published by the Free Software Foundation. If the
-Program does not specify a version number of the GNU General Public License, you may choose any version ever published
+  Each version is given a distinguishing version number.  If the
+Program specifies that a certain numbered version of the GNU General
+Public License "or any later version" applies to it, you have the
+option of following the terms and conditions either of that numbered
+version or of any later version published by the Free Software
+Foundation.  If the Program does not specify a version number of the
+GNU General Public License, you may choose any version ever published
 by the Free Software Foundation.

-If the Program specifies that a proxy can decide which future versions of the GNU General Public License can be used,
-that proxy's public statement of acceptance of a version permanently authorizes you to choose that version for the
-Program.
+  If the Program specifies that a proxy can decide which future
+versions of the GNU General Public License can be used, that proxy's
+public statement of acceptance of a version permanently authorizes you
+to choose that version for the Program.

-Later license versions may give you additional or different permissions. However, no additional obligations are imposed
-on any author or copyright holder as a result of your choosing to follow a later version.
+  Later license versions may give you additional or different
+permissions.  However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
+later version.

-15. Disclaimer of Warranty.
+  15. Disclaimer of Warranty.

-THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING
-THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR
-IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
-THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU
-ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.

-16. Limitation of Liability.
+  16. Limitation of Liability.

-IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO
-MODIFIES AND/OR CONVEYS THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL,
-INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO
-LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM
-TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
-DAMAGES.
+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.

-17. Interpretation of Sections 15 and 16.
+  17. Interpretation of Sections 15 and 16.

-If the disclaimer of warranty and limitation of liability provided above cannot be given local legal effect according to
-their terms, reviewing courts shall apply local law that most closely approximates an absolute waiver of all civil
-liability in connection with the Program, unless a warranty or assumption of liability accompanies a copy of the Program
-in return for a fee.
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.

                     END OF TERMS AND CONDITIONS

            How to Apply These Terms to Your New Programs

-If you develop a new program, and you want it to be of the greatest possible use to the public, the best way to achieve
-this is to make it free software which everyone can redistribute and change under these terms.
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.

-To do so, attach the following notices to the program. It is safest to attach them to the start of each source file to
-most effectively state the exclusion of warranty; and each file should have at least the "copyright" line and a pointer
-to where the full notice is found.
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.

    <one line to give the program's name and a brief idea of what it does.>
    Copyright (C) <year>  <name of author>
@@ -498,21 +649,26 @@ to where the full notice is found.

 Also add information on how to contact you by electronic and paper mail.

-If the program does terminal interaction, make it output a short notice like this when it starts in an interactive mode:
+  If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:

    <program>  Copyright (C) <year>  <name of author>
    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
    This is free software, and you are welcome to redistribute it
    under certain conditions; type `show c' for details.

-The hypothetical commands `show w' and `show c' should show the appropriate parts of the General Public License. Of
-course, your program's commands might be different; for a GUI interface, you would use an "about box".
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".

-You should also get your employer (if you work as a programmer) or school, if any, to sign a "copyright disclaimer" for
-the program, if necessary. For more information on this, and how to apply and follow the GNU GPL, see
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
 <https://www.gnu.org/licenses/>.

-The GNU General Public License does not permit incorporating your program into proprietary programs. If your program is
-a subroutine library, you may consider it more useful to permit linking proprietary applications with the library. If
-this is what you want to do, use the GNU Lesser General Public License instead of this License. But first, please read
+  The GNU General Public License does not permit incorporating your program
+into proprietary programs.  If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.  But first, please read
 <https://www.gnu.org/licenses/why-not-lgpl.html>.
@@ -25,7 +25,7 @@ Canonical English is defined in the typed Java catalogs under `core/src/main/jav
 | Spigot / CraftBukkit | plugin jar | 26.1.2 - 26.3 | Managed `iris:*` creation and generation; exact vanilla-slot `/iris replace` is unavailable |
 | Fabric | mod jar | 26.3 | Server worldgen + client HUD; requires Fabric Loader 0.19.5+ |
 | Forge | mod jar | 26.3 | Server worldgen + client HUD; current target is Forge 26.3-66.0.8 |
-| NeoForge | mod jar | 26.3 | Server worldgen + client HUD; current target is NeoForge 26.3.0.33-beta |
+| NeoForge | mod jar | 26.3 | Server worldgen + client HUD; requires NeoForge 26.3.0.65-beta+; current target is NeoForge 26.3.0.83 |

 Java 25 is required on every platform.

@@ -248,28 +248,26 @@ which is what a board reader means.

 Requirements: JDK 25 (set `JAVA_HOME` to it). The Gradle wrapper handles everything else.

-```
-./gradlew buildAllToOut
+```sh
+./gradlew buildAll
 ```

-builds every platform artifact into the workspace-level `../PluginOuts/` directory:
+This builds and verifies the Bukkit plugin, API, SPI and the Fabric, Forge and NeoForge jars
+for every Minecraft version declared in `gradle/mod-targets.json`. Artifacts stay in the
+producing module's `build/` directory. The packed Bukkit plugin is in `build/libs/`, the
+API is in `build/api/`, the SPI is in `spi/build/libs/`, and mod jars are in
+`adapters/<loader>/build/<minecraft>/libs/`.

-```
-Iris v<version> [CraftBukkit] <mc>.jar
-Iris v<version> [Fabric] <mc>+<loader>.jar
-Iris v<version> [Forge] <mc>+<loader>.jar
-Iris v<version> [NeoForge] <mc>+<loader>.jar
-```
+Use `./gradlew buildBukkit` for the plugin, or `verify<Loader><mc>` for one mod jar,
+for example `verifyFabric26_2` or `verifyNeoForge1_21_1`. `buildFabric`, `buildForge`
+and `buildNeoforge` select the `minecraftVersion` Gradle property. `./gradlew checkAll`
+runs every check plus the complete mod matrix. Forge 1.21.1 compiles its tests because
+Forge 52 cannot bootstrap Minecraft outside FML.

-Per-platform tasks: `./gradlew buildBukkit`, `buildFabric`, `buildForge`, `buildNeoforge`. The
-SPI jar (the pure-JVM adapter/platform contract, not the stable plugin API) is built to `spi/build/libs/` by
-`./gradlew :spi:jar`.
-
-`./gradlew buildAll` also runs `buildAllToOut` and copies the jars into a consumer dropin tree
-for a local test server. The consumer directory defaults to `../../[Minecraft Server]/consumers/`
-when it exists, otherwise `build/consumers/` inside the repo. `-Plocation=/path/to/consumers`
-changes only the consumer directory. Both tasks copy all four verified platform jars into
-`../PluginOuts/`.
+Multiplexor reads `gradle/multiplexor.gradle` to discover targets and build each in a
+separate source sandbox. Use its project build and deployment commands to export jars
+or install them into managed test instances. Gradle builds do not copy artifacts to
+external destinations.

 VolmLib is built from source when a `VolmLib` checkout sits beside the repo or in a parent directory
 (`VOLMLIB_DIR` or `-PlocalVolmLibDirectory=<path>` pick another one). Without one, or with
@@ -245,9 +245,15 @@ public class NativeStructurePostProcessorSurfaceTerrainTest {
            for (int y = groundY + 1; y <= groundY + 32; y++) {
                assertTrue("Roof at " + x + "," + y, state(blocks, x, y, 0).isAir());
            }
-            for (int y = 12; y < groundY; y++) {
+            int supportY = x < 2 ? groundY - 33 : 12;
+            for (int y = supportY; y < groundY; y++) {
                assertTrue("Missing foundation at " + x + "," + y, state(blocks, x, y, 0).isSolid());
            }
+            if (x < 2) {
+                for (int y = 13; y < supportY; y++) {
+                    assertTrue("Cave beneath support at " + x + "," + y, state(blocks, x, y, 0).isAir());
+                }
+            }
        }
    }

@@ -268,6 +274,57 @@ public class NativeStructurePostProcessorSurfaceTerrainTest {
        assertTrue(state(blocks, 0, groundY + 1, 0).isAir());
    }

+    @Test
+    public void flattenPreservesCavesBelowIntactGroundAtTheSkirtEdge() {
+        StructureStart start = desertStart();
+        int groundY = start.getBoundingBox().minY() - 1;
+        int x = start.getBoundingBox().maxX() + 23;
+        int z = start.getBoundingBox().minZ();
+        BoundingBox area = new BoundingBox(x, 0, z, x, 127, z);
+        Map<BlockPos, BlockState> blocks = new HashMap<>();
+        for (int y = groundY - 35; y <= groundY; y++) {
+            BlockState block = y >= groundY - 34 && y <= groundY - 13
+                    ? Blocks.CAVE_AIR.defaultBlockState() : Blocks.STONE.defaultBlockState();
+            put(blocks, x, y, z, block);
+        }
+        put(blocks, x, groundY - 1, z, Blocks.DIRT.defaultBlockState());
+        put(blocks, x, groundY, z, Blocks.GRASS_BLOCK.defaultBlockState());
+        NativeStructureTerrainIntegrator.TerrainTarget target = surfaceTarget(start, StructureTerrainMode.FLATTEN);
+        ((IrisStructureTerrain) target.terrain()).setHorizontalPadding(24).setFlattenRange(64);
+
+        NativeStructureSurfaceFitter.prepareSurfaceStructures(world(blocks), area, List.of(target), (px, pz) -> groundY);
+
+        for (int y = groundY - 34; y <= groundY - 13; y++) {
+            assertEquals("Cave at " + y, Blocks.CAVE_AIR.defaultBlockState(), state(blocks, x, y, z));
+        }
+        assertEquals(Blocks.DIRT.defaultBlockState(), state(blocks, x, groundY - 1, z));
+    }
+
+    @Test
+    public void flattenBridgesTheFoundationGapWithoutFillingACaveBelowItsSupport() {
+        StructureStart start = desertStart();
+        int groundY = start.getBoundingBox().minY() - 1;
+        BoundingBox area = new BoundingBox(0, 0, 0, 0, 127, 0);
+        Map<BlockPos, BlockState> blocks = new HashMap<>();
+        put(blocks, 0, groundY, 0, Blocks.GRASS_BLOCK.defaultBlockState());
+        for (int y = groundY - 11; y <= groundY - 9; y++) {
+            put(blocks, 0, y, 0, Blocks.STONE.defaultBlockState());
+        }
+        for (int y = groundY - 20; y <= groundY - 12; y++) {
+            put(blocks, 0, y, 0, Blocks.CAVE_AIR.defaultBlockState());
+        }
+
+        NativeStructureSurfaceFitter.prepareSurfaceStructures(world(blocks), area,
+                List.of(surfaceTarget(start, StructureTerrainMode.FLATTEN)), (x, z) -> groundY);
+
+        for (int y = groundY - 8; y < groundY; y++) {
+            assertEquals("Foundation at " + y, Blocks.STONE.defaultBlockState(), state(blocks, 0, y, 0));
+        }
+        for (int y = groundY - 20; y <= groundY - 12; y++) {
+            assertEquals("Cave at " + y, Blocks.CAVE_AIR.defaultBlockState(), state(blocks, 0, y, 0));
+        }
+    }
+
    @Test
    public void flattenLeavesBuriedAndSubmergedInstancesUntouched() {
        StructureStart start = desertStart();
@@ -619,10 +676,18 @@ public class NativeStructurePostProcessorSurfaceTerrainTest {
            for (int z = 0; z <= 8; z++) {
                int groundY = plan.flattenedHeights().get(NativeStructureTemplateOccupancy.columnKey(x, z)) - 1;
                assertTrue("Village grade at " + x + "," + z + ": " + groundY, groundY >= 64 && groundY <= 70);
-                for (int y = 20; y <= groundY; y++) {
+                boolean originalFoundation = (x == 0 || x == 8) && (z == 0 || z == 8);
+                int supportY = originalFoundation ? 63 : 20;
+                for (int y = supportY; y <= groundY; y++) {
                    assertTrue("Disconnected village ground at " + x + "," + y + "," + z,
                            state(blocks, x, y, z).isSolid());
                }
+                if (originalFoundation) {
+                    for (int y = 21; y < supportY; y++) {
+                        assertTrue("Cave beneath foundation at " + x + "," + y + "," + z,
+                                state(blocks, x, y, z).isAir());
+                    }
+                }
                for (int y = groundY + 1; y <= 96; y++) {
                    assertTrue("Roof remains above village at " + x + "," + y + "," + z,
                            state(blocks, x, y, z).isAir());
@@ -3,6 +3,7 @@ package art.arcane.iris.platform.bukkit.nms.v26_2_R1;
 import art.arcane.volmlib.nativelib.v26_2_R1.terrain.NativeStructureWorldgenAccess;

 import art.arcane.iris.structure.placement.IrisStructureTerrain;
+import art.arcane.volmlib.nativelib.terrain.NativeBlockChangeSet;
 import art.arcane.volmlib.util.structure.StructureTerrainMode;
 import art.arcane.volmlib.nativelib.minecraft26_2.terrain.NativeStructurePostProcessor;
 import art.arcane.volmlib.nativelib.minecraft26_2.terrain.NativeStructureTerrainIntegrator;
@@ -230,8 +231,9 @@ public class NativeStructureWorldgenAccessTest {
                recording.world(), generationCenter,
                (x, z) -> SURFACE_FIRST_FREE_Y,
                (x, z) -> FLOOR_FIRST_FREE_Y,
-                true,
-                position -> false);
+                true, true,
+                position -> false,
+                NativeBlockChangeSet.disabled());
        int x = generationCenter.getMiddleBlockX();
        int z = generationCenter.getMiddleBlockZ();

@@ -248,8 +250,9 @@ public class NativeStructureWorldgenAccessTest {
                recording.world(), generationCenter(),
                (x, z) -> SURFACE_FIRST_FREE_Y,
                (x, z) -> FLOOR_FIRST_FREE_Y,
-                false,
-                position::equals);
+                false, true,
+                position::equals,
+                NativeBlockChangeSet.disabled());

        assertSame(Blocks.DIRT, access.getBlockState(position).getBlock());
        assertFalse(access.ensureCanWrite(position));
@@ -319,8 +322,9 @@ public class NativeStructureWorldgenAccessTest {
                recording.world(), generationCenter(),
                (x, z) -> SURFACE_FIRST_FREE_Y,
                (x, z) -> FLOOR_FIRST_FREE_Y,
-                false,
-                position -> false);
+                false, true,
+                position -> false,
+                NativeBlockChangeSet.disabled());
    }

    private static ChunkPos generationCenter() {
@@ -9,6 +9,7 @@ import art.arcane.iris.structure.nativegen.NativeStructureVolumeIndex;
 import art.arcane.iris.generation.runtime.IrisEngine;
 import art.arcane.iris.generation.runtime.Engine;
 import art.arcane.volmlib.nativelib.terrain.structure.NativeStructureVolume;
+import art.arcane.volmlib.nativelib.terrain.structure.StructureTerrainSettings;
 import art.arcane.iris.world.history.GenerationHistoryRuntimeRouter;
 import art.arcane.volmlib.util.collection.KList;
 import net.minecraft.SharedConstants;
@@ -69,7 +70,8 @@ public class NativeStructureVolumeIndexTest {
        StructureStart start = swampHut(0, 0, 4, 6);
        BoundingBox bounds = start.getPieces().getFirst().getBoundingBox();

-        KList<NativeStructureVolume> volumes = NativeStructureVolumeSource.appendPieces(null, STRUCTURE_KEY, start);
+        KList<NativeStructureVolume> volumes = NativeStructureVolumeSource.appendPieces(null, STRUCTURE_KEY, start,
+                StructureTerrainSettings.SOURCE, (x, z) -> 63);

        assertEquals(1, volumes.size());
        NativeStructureVolume volume = volumes.getFirst();
@@ -84,8 +86,10 @@ public class NativeStructureVolumeIndexTest {

    @Test
    public void invalidStartsContributeNoVolumes() {
-        assertNull(NativeStructureVolumeSource.appendPieces(null, STRUCTURE_KEY, StructureStart.INVALID_START));
-        assertNull(NativeStructureVolumeSource.appendPieces(null, STRUCTURE_KEY, null));
+        assertNull(NativeStructureVolumeSource.appendPieces(null, STRUCTURE_KEY, StructureStart.INVALID_START,
+                StructureTerrainSettings.SOURCE, (x, z) -> 63));
+        assertNull(NativeStructureVolumeSource.appendPieces(null, STRUCTURE_KEY, null,
+                StructureTerrainSettings.SOURCE, (x, z) -> 63));
    }

    @Test
@@ -323,7 +327,7 @@ public class NativeStructureVolumeIndexTest {
        BlockingResolver coordination = new BlockingResolver();
        NativeStructureVolumeIndex.OriginResolver volumes = (engine, chunkX, chunkZ) ->
                new KList<>(new NativeStructureVolume(chunkX + ":" + chunkZ,
-                        -256, 0, -256, 256, 255, 256));
+                        -256, 0, -256, 256, 255, 256, null));
        NativeStructureVolumeIndex index = NativeStructureVolumeIndex.forTesting((engine, chunkX, chunkZ) -> {
            coordination.volumesAt(engine, chunkX, chunkZ);
            return volumes.volumesAt(engine, chunkX, chunkZ);
@@ -369,7 +373,7 @@ public class NativeStructureVolumeIndexTest {
                terrain.join();
            }
            return new KList<>(new NativeStructureVolume(chunkX + ":" + chunkZ,
-                    -256, 0, -256, 256, 100, 256));
+                    -256, 0, -256, 256, 100, 256, null));
        });
        ExecutorService owner = Executors.newSingleThreadExecutor();
        ForkJoinPool workers = new ForkJoinPool(2);
@@ -493,7 +497,13 @@ public class NativeStructureVolumeIndexTest {
    private static Map<?, ?> cache(NativeStructureVolumeIndex index, String name) throws Exception {
        Field field = NativeStructureVolumeIndex.class.getDeclaredField(name);
        field.setAccessible(true);
-        return (Map<?, ?>) field.get(index);
+        Object value = field.get(index);
+        if (value instanceof Map<?, ?> map) {
+            return map;
+        }
+        Field entries = value.getClass().getDeclaredField("entries");
+        entries.setAccessible(true);
+        return (Map<?, ?>) entries.get(value);
    }

    private static StructureStart swampHut(int chunkX, int chunkZ, int x, int z) {
@@ -544,7 +554,8 @@ public class NativeStructureVolumeIndexTest {
            if (chunkX != originChunkX || chunkZ != originChunkZ) {
                return NativeStructureVolume.NONE;
            }
-            return NativeStructureVolumeSource.appendPieces(null, STRUCTURE_KEY, swampHut(chunkX, chunkZ, 4, 6));
+            return NativeStructureVolumeSource.appendPieces(null, STRUCTURE_KEY, swampHut(chunkX, chunkZ, 4, 6),
+                    StructureTerrainSettings.SOURCE, (x, z) -> 63);
        }
    }

@@ -596,7 +607,7 @@ public class NativeStructureVolumeIndexTest {
            return new KList<>(new NativeStructureVolume(
                    chunkX + ":" + chunkZ,
                    0, 0, 0,
-                    15, 255, 15));
+                    15, 255, 15, null));
        }
    }
    private record ScopedEngine(IrisEngine engine, AtomicInteger scopes) {
@@ -2,8 +2,9 @@ package art.arcane.iris.probe;

 import art.arcane.iris.configuration.IrisSettings;
 import art.arcane.iris.generation.concurrent.MultiBurst;
-import art.arcane.iris.generation.hydrology.HydrologyTileCache;
-import art.arcane.iris.generation.hydrology.runtime.IrisHydrologyRuntime;
+import art.arcane.iris.generation.hydrology.engine.HydrologyPregeneration;
+import art.arcane.iris.generation.hydrology.plan.WindowKey;
+import art.arcane.iris.world.pregen.PregenHydrology;
 import art.arcane.iris.world.pregen.PregenPerformanceProfile;

 import net.minecraft.core.registries.Registries;
@@ -31,11 +32,16 @@ import java.nio.file.Path;
 import java.nio.file.StandardCopyOption;
 import java.nio.file.StandardOpenOption;
 import java.security.MessageDigest;
+import java.util.ArrayList;
+import java.util.HashSet;
 import java.util.HexFormat;
 import java.util.List;
 import java.util.Locale;
+import java.util.Set;

 public final class OfflineRegionGenerator {
+    private static final int CHUNKS_PER_HYDROLOGY_REGION = WindowKey.SIZE >> 4;
+
    private OfflineRegionGenerator() {
    }

@@ -97,14 +103,13 @@ public final class OfflineRegionGenerator {
            PregenPerformanceProfile.apply(session.engine());
            System.out.println("generationProfile=pregen noiseCacheSize=" + IrisSettings.get().getPerformance().getNoiseCacheSize()
                    + " burstParallelism=" + MultiBurst.burst.parallelism() + " multicore=true");
-            IrisHydrologyRuntime hydrology = session.engine().getComplex().getHydrologyRuntime();
-            try (HydrologyTileCache.PregenerationScope hydrologyScope = hydrology == null ? null
-                    : hydrology.preparePregeneration(configuration.hydrologyArea());
+            try (HydrologyPregeneration pregeneration = PregenHydrology.open(session.engine());
                 HeadlessTerrainContext context = HeadlessTerrainContext.create(new HeadlessTerrainContext.Options(
                    session.engine(), runtime, staged.resolve("templates"), configuration.levelKey(),
                    configuration.noiseSettings(), spigot));
                 RegionGenerationWindow workers = new RegionGenerationWindow(configuration.parallelism(),
                         RegionGenerationWindow.Policy.STANDALONE)) {
+                PregenHydrology.prepareAll(pregeneration, configuration.hydrologyRegions());
                HeadlessRegionTerrain.Session rolling = new HeadlessRegionTerrain.Session(workers);
                Path regionDirectory = session.engine().getTarget().getWorld().worldFolder().toPath().resolve("region");
                Files.createDirectory(regionDirectory);
@@ -239,14 +244,27 @@ public final class OfflineRegionGenerator {
            }
        }

-        HydrologyTileCache.PregenerationArea hydrologyArea() {
+        List<long[]> hydrologyRegions() {
            int halo = NativeRegionPlan.terrainHalo();
-            long minimumX = ((long) chunkX - halo) * 16L;
-            long minimumZ = ((long) chunkZ - halo) * 16L;
-            long maximumX = ((long) chunkX + (long) width * regionsX + halo) * 16L - 1L;
-            long maximumZ = ((long) chunkZ + (long) width * regionsZ + halo) * 16L - 1L;
-            return new HydrologyTileCache.PregenerationArea(Math.toIntExact((minimumX + maximumX) / 2L),
-                    Math.toIntExact((minimumZ + maximumZ) / 2L), minimumX, minimumZ, maximumX, maximumZ);
+            Set<Long> seen = new HashSet<>();
+            List<long[]> regions = new ArrayList<>();
+            for (int row = 0; row < regionsZ; row++) {
+                for (int column = 0; column < regionsX; column++) {
+                    int regionX = row % 2 == 0 ? column : regionsX - column - 1;
+                    int minimumX = Math.floorDiv(chunkX + regionX * width - halo, CHUNKS_PER_HYDROLOGY_REGION);
+                    int maximumX = Math.floorDiv(chunkX + (regionX + 1) * width - 1 + halo, CHUNKS_PER_HYDROLOGY_REGION);
+                    int minimumZ = Math.floorDiv(chunkZ + row * width - halo, CHUNKS_PER_HYDROLOGY_REGION);
+                    int maximumZ = Math.floorDiv(chunkZ + (row + 1) * width - 1 + halo, CHUNKS_PER_HYDROLOGY_REGION);
+                    for (int hydrologyZ = minimumZ; hydrologyZ <= maximumZ; hydrologyZ++) {
+                        for (int hydrologyX = minimumX; hydrologyX <= maximumX; hydrologyX++) {
+                            if (seen.add(((long) hydrologyX << 32) | (hydrologyZ & 0xFFFFFFFFL))) {
+                                regions.add(new long[]{hydrologyX, hydrologyZ});
+                            }
+                        }
+                    }
+                }
+            }
+            return regions;
        }

        static Configuration parse(String[] arguments) throws IOException {
@@ -14,6 +14,7 @@ import net.minecraft.SharedConstants;
 import net.minecraft.server.Bootstrap;
 import net.minecraft.world.level.LevelHeightAccessor;
 import net.minecraft.world.level.levelgen.Heightmap;
+import org.junit.AfterClass;
 import org.junit.BeforeClass;
 import org.junit.Rule;
 import org.junit.Test;
@@ -45,6 +46,11 @@ public final class IrisChunkGeneratorHeightCacheTest {
        NativeBlockTags.bindHeightmapFixtures();
    }

+    @AfterClass
+    public static void restoreBlockTags() {
+        NativeBlockTags.restoreTags();
+    }
+
    @Test
    public void repeatedNativeHeightUsesLiveHeightQueriesAcrossRuntimeChanges() throws Exception {
        Fixture fixture = fixture();
@@ -245,9 +245,15 @@ public class NativeStructurePostProcessorSurfaceTerrainTest {
            for (int y = groundY + 1; y <= groundY + 32; y++) {
                assertTrue("Roof at " + x + "," + y, state(blocks, x, y, 0).isAir());
            }
-            for (int y = 12; y < groundY; y++) {
+            int supportY = x < 2 ? groundY - 33 : 12;
+            for (int y = supportY; y < groundY; y++) {
                assertTrue("Missing foundation at " + x + "," + y, state(blocks, x, y, 0).isSolid());
            }
+            if (x < 2) {
+                for (int y = 13; y < supportY; y++) {
+                    assertTrue("Cave beneath support at " + x + "," + y, state(blocks, x, y, 0).isAir());
+                }
+            }
        }
    }

@@ -268,6 +274,57 @@ public class NativeStructurePostProcessorSurfaceTerrainTest {
        assertTrue(state(blocks, 0, groundY + 1, 0).isAir());
    }

+    @Test
+    public void flattenPreservesCavesBelowIntactGroundAtTheSkirtEdge() {
+        StructureStart start = desertStart();
+        int groundY = start.getBoundingBox().minY() - 1;
+        int x = start.getBoundingBox().maxX() + 23;
+        int z = start.getBoundingBox().minZ();
+        BoundingBox area = new BoundingBox(x, 0, z, x, 127, z);
+        Map<BlockPos, BlockState> blocks = new HashMap<>();
+        for (int y = groundY - 35; y <= groundY; y++) {
+            BlockState block = y >= groundY - 34 && y <= groundY - 13
+                    ? Blocks.CAVE_AIR.defaultBlockState() : Blocks.STONE.defaultBlockState();
+            put(blocks, x, y, z, block);
+        }
+        put(blocks, x, groundY - 1, z, Blocks.DIRT.defaultBlockState());
+        put(blocks, x, groundY, z, Blocks.GRASS_BLOCK.defaultBlockState());
+        NativeStructureTerrainIntegrator.TerrainTarget target = surfaceTarget(start, StructureTerrainMode.FLATTEN);
+        ((IrisStructureTerrain) target.terrain()).setHorizontalPadding(24).setFlattenRange(64);
+
+        NativeStructureSurfaceFitter.prepareSurfaceStructures(world(blocks), area, List.of(target), (px, pz) -> groundY);
+
+        for (int y = groundY - 34; y <= groundY - 13; y++) {
+            assertEquals("Cave at " + y, Blocks.CAVE_AIR.defaultBlockState(), state(blocks, x, y, z));
+        }
+        assertEquals(Blocks.DIRT.defaultBlockState(), state(blocks, x, groundY - 1, z));
+    }
+
+    @Test
+    public void flattenBridgesTheFoundationGapWithoutFillingACaveBelowItsSupport() {
+        StructureStart start = desertStart();
+        int groundY = start.getBoundingBox().minY() - 1;
+        BoundingBox area = new BoundingBox(0, 0, 0, 0, 127, 0);
+        Map<BlockPos, BlockState> blocks = new HashMap<>();
+        put(blocks, 0, groundY, 0, Blocks.GRASS_BLOCK.defaultBlockState());
+        for (int y = groundY - 11; y <= groundY - 9; y++) {
+            put(blocks, 0, y, 0, Blocks.STONE.defaultBlockState());
+        }
+        for (int y = groundY - 20; y <= groundY - 12; y++) {
+            put(blocks, 0, y, 0, Blocks.CAVE_AIR.defaultBlockState());
+        }
+
+        NativeStructureSurfaceFitter.prepareSurfaceStructures(world(blocks), area,
+                List.of(surfaceTarget(start, StructureTerrainMode.FLATTEN)), (x, z) -> groundY);
+
+        for (int y = groundY - 8; y < groundY; y++) {
+            assertEquals("Foundation at " + y, Blocks.STONE.defaultBlockState(), state(blocks, 0, y, 0));
+        }
+        for (int y = groundY - 20; y <= groundY - 12; y++) {
+            assertEquals("Cave at " + y, Blocks.CAVE_AIR.defaultBlockState(), state(blocks, 0, y, 0));
+        }
+    }
+
    @Test
    public void flattenLeavesBuriedAndSubmergedInstancesUntouched() {
        StructureStart start = desertStart();
@@ -619,10 +676,18 @@ public class NativeStructurePostProcessorSurfaceTerrainTest {
            for (int z = 0; z <= 8; z++) {
                int groundY = plan.flattenedHeights().get(NativeStructureTemplateOccupancy.columnKey(x, z)) - 1;
                assertTrue("Village grade at " + x + "," + z + ": " + groundY, groundY >= 64 && groundY <= 70);
-                for (int y = 20; y <= groundY; y++) {
+                boolean originalFoundation = (x == 0 || x == 8) && (z == 0 || z == 8);
+                int supportY = originalFoundation ? 63 : 20;
+                for (int y = supportY; y <= groundY; y++) {
                    assertTrue("Disconnected village ground at " + x + "," + y + "," + z,
                            state(blocks, x, y, z).isSolid());
                }
+                if (originalFoundation) {
+                    for (int y = 21; y < supportY; y++) {
+                        assertTrue("Cave beneath foundation at " + x + "," + y + "," + z,
+                                state(blocks, x, y, z).isAir());
+                    }
+                }
                for (int y = groundY + 1; y <= 96; y++) {
                    assertTrue("Roof remains above village at " + x + "," + y + "," + z,
                            state(blocks, x, y, z).isAir());
@@ -20,6 +20,7 @@ import net.minecraft.world.level.block.Blocks;
 import net.minecraft.world.level.block.RotatedPillarBlock;
 import net.minecraft.world.level.block.LiquidBlock;
 import net.minecraft.world.level.levelgen.Heightmap;
+import org.junit.AfterClass;
 import org.junit.BeforeClass;
 import org.junit.Rule;
 import org.junit.Test;
@@ -46,6 +47,11 @@ public final class NativeTransitionColumnTest {
        NativeBlockTags.bindHeightmapFixtures();
    }

+    @AfterClass
+    public static void restoreBlockTags() {
+        NativeBlockTags.restoreTags();
+    }
+
    @Test
    public void customKeysUseCarrierForNativeColumnsAndHeightmaps() {
        String key = "itemsadder:rocks/ruby_ore";
@@ -1,21 +1,30 @@
 package art.arcane.iris.nativegen.v26_3_R1;

 import net.minecraft.core.Holder;
+import net.minecraft.core.HolderSet;
 import net.minecraft.core.registries.BuiltInRegistries;
 import net.minecraft.core.registries.Registries;
 import net.minecraft.tags.BlockTags;
 import net.minecraft.tags.TagLoader;
+import net.minecraft.tags.TagKey;
 import net.minecraft.world.level.block.Block;
 import net.minecraft.world.level.block.Blocks;

+import java.util.HashMap;
 import java.util.List;
 import java.util.Map;

 public final class NativeBlockTags {
+    private static Map<TagKey<Block>, List<Holder<Block>>> originalTags;
+
    private NativeBlockTags() {
    }

    public static void bindHeightmapFixtures() {
+        originalTags = new HashMap<>();
+        for (HolderSet.Named<Block> tag : BuiltInRegistries.BLOCK.getTags().toList()) {
+            originalTags.put(tag.key(), tag.stream().toList());
+        }
        List<Holder<Block>> solid = List.of(Blocks.STONE.builtInRegistryHolder(),
                Blocks.OAK_LOG.builtInRegistryHolder(), Blocks.SPRUCE_LOG.builtInRegistryHolder());
        List<Holder<Block>> canopy = List.of(Blocks.STONE.builtInRegistryHolder(),
@@ -25,4 +34,12 @@ public final class NativeBlockTags {
                BlockTags.BLOCKS_MOTION_IN_HEIGHTMAP, canopy,
                BlockTags.BLOCKS_MOTION_IN_HEIGHTMAP_NO_LEAVES, solid))).apply();
    }
+
+    public static void restoreTags() {
+        if (originalTags == null) {
+            return;
+        }
+        BuiltInRegistries.BLOCK.prepareTagReload(new TagLoader.LoadResult<>(Registries.BLOCK, originalTags)).apply();
+        originalTags = null;
+    }
 }
@@ -3,6 +3,7 @@ package art.arcane.iris.platform.bukkit.nms.v26_3_R1;
 import art.arcane.volmlib.nativelib.v26_3_R1.terrain.NativeStructureWorldgenAccess;

 import art.arcane.iris.structure.placement.IrisStructureTerrain;
+import art.arcane.volmlib.nativelib.terrain.NativeBlockChangeSet;
 import art.arcane.volmlib.util.structure.StructureTerrainMode;
 import art.arcane.volmlib.nativelib.v26_3_R1.terrain.NativeStructurePostProcessor;
 import art.arcane.volmlib.nativelib.v26_3_R1.terrain.NativeStructureTerrainIntegrator;
@@ -230,8 +231,9 @@ public class NativeStructureWorldgenAccessTest {
                recording.world(), generationCenter,
                (x, z) -> SURFACE_FIRST_FREE_Y,
                (x, z) -> FLOOR_FIRST_FREE_Y,
-                true,
-                position -> false);
+                true, true,
+                position -> false,
+                NativeBlockChangeSet.disabled());
        int x = generationCenter.getMiddleBlockX();
        int z = generationCenter.getMiddleBlockZ();

@@ -248,8 +250,9 @@ public class NativeStructureWorldgenAccessTest {
                recording.world(), generationCenter(),
                (x, z) -> SURFACE_FIRST_FREE_Y,
                (x, z) -> FLOOR_FIRST_FREE_Y,
-                false,
-                position::equals);
+                false, true,
+                position::equals,
+                NativeBlockChangeSet.disabled());

        assertSame(Blocks.DIRT, access.getBlockState(position).getBlock());
        assertFalse(access.ensureCanWrite(position));
@@ -319,8 +322,9 @@ public class NativeStructureWorldgenAccessTest {
                recording.world(), generationCenter(),
                (x, z) -> SURFACE_FIRST_FREE_Y,
                (x, z) -> FLOOR_FIRST_FREE_Y,
-                false,
-                position -> false);
+                false, true,
+                position -> false,
+                NativeBlockChangeSet.disabled());
    }

    private static ChunkPos generationCenter() {
@@ -34,6 +34,7 @@ import net.minecraft.world.level.levelgen.structure.pieces.PiecesContainer;
 import net.minecraft.world.level.levelgen.structure.structures.IglooPieces;
 import net.minecraft.world.level.levelgen.structure.structures.SwampHutPiece;
 import net.minecraft.world.level.levelgen.structure.structures.SwampHutStructure;
+import org.junit.AfterClass;
 import org.junit.BeforeClass;
 import org.junit.Test;

@@ -68,6 +69,11 @@ public class WorldgenTerrainHeightmapsTest {
        NativeBlockTags.bindHeightmapFixtures();
    }

+    @AfterClass
+    public static void restoreBlockTags() {
+        NativeBlockTags.restoreTags();
+    }
+
    @Test
    public void authoringHeightmapsReadPlacedObjectsAndFluidsWithoutTerrainResolvers() {
        ProtoChunk chunk = terrainChunk(new ChunkPos(0, 0));
@@ -13,6 +13,7 @@ import com.google.gson.JsonParser;
 import org.bukkit.Bukkit;
 import org.junit.AfterClass;
 import org.junit.BeforeClass;
+import org.junit.ClassRule;
 import org.junit.Test;

 import java.io.File;
@@ -26,6 +27,9 @@ import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertThrows;

 public final class BareMobSpawnHistoryTest {
+    @ClassRule
+    public static final PaperRegistryIsolation registryIsolation = new PaperRegistryIsolation();
+
    private static final String LEGACY_RENDERER_IDENTITY = "bukkit-v26_3_R1-generated-registry-json-v1";
    private static final String NATURAL_MOB_SPAWNS = "minecraft:gameplay/natural_mob_spawns";
    private static final GenerationRegistryContract.PhysicalResourceKey INSTALLED =
@@ -29,6 +29,7 @@ import net.minecraft.world.level.levelgen.structure.StructureStart;
 import net.minecraft.world.level.levelgen.structure.templatesystem.StructureTemplateManager;
 import net.minecraft.world.level.storage.LevelStorageSource;
 import org.junit.Rule;
+import org.junit.ClassRule;
 import org.junit.Test;
 import org.junit.rules.TemporaryFolder;
 import org.bukkit.craftbukkit.generator.CustomChunkGenerator;
@@ -49,6 +50,9 @@ import static org.mockito.Mockito.spy;
 import static org.mockito.Mockito.verify;

 public class HeadlessChunkGeneratorTest {
+    @ClassRule
+    public static final PaperRegistryIsolation registryIsolation = new PaperRegistryIsolation();
+
    @Rule
    public TemporaryFolder temporary = new TemporaryFolder();

@@ -133,7 +137,7 @@ public class HeadlessChunkGeneratorTest {
        }
        Files.writeString(pack.resolve("dimensions/main.json"), """
                {"name":"Native columns","focus":"swamp","regions":["owned"],"fluidHeight":40,"logicalHeight":256,
-                 "landChance":1,"carvingEnabled":false,"hydrology":{"rivers":{"enabled":false}}}
+                 "landChance":1,"carvingEnabled":false}
                """);
        Files.writeString(pack.resolve("regions/owned.json"), "{\"landBiomes\":[\"swamp\"]}");
        Files.writeString(pack.resolve("generators/flat.json"), "{\"composite\":[]}");
@@ -31,6 +31,7 @@ import net.minecraft.world.level.levelgen.structure.templatesystem.StructureTemp
 import net.minecraft.world.level.storage.LevelStorageSource;
 import org.bukkit.Bukkit;
 import org.junit.Rule;
+import org.junit.ClassRule;
 import org.junit.Test;
 import org.junit.rules.TemporaryFolder;

@@ -48,6 +49,9 @@ import static org.junit.Assert.assertThrows;
 import static org.junit.Assert.assertTrue;

 public final class HeadlessChunkLightingTest {
+    @ClassRule
+    public static final PaperRegistryIsolation registryIsolation = new PaperRegistryIsolation();
+
    @Rule
    public TemporaryFolder temporary = new TemporaryFolder();

@@ -38,6 +38,7 @@ import net.minecraft.world.ticks.ScheduledTick;
 import org.bukkit.NamespacedKey;
 import org.bukkit.persistence.PersistentDataType;
 import org.junit.Rule;
+import org.junit.ClassRule;
 import org.junit.Test;
 import org.junit.rules.TemporaryFolder;

@@ -54,6 +55,9 @@ import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;

 public class HeadlessChunkSerializationTest {
+    @ClassRule
+    public static final PaperRegistryIsolation registryIsolation = new PaperRegistryIsolation();
+
    @Rule
    public TemporaryFolder temporary = new TemporaryFolder();

@@ -9,6 +9,7 @@ import net.minecraft.world.item.Items;

 import java.util.Map;
 import net.minecraft.world.level.block.Blocks;
+import org.junit.ClassRule;
 import org.junit.Test;
 import org.bukkit.Bukkit;

@@ -18,6 +19,9 @@ import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;

 public final class HeadlessNativeBootstrapTest {
+    @ClassRule
+    public static final PaperRegistryIsolation registryIsolation = new PaperRegistryIsolation();
+
    @Test
    public void bindsNativeItemComponentsWithoutStartingServer() throws Exception {
        HeadlessNativeBootstrap.bindComponents(HeadlessNativeTestRegistries.get());
@@ -7,12 +7,16 @@ import net.minecraft.resources.Identifier;
 import net.minecraft.resources.ResourceKey;
 import net.minecraft.world.level.biome.Biome;
 import net.minecraft.world.level.levelgen.structure.Structure;
+import org.junit.ClassRule;
 import org.junit.Test;


 import static org.junit.Assert.assertTrue;

 public final class HeadlessNativeRegistriesTest {
+    @ClassRule
+    public static final PaperRegistryIsolation registryIsolation = new PaperRegistryIsolation();
+
    @Test
    public void nativeStructureBiomeTagsUseTheLoadedBiomeHolders() throws Exception {
        RegistryAccess registries = HeadlessNativeTestRegistries.get();
@@ -4,6 +4,7 @@ import art.arcane.volmlib.nativelib.minecraft26_2.modded.NativeRegistryAccess;
 import net.minecraft.core.registries.Registries;
 import org.bukkit.Bukkit;
 import org.junit.BeforeClass;
+import org.junit.ClassRule;
 import org.junit.Test;

 import java.util.Map;
@@ -17,6 +18,9 @@ import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertThrows;

 public final class HeadlessNativeRegistryTest {
+    @ClassRule
+    public static final PaperRegistryIsolation registryIsolation = new PaperRegistryIsolation();
+
    @BeforeClass
    public static void bootstrap() {
        HeadlessNativeBootstrap.initialize();
@@ -11,6 +11,7 @@ import art.arcane.volmlib.nativelib.minecraft26_2.modded.NativeTileReader;
 import net.minecraft.nbt.CompoundTag;
 import net.minecraft.data.registries.VanillaRegistries;
 import org.junit.BeforeClass;
+import org.junit.ClassRule;
 import org.junit.Test;

 import java.io.ByteArrayInputStream;
@@ -23,6 +24,9 @@ import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertThrows;

 public final class HeadlessNativeTileTest {
+    @ClassRule
+    public static final PaperRegistryIsolation registryIsolation = new PaperRegistryIsolation();
+
    @BeforeClass
    public static void bootstrap() {
        HeadlessNativeBootstrap.initialize();
@@ -1,7 +1,6 @@
 package art.arcane.iris.probe;

 import art.arcane.iris.structure.nativegen.NativeStructureVolumeIndex;
-import art.arcane.iris.generation.hydrology.HydrologyTileCache;
 import art.arcane.volmlib.nativelib.terrain.structure.NativeStructureVolume;
 import art.arcane.volmlib.util.collection.KList;
 import net.minecraft.nbt.CompoundTag;
@@ -17,6 +16,7 @@ import org.bukkit.Bukkit;
 import org.bukkit.NamespacedKey;
 import org.bukkit.persistence.PersistentDataType;
 import org.junit.Rule;
+import org.junit.ClassRule;
 import org.junit.Test;
 import org.junit.rules.TemporaryFolder;
 import org.spigotmc.SpigotWorldConfig;
@@ -36,6 +36,9 @@ import static org.junit.Assert.assertSame;
 import static org.junit.Assert.assertTrue;

 public final class HeadlessRegionTerrainTest {
+    @ClassRule
+    public static final PaperRegistryIsolation registryIsolation = new PaperRegistryIsolation();
+
    @Rule
    public TemporaryFolder temporary = new TemporaryFolder();

@@ -64,11 +67,10 @@ public final class HeadlessRegionTerrainTest {
                OfflineRegionGenerator.Configuration export = new OfflineRegionGenerator.Configuration(
                        workspace.pack(), "main", 69420L, -3, 2, 1, 2, 3, 4, configuration,
                        "probe", Level.OVERWORLD, NoiseGeneratorSettings.OVERWORLD, root.resolve("export"));
-                HydrologyTileCache.PregenerationArea bounds = export.hydrologyArea();
-                assertEquals(-80L, bounds.minimumBlockX());
-                assertEquals(0L, bounds.minimumBlockZ());
-                assertEquals(15L, bounds.maximumBlockX());
-                assertEquals(111L, bounds.maximumBlockZ());
+                List<long[]> regions = export.hydrologyRegions();
+                assertEquals(2, regions.size());
+                assertArrayEquals(new long[]{-1L, 0L}, regions.get(0));
+                assertArrayEquals(new long[]{0L, 0L}, regions.get(1));
                assertEquals(1, result.targetChunks());
                assertEquals(529, result.chunks().size());
                long terrain = result.chunks().stream().filter(chunk -> chunk.getPersistedStatus() == ChunkStatus.TERRAIN).count();
@@ -185,7 +187,7 @@ public final class HeadlessRegionTerrainTest {
        }
        Files.writeString(pack.resolve("dimensions/main.json"), """
                {"name":"Native region","focus":"swamp","regions":["owned"],"fluidHeight":40,"logicalHeight":256,
-                 "landChance":1,"carvingEnabled":false,"hydrology":{"rivers":{"enabled":false}}}
+                 "landChance":1,"carvingEnabled":false}
                """);
        Files.writeString(pack.resolve("regions/owned.json"), "{\"landBiomes\":[\"swamp\"]}");
        Files.writeString(pack.resolve("generators/flat.json"), "{\"composite\":[]}");
@@ -24,6 +24,7 @@ import net.minecraft.world.level.block.state.BlockState;
 import net.minecraft.world.level.chunk.storage.RegionFile;
 import net.minecraft.world.level.chunk.storage.RegionStorageInfo;
 import org.junit.BeforeClass;
+import org.junit.ClassRule;
 import org.junit.Test;

 import java.io.DataInputStream;
@@ -38,6 +39,9 @@ import static org.junit.Assert.assertThrows;
 import static org.junit.Assert.assertTrue;

 public final class NativeRegionTerrainWriterTest {
+    @ClassRule
+    public static final PaperRegistryIsolation registryIsolation = new PaperRegistryIsolation();
+
    @BeforeClass
    public static void bootstrap() {
        SharedConstants.tryDetectVersion();
@@ -26,6 +26,7 @@ import net.minecraft.world.level.material.Fluids;
 import org.bukkit.Bukkit;
 import org.junit.AfterClass;
 import org.junit.BeforeClass;
+import org.junit.ClassRule;
 import org.junit.Test;

 import java.util.ArrayList;
@@ -40,6 +41,9 @@ import static org.junit.Assert.assertThrows;
 import static org.junit.Assert.assertTrue;

 public final class OfflineNativeFeatureFeasibilityTest {
+    @ClassRule
+    public static final PaperRegistryIsolation registryIsolation = new PaperRegistryIsolation();
+
    private static HeadlessNativeRegistries loaded;
    private static RegistryAccess registries;
    private static DimensionType dimension;
@@ -1,6 +1,7 @@
 package art.arcane.iris.probe;

 import org.junit.Rule;
+import org.junit.ClassRule;
 import org.junit.Test;
 import org.junit.rules.TemporaryFolder;
 import org.mockito.MockedStatic;
@@ -22,6 +23,9 @@ import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.mockStatic;

 public final class OfflineRegionPublicationTest {
+    @ClassRule
+    public static final PaperRegistryIsolation registryIsolation = new PaperRegistryIsolation();
+
    @Rule
    public TemporaryFolder temporary = new TemporaryFolder();

@@ -0,0 +1,37 @@
+package art.arcane.iris.probe;
+
+import io.papermc.paper.registry.PaperRegistryAccess;
+import org.junit.rules.TestRule;
+import org.junit.runner.Description;
+import org.junit.runners.model.Statement;
+
+import java.lang.reflect.Field;
+import java.util.HashMap;
+import java.util.Map;
+
+public final class PaperRegistryIsolation implements TestRule {
+    @Override
+    public Statement apply(Statement base, Description description) {
+        return new Statement() {
+            @Override
+            public void evaluate() throws Throwable {
+                Map<Object, Object> registries = registries();
+                Map<Object, Object> previous = new HashMap<>(registries);
+                registries.clear();
+                try {
+                    base.evaluate();
+                } finally {
+                    registries.clear();
+                    registries.putAll(previous);
+                }
+            }
+        };
+    }
+
+    @SuppressWarnings("unchecked")
+    private static Map<Object, Object> registries() throws ReflectiveOperationException {
+        Field field = PaperRegistryAccess.class.getDeclaredField("registries");
+        field.setAccessible(true);
+        return (Map<Object, Object>) field.get(PaperRegistryAccess.instance());
+    }
+}
@@ -9,6 +9,7 @@ import art.arcane.iris.structure.nativegen.NativeStructureVolumeIndex;
 import art.arcane.iris.generation.runtime.IrisEngine;
 import art.arcane.iris.generation.runtime.Engine;
 import art.arcane.volmlib.nativelib.terrain.structure.NativeStructureVolume;
+import art.arcane.volmlib.nativelib.terrain.structure.StructureTerrainSettings;
 import art.arcane.iris.world.history.GenerationHistoryRuntimeRouter;
 import art.arcane.volmlib.util.collection.KList;
 import net.minecraft.SharedConstants;
@@ -69,7 +70,8 @@ public class NativeStructureVolumeIndexTest {
        StructureStart start = swampHut(0, 0, 4, 6);
        BoundingBox bounds = start.getPieces().getFirst().getBoundingBox();

-        KList<NativeStructureVolume> volumes = NativeStructureVolumeSource.appendPieces(null, STRUCTURE_KEY, start);
+        KList<NativeStructureVolume> volumes = NativeStructureVolumeSource.appendPieces(null, STRUCTURE_KEY, start,
+                StructureTerrainSettings.SOURCE, (x, z) -> 63);

        assertEquals(1, volumes.size());
        NativeStructureVolume volume = volumes.getFirst();
@@ -84,8 +86,10 @@ public class NativeStructureVolumeIndexTest {

    @Test
    public void invalidStartsContributeNoVolumes() {
-        assertNull(NativeStructureVolumeSource.appendPieces(null, STRUCTURE_KEY, StructureStart.INVALID_START));
-        assertNull(NativeStructureVolumeSource.appendPieces(null, STRUCTURE_KEY, null));
+        assertNull(NativeStructureVolumeSource.appendPieces(null, STRUCTURE_KEY, StructureStart.INVALID_START,
+                StructureTerrainSettings.SOURCE, (x, z) -> 63));
+        assertNull(NativeStructureVolumeSource.appendPieces(null, STRUCTURE_KEY, null,
+                StructureTerrainSettings.SOURCE, (x, z) -> 63));
    }

    @Test
@@ -323,7 +327,7 @@ public class NativeStructureVolumeIndexTest {
        BlockingResolver coordination = new BlockingResolver();
        NativeStructureVolumeIndex.OriginResolver volumes = (engine, chunkX, chunkZ) ->
                new KList<>(new NativeStructureVolume(chunkX + ":" + chunkZ,
-                        -256, 0, -256, 256, 255, 256));
+                        -256, 0, -256, 256, 255, 256, null));
        NativeStructureVolumeIndex index = NativeStructureVolumeIndex.forTesting((engine, chunkX, chunkZ) -> {
            coordination.volumesAt(engine, chunkX, chunkZ);
            return volumes.volumesAt(engine, chunkX, chunkZ);
@@ -369,7 +373,7 @@ public class NativeStructureVolumeIndexTest {
                terrain.join();
            }
            return new KList<>(new NativeStructureVolume(chunkX + ":" + chunkZ,
-                    -256, 0, -256, 256, 100, 256));
+                    -256, 0, -256, 256, 100, 256, null));
        });
        ExecutorService owner = Executors.newSingleThreadExecutor();
        ForkJoinPool workers = new ForkJoinPool(2);
@@ -493,7 +497,13 @@ public class NativeStructureVolumeIndexTest {
    private static Map<?, ?> cache(NativeStructureVolumeIndex index, String name) throws Exception {
        Field field = NativeStructureVolumeIndex.class.getDeclaredField(name);
        field.setAccessible(true);
-        return (Map<?, ?>) field.get(index);
+        Object value = field.get(index);
+        if (value instanceof Map<?, ?> map) {
+            return map;
+        }
+        Field entries = value.getClass().getDeclaredField("entries");
+        entries.setAccessible(true);
+        return (Map<?, ?>) entries.get(value);
    }

    private static StructureStart swampHut(int chunkX, int chunkZ, int x, int z) {
@@ -544,7 +554,8 @@ public class NativeStructureVolumeIndexTest {
            if (chunkX != originChunkX || chunkZ != originChunkZ) {
                return NativeStructureVolume.NONE;
            }
-            return NativeStructureVolumeSource.appendPieces(null, STRUCTURE_KEY, swampHut(chunkX, chunkZ, 4, 6));
+            return NativeStructureVolumeSource.appendPieces(null, STRUCTURE_KEY, swampHut(chunkX, chunkZ, 4, 6),
+                    StructureTerrainSettings.SOURCE, (x, z) -> 63);
        }
    }

@@ -596,7 +607,7 @@ public class NativeStructureVolumeIndexTest {
            return new KList<>(new NativeStructureVolume(
                    chunkX + ":" + chunkZ,
                    0, 0, 0,
-                    15, 255, 15));
+                    15, 255, 15, null));
        }
    }
    private record ScopedEngine(IrisEngine engine, AtomicInteger scopes) {
@@ -14,7 +14,7 @@ dependencies {
    // log4j-core Filter interface, so its constructor reference needs the type resolvable.
    compileOnly(libs.log4j.core)
    testImplementation('junit:junit:4.13.2')
-    testImplementation('org.mockito:mockito-core:5.23.0')
+    testImplementation(libs.mockito.core)
    testImplementation(libs.paper.api)
    testImplementation(libs.bstats)
    testImplementation(project(':core'))
@@ -18,6 +18,7 @@

 package art.arcane.iris;

+import java.util.concurrent.CompletionStage;
 import art.arcane.volmlib.util.diagnostics.BukkitDebugDump;
 import art.arcane.iris.generation.runtime.IrisEngineEffects;
 import art.arcane.iris.generation.runtime.IrisWorldManager;
@@ -36,6 +37,7 @@ import art.arcane.iris.world.PendingWorldDeleteQueue;
 import art.arcane.iris.world.PendingWorldReplacementManager;
 import art.arcane.iris.world.WorldRefusalReporter;
 import art.arcane.iris.configuration.SettingsHotloadWatch;
+import art.arcane.iris.update.IrisUpdateNotifier;
 import art.arcane.iris.pack.datapack.ServerConfigurator;
 import art.arcane.iris.pack.datapack.DatapackIngestService;
 import art.arcane.iris.pack.datapack.DatapackIngestService.StartupValidationOutcome;
@@ -58,6 +60,7 @@ import art.arcane.iris.integration.MultiverseCoreLink;
 import art.arcane.iris.platform.bukkit.nms.INMS;
 import art.arcane.volmlib.nativelib.terrain.ServerShutdownBoundary;
 import art.arcane.iris.studio.view.BukkitGuiHost;
+import art.arcane.iris.studio.view.GuiHost;
 import art.arcane.iris.studio.view.PregeneratorJob;
 import art.arcane.iris.platform.bukkit.BoardSVC;
 import art.arcane.iris.command.CommandSVC;
@@ -131,8 +134,11 @@ import org.bukkit.command.Command;
 import org.bukkit.command.CommandSender;
 import org.bukkit.entity.Player;
 import org.bukkit.event.Event;
+import org.bukkit.event.EventHandler;
 import org.bukkit.event.HandlerList;
 import org.bukkit.event.Listener;
+import org.bukkit.event.server.PluginDisableEvent;
+import org.bukkit.event.server.PluginEnableEvent;
 import org.bukkit.generator.BiomeProvider;
 import org.bukkit.generator.ChunkGenerator;
 import org.bukkit.plugin.IllegalPluginAccessException;
@@ -204,6 +210,7 @@ public class Iris extends VolmitPlugin implements Listener, ReloadAware {
    private volatile PlaceholderRegistration papiRegistration;
    private volatile IrisPapiListener papiListener;
    private volatile IrisPapiState papiState;
+    private volatile boolean papiLifecycleActive;
    private KMap<Class<? extends IrisService>, IrisService> services;
    // Copy-on-write: mutated on the main thread during enable() and iterated by the JVM
    // shutdown-hook thread during teardown; a plain list would CME and abort the teardown.
@@ -214,9 +221,9 @@ public class Iris extends VolmitPlugin implements Listener, ReloadAware {
    private final PendingWorldDeleteQueue pendingWorldDeletes = new PendingWorldDeleteQueue(this);
    private final PendingWorldReplacementManager pendingWorldReplacements = new PendingWorldReplacementManager(this);
    private BukkitLanguageSwitcher languageSwitcher;
+    private IrisUpdateNotifier updateNotifier;
    private BukkitDebugDump debugDump;
    private volatile SettingsHotloadWatch settingsHotloadWatch;
-    private volatile Thread serverLifecycleThread;
    private volatile ServerShutdownBoundary serverShutdownBoundary;

    public static VolmitSender getSender() {
@@ -636,6 +643,7 @@ public class Iris extends VolmitPlugin implements Listener, ReloadAware {
        languageSwitcher = BukkitLanguageSwitcher.register(this, IrisLanguage.selections(),
                new BukkitLanguageSwitcher.Options("iris", "iris.all",
                        DirectorMiniMenu.Theme.irisGreen(), IrisLanguage.directorResolver(), IrisLanguage.editorOptions()));
+        updateNotifier = new IrisUpdateNotifier(this);
        PaperLibBootstrap.install();
        SimdSupport.install();
        timings.mark("bootstrap");
@@ -824,7 +832,6 @@ public class Iris extends VolmitPlugin implements Listener, ReloadAware {

    public void addShutdownHook() {
        removeShutdownHook();
-        serverLifecycleThread = Thread.currentThread();
        serverShutdownBoundary = INMS.isBound() ? INMS.get().createServerShutdownBoundary() : null;
        shutdownHook = new Thread(this::runShutdownHook, "Iris-ShutdownHook");
        try {
@@ -863,7 +870,14 @@ public class Iris extends VolmitPlugin implements Listener, ReloadAware {
     */
    private CompletableFuture<ManagedWorldLoader.ManagedWorldLoad> loadManagedWorld(String configuredWorldName) {
        return worldReconciler.loadWorld(ServerProperties.BUKKIT_YML, configuredWorldName)
-                .thenApply(result -> new ManagedWorldLoader.ManagedWorldLoad(result.succeeded(), result.message()));
+                .thenApply(this::managedWorldLoadResult);
+    }
+
+    private ManagedWorldLoader.ManagedWorldLoad managedWorldLoadResult(BukkitWorldReconciler.LoadResult result) {
+        if (!result.succeeded() && result.failure() != null) {
+            reportError("Could not explicitly load Iris world " + result.worldKey() + ": " + result.message(), result.failure());
+        }
+        return new ManagedWorldLoader.ManagedWorldLoad(result.succeeded(), result.message());
    }

    public PendingWorldReplacementManager pendingWorldReplacements() {
@@ -927,6 +941,8 @@ public class Iris extends VolmitPlugin implements Listener, ReloadAware {
            ServerConfigurator.restartAtStartupBoundary(restartReason);
            return;
        }
+        papiLifecycleActive = true;
+        setupPapi();
        reportLockedRuntime();
    }

@@ -973,6 +989,14 @@ public class Iris extends VolmitPlugin implements Listener, ReloadAware {
    }

    public void onDisable() {
+        pendingWorldReplacements.awaitStagingForShutdown();
+        GuiHost.shutdown();
+        preservePendingBlockDrops();
+        papiLifecycleActive = false;
+        if (updateNotifier != null) {
+            updateNotifier.close();
+            updateNotifier = null;
+        }
        if (debugDump != null) {
            debugDump.close();
            debugDump = null;
@@ -983,7 +1007,8 @@ public class Iris extends VolmitPlugin implements Listener, ReloadAware {
        }
        IrisLanguage.shutdown();
        teardownPapi();
-        boolean deferToServerStop = FailedEnableLock.defersTeardownToServerStop(enableFailed, IrisToolbelt.isServerStopping());
+        boolean deferToServerStop = FailedEnableLock.defersTeardownToServerStop(enableFailed, IrisToolbelt.isServerStopping())
+                && INMS.get().deferPluginClassLoaderClose();
        boolean restartingAtStartupBoundary = startupBoundaryRestart.get();
        if (restartingAtStartupBoundary) {
            teardownRuntime("startup-boundary-restart", 30L);
@@ -1011,20 +1036,23 @@ public class Iris extends VolmitPlugin implements Listener, ReloadAware {
    }

    @Override
-    public void onPreUnload(ReloadAware.PreUnloadReason reason) {
+    public CompletionStage<Void> commitReload(ReloadAware.PreUnloadReason reason) {
+        preservePendingBlockDrops();
+        papiLifecycleActive = false;
        teardownPapi();
-        if (IrisToolbelt.isServerStopping()) {
+        if (IrisToolbelt.isServerStopping() && INMS.get().deferPluginClassLoaderClose()) {
            quiesceRuntimeForServerShutdown("pre-unload:" + reason);
            startPostStopFinisher();
            Iris.debug("Pre-unload hook deferred generator teardown until Paper closes its chunk schedulers.");
-            return;
+            return CompletableFuture.completedFuture(null);
        }
        if (alreadyDrained.get()) {
            Iris.debug("Pre-unload hook skipped; Iris already drained.");
-            return;
+            return CompletableFuture.completedFuture(null);
        }
        Iris.debug("BileTools pre-unload hook fired (" + reason + "). Freezing all Iris worlds.");
        drainOnce("pre-unload:" + reason, 45L);
+        return CompletableFuture.completedFuture(null);
    }

    /**
@@ -1104,7 +1132,6 @@ public class Iris extends VolmitPlugin implements Listener, ReloadAware {

    private void quiesceRuntimeForServerShutdown(String reason) {
        serverStopTeardownDeferred.set(true);
-        INMS.get().deferPluginClassLoaderClose();
        JigsawStudioService jigsawStudioService = IrisServices.getOrNull(JigsawStudioService.class);
        if (jigsawStudioService != null) {
            try {
@@ -1138,7 +1165,7 @@ public class Iris extends VolmitPlugin implements Listener, ReloadAware {
            if (generator == null) {
                continue;
            }
-            IrisToolbelt.beginWorldMaintenance(world, reason, true);
+            IrisToolbelt.beginWorldMaintenance(world, reason);
            if (!deferredShutdownGenerators.contains(generator)) {
                deferredShutdownGenerators.add(generator);
            }
@@ -1150,52 +1177,32 @@ public class Iris extends VolmitPlugin implements Listener, ReloadAware {
        if (!postStopFinisherStarted.compareAndSet(false, true)) {
            return;
        }
-        Thread activeServerThread = serverLifecycleThread;
-        if (activeServerThread == null) {
-            Iris.warn("Iris could not start its post-stop runtime finisher because the server lifecycle thread is unavailable.");
-            return;
-        }
-
-        Thread finisher = new Thread(() -> {
-            if (!awaitServerThreadTermination(activeServerThread)) {
-                return;
-            }
-            finishDeferredRuntimeTeardown("post-server-stop", 30L);
-        }, "Iris-PostStop-Finisher");
+        Thread finisher = new Thread(() -> finishRuntimeAfterServerShutdown("post-server-stop"),
+                "Iris-PostStop-Finisher");
        finisher.setDaemon(false);
        finisher.start();
    }

-    static boolean awaitServerThreadTermination(Thread serverThread) {
-        if (serverThread == null || serverThread == Thread.currentThread()) {
-            return false;
-        }
-        try {
-            serverThread.join();
-            return true;
-        } catch (InterruptedException e) {
-            Thread.currentThread().interrupt();
-            Iris.reportError("Iris post-stop runtime finisher was interrupted.", e);
-            return false;
-        }
-    }
-
    private void runShutdownHook() {
        if (startupBoundaryRestart.get()) {
            finishDeferredRuntimeTeardown("startup-boundary-restart-hook", 30L);
            return;
        }
+        finishRuntimeAfterServerShutdown("shutdown-hook");
+    }
+
+    private void finishRuntimeAfterServerShutdown(String reason) {
        if (!awaitServerShutdownBoundary()) {
-            SHUTDOWN_ERRORS.println("[Iris] Paper did not reach its post-world-close boundary; retaining the runtime and plugin class loader until JVM exit.");
+            SHUTDOWN_ERRORS.println("[Iris] The server did not reach its post-world-close boundary; retaining the runtime and plugin class loader until JVM exit.");
            return;
        }
-        finishDeferredRuntimeTeardown("shutdown-hook", 30L);
+        finishDeferredRuntimeTeardown(reason, 30L);
    }

    private boolean awaitServerShutdownBoundary() {
        ServerShutdownBoundary boundary = serverShutdownBoundary;
        if (boundary == null) {
-            return true;
+            return false;
        }
        try {
            return boundary.await(
@@ -1259,6 +1266,20 @@ public class Iris extends VolmitPlugin implements Listener, ReloadAware {
                && preservation.hasActiveResources();
    }

+    private void preservePendingBlockDrops() {
+        for (World world : Bukkit.getWorlds()) {
+            PlatformChunkGenerator generator = IrisToolbelt.access(world);
+            if (generator != null && generator.getEngine() != null
+                    && generator.getEngine().getWorldManager() instanceof IrisWorldManager manager) {
+                manager.flushPendingBlockDropsAsync().whenComplete((ignored, failure) -> {
+                    if (failure != null) {
+                        Iris.reportError("Failed to preserve pending block loot before Iris teardown.", failure);
+                    }
+                });
+            }
+        }
+    }
+
    private void drainWorldGenerators(String reason, long timeoutSeconds) {
        List<World> irisWorlds = new ArrayList<>();
        List<PlatformChunkGenerator> generators = new ArrayList<>();
@@ -1313,8 +1334,23 @@ public class Iris extends VolmitPlugin implements Listener, ReloadAware {
        }
    }

-    private void setupPapi() {
-        if (!PlaceholderRegistration.isPlaceholderApiEnabled()) {
+    @EventHandler
+    public void onPlaceholderApiEnable(PluginEnableEvent event) {
+        if ("PlaceholderAPI".equals(event.getPlugin().getName())) {
+            setupPapi();
+        }
+    }
+
+    @EventHandler
+    public void onPlaceholderApiDisable(PluginDisableEvent event) {
+        if ("PlaceholderAPI".equals(event.getPlugin().getName())) {
+            teardownPapi();
+        }
+    }
+
+    private synchronized void setupPapi() {
+        if (!papiLifecycleActive || papiRegistration != null
+                || !PlaceholderRegistration.isPlaceholderApiEnabled()) {
            return;
        }

@@ -1341,7 +1377,7 @@ public class Iris extends VolmitPlugin implements Listener, ReloadAware {
        papiRegistration = registration;
    }

-    private void teardownPapi() {
+    private synchronized void teardownPapi() {
        IrisPapiListener listener = papiListener;
        papiListener = null;

@@ -1453,12 +1489,15 @@ public class Iris extends VolmitPlugin implements Listener, ReloadAware {
    public int getIrisVersion() {
        String input = getDescription().getVersion();
        int hyphenIndex = input.indexOf('-');
-        if (hyphenIndex != -1) {
-            String result = input.substring(0, hyphenIndex);
-            result = result.replaceAll("\\.", "");
-            return Integer.parseInt(result);
+        String release = hyphenIndex < 0 ? input : input.substring(0, hyphenIndex);
+        if (!release.matches("[0-9]+(?:\\.[0-9]+)*")) {
+            return -1;
+        }
+        try {
+            return Integer.parseInt(release.replace(".", ""));
+        } catch (NumberFormatException invalid) {
+            return -1;
        }
-        return -1;
    }

    public int getMCVersion() {
@@ -25,12 +25,13 @@ import art.arcane.iris.localization.IrisLanguage;
 import art.arcane.iris.pack.datapack.DatapackIngestService;
 import art.arcane.iris.studio.object.ObjectStudioSaveService;
 import art.arcane.iris.generation.runtime.Engine;
+import art.arcane.iris.generation.locator.SubterrainLocator;
+import art.arcane.iris.generation.subterrain.IrisSubterrainFamily;
 import art.arcane.iris.structure.placement.IrisStructureLocator;
 import art.arcane.iris.structure.nativegen.NativeStructureGenerationPolicy;
 import art.arcane.iris.structure.placement.StructureReachability;
 import art.arcane.iris.world.history.GenerationSemanticQueries;
-import art.arcane.iris.generation.hydrology.HydrologyFeatureQuery;
-import art.arcane.iris.generation.hydrology.runtime.IrisHydrologyRuntime;
+import art.arcane.iris.generation.hydrology.query.HydrologyFeatureType;
 import art.arcane.iris.generation.biome.IrisBiome;
 import art.arcane.iris.structure.nativegen.IrisNativeStructureDecision;
 import art.arcane.iris.generation.terrain.IrisRegion;
@@ -72,7 +73,7 @@ import java.util.Set;

@Director(name = "find", origin = DirectorOrigin.PLAYER, description = "Iris Find commands", descriptionKey = "iris.director.commandfind.director.iris_find_commands", aliases = "goto")
 public class CommandFind implements DirectorExecutor {
-    @Director(description = "Find a biome", descriptionKey = "iris.director.commandfind.director.find_biome")
+    @Director(description = "Find a biome", sync = true, descriptionKey = "iris.director.commandfind.director.find_biome")
    public void biome(
            @Param(description = "The biome to look for", descriptionKey = "iris.director.commandfind.param.biome_look", customHandler = ReachableBiomeHandler.class)
            IrisBiome biome,
@@ -89,6 +90,78 @@ public class CommandFind implements DirectorExecutor {
        EngineBukkitOps.gotoBiome(e, biome, player(), teleport);
    }

+    @Director(description = "Find an authored underground feature by id or geometry family", sync = true)
+    public void subterrain(
+            @Param(description = "Feature definition id or family: tectonic_fault, cenote, lava_tube, travertine_terraces")
+            String feature,
+            @Param(description = "Search radius in blocks", defaultValue = "8192")
+            int radius,
+            @Param(description = "Should you be teleported", defaultValue = "true")
+            boolean teleport
+    ) {
+        String key = feature.trim();
+        IrisSubterrainFamily family = null;
+        try {
+            family = IrisSubterrainFamily.valueOf(key.toUpperCase(Locale.ROOT).replace('-', '_'));
+        } catch (IllegalArgumentException ignored) {
+        }
+        locateSubterrain(new SubterrainLocator.Query(family == null ? key : "", family, ""), radius, teleport);
+    }
+
+    @Director(name = "underground-biome", description = "Find a bounded authored underground biome", sync = true)
+    public void undergroundBiome(
+            @Param(description = "The underground biome to look for", customHandler = ReachableBiomeHandler.class)
+            IrisBiome biome,
+            @Param(description = "Search radius in blocks", defaultValue = "8192")
+            int radius,
+            @Param(description = "Should you be teleported", defaultValue = "true")
+            boolean teleport
+    ) {
+        locateSubterrain(new SubterrainLocator.Query("", null, biome.getLoadKey()), radius, teleport);
+    }
+
+    private void locateSubterrain(SubterrainLocator.Query query, int radius, boolean teleport) {
+        Engine activeEngine = engine();
+        VolmitSender commandSender = sender();
+        Player target = player();
+        if (activeEngine == null || commandSender == null || target == null) {
+            if (commandSender != null) {
+                commandSender.sendMessage(C.RED + "Run this command from an Iris world.");
+            }
+            return;
+        }
+        if (radius < 0 || radius > 32768) {
+            commandSender.sendMessage(C.RED + "Search radius must be between 0 and 32768 blocks.");
+            return;
+        }
+        Location origin = target.getLocation();
+        World world = origin.getWorld();
+        commandSender.sendMessage(C.GRAY + "Searching authored underground plans...");
+        J.a(() -> {
+            try {
+                SubterrainLocator.Result found = GenerationSemanticQueries.nearestSubterrain(activeEngine, query,
+                        origin.getBlockX(), origin.getBlockY(), origin.getBlockZ(), radius).orElse(null);
+                if (found == null) {
+                    sendStructureMessage(target, commandSender,
+                            C.YELLOW + "No matching authored underground volume found within " + radius + " blocks.");
+                    return;
+                }
+                String label = found.family().name().toLowerCase(Locale.ROOT) + " " + found.featureId();
+                if (!teleport) {
+                    sendStructureMessage(target, commandSender, C.GREEN + "Found " + label + " at "
+                            + found.x() + ", " + found.y() + ", " + found.z() + ".");
+                    return;
+                }
+                prepareStructureTeleport(target, world, commandSender, label,
+                        new Location(world, found.x(), found.y(), found.z()), true);
+            } catch (Throwable error) {
+                sendStructureMessage(target, commandSender,
+                        C.RED + "Could not locate authored underground volume: " + error.getMessage());
+                Iris.reportError("Could not locate authored underground volume.", error);
+            }
+        });
+    }
+
    @Director(description = "Find a region", descriptionKey = "iris.director.commandfind.director.find_region")
    public void region(
            @Param(description = "The region to look for", descriptionKey = "iris.director.commandfind.param.region_look", customHandler = ReachableRegionHandler.class)
@@ -122,9 +195,9 @@ public class CommandFind implements DirectorExecutor {
        EngineBukkitOps.gotoPOI(e, type, player(), teleport);
    }

-    @Director(description = "Find an accepted hydrology feature", sync = true)
+    @Director(description = "Find a hydrology water feature", sync = true)
    public void river(
-            @Param(description = "Feature type: surface, waterfall, underground, grotto, mouth, or a deep-fluid id", customHandler = HydrologyTypeHandler.class)
+            @Param(description = "Feature type: stream, river, major_river, cascade, waterfall, mouth, pond, lake, dam, sea_inlet or cave_pool", customHandler = HydrologyTypeHandler.class)
            String type,
            @Param(description = "Should you be teleported", defaultValue = "true")
            boolean teleport
@@ -138,42 +211,32 @@ public class CommandFind implements DirectorExecutor {
            }
            return;
        }
-        IrisHydrologyRuntime runtime = activeEngine.getComplex().getHydrologyRuntime();
-        HydrologyFeatureQuery query;
+        HydrologyFeatureType featureType;
        try {
-            query = HydrologyFeatureQuery.parse(type);
+            featureType = HydrologyFeatureType.parse(type);
        } catch (IllegalArgumentException error) {
            commandSender.sendMessage(C.RED + error.getMessage());
            return;
        }
+        String label = featureType.key().replace('_', ' ');
        Location origin = target.getLocation();
        World originWorld = origin.getWorld();
-        int requestedDistance = runtime == null
-                ? 8192
-                : Math.min(8192, runtime.settings().routing().tileSize() * 15);
-        int maximumDistance = runtime == null
-                ? requestedDistance
-                : runtime.maximumFeatureSearchDistance(
-                        origin.getBlockX(), origin.getBlockZ(), requestedDistance);
-        commandSender.sendMessage(C.GRAY + "Searching accepted hydrology plans for " + type + "...");
+        int maximumDistance = GenerationSemanticQueries.RIVER_SEARCH_DISTANCE;
+        commandSender.sendMessage(C.GRAY + GenerationSemanticQueries.riverSearchMessage(featureType, maximumDistance));
        J.a(() -> {
            try {
                GenerationSemanticQueries.RiverResult feature = GenerationSemanticQueries.nearestRiver(
                        activeEngine,
-                        query,
+                        featureType,
                        origin.getBlockX(),
                        origin.getBlockZ(),
-                        maximumDistance,
-                        (int visited) -> sendStructureMessage(target, commandSender,
-                                C.GRAY + "Searched " + visited + " hydrology tiles for " + type + "...")
+                        maximumDistance
                ).orElse(null);
                if (feature == null) {
                    sendStructureMessage(target, commandSender,
-                            C.YELLOW + "No accepted " + type + " hydrology feature found within "
-                                    + maximumDistance + " blocks.");
+                            C.YELLOW + GenerationSemanticQueries.riverNotFoundMessage(featureType, maximumDistance));
                    return;
                }
-                String label = type + " hydrology feature";
                if (!teleport) {
                    sendStructureMessage(target, commandSender,
                            C.GREEN + "Found " + label + " at " + feature.x() + ", " + feature.y() + ", " + feature.z() + ".");
@@ -185,8 +248,9 @@ public class CommandFind implements DirectorExecutor {
                        target, originWorld, commandSender, label, destination, true);
            } catch (Throwable error) {
                sendStructureMessage(target, commandSender,
-                        C.RED + "Could not locate " + type + " hydrology: " + error.getClass().getSimpleName());
-                Iris.reportError("Could not locate accepted hydrology feature '" + type + "'.", error);
+                        C.RED + "Could not search for " + label + ": " + error.getClass().getSimpleName()
+                                + (error.getMessage() == null ? "" : " - " + error.getMessage()));
+                Iris.reportError("Could not locate hydrology feature '" + featureType.key() + "'.", error);
            }
        });
    }
@@ -18,6 +18,8 @@

 package art.arcane.iris.command;

+import art.arcane.iris.pack.PackFingerprints;
+
 import art.arcane.iris.Iris;
 import art.arcane.iris.pack.validation.PackCompatReport;
 import art.arcane.iris.pack.PackDirectoryResolver;
@@ -174,7 +176,6 @@ public class CommandPack implements DirectorExecutor {
                s.sendMessage(IrisLanguage.text(BukkitRuntimeMessages.COMMAND_PACK_NO_CLEANUP_CANDIDATES_FOUND_PACK, MessageArgument.untrusted("pack", String.valueOf(pack))));
                return;
            }
-            PackValidationRegistry.remove(packFolder.getName());
            s.sendMessage(IrisLanguage.text(BukkitRuntimeMessages.COMMAND_PACK_QUARANTINED_CLEANUP_CANDIDATE_S_UNDER, MessageArgument.untrusted("size", String.valueOf(result.quarantinedPaths().size())), MessageArgument.untrusted("quarantinePath", String.valueOf(result.quarantinePath()))));
            reportPaths(s, result.quarantinedPaths(), BukkitRuntimeMessages.COMMAND_PACK_PATH_QUARANTINED);
            return;
@@ -230,7 +231,6 @@ public class CommandPack implements DirectorExecutor {
                s.sendMessage(IrisLanguage.text(BukkitRuntimeMessages.COMMAND_PACK_NOTHING_RESTORE_PACK, MessageArgument.untrusted("pack", String.valueOf(pack))));
                return;
            }
-            PackValidationRegistry.remove(packFolder.getName());
            s.sendMessage(IrisLanguage.text(BukkitRuntimeMessages.COMMAND_PACK_RESTORED_FILE_S_FROM, MessageArgument.untrusted("size", String.valueOf(result.restoredPaths().size())), MessageArgument.untrusted("dumpPath", String.valueOf(result.dumpPath()))));
            reportPaths(s, result.restoredPaths(), BukkitRuntimeMessages.COMMAND_PACK_PATH_RESTORED);
            return;
@@ -363,47 +363,79 @@ public class CommandPack implements DirectorExecutor {
        return persisted == null || persisted.isBlank() ? "unknown" : persisted;
    }

-    private PackValidationResult runValidate(VolmitSender s, File packFolder) {
+    PackValidationResult runValidate(VolmitSender s, File packFolder) {
+        PackValidationRegistry.ValidationTicket ticket =
+                PackValidationRegistry.tryBeginValidation(packFolder.toPath());
+        PackValidationResult result;
+        String contentFingerprint = "";
+        String contextFingerprint = "";
        try {
-            PackValidationResult result = PackValidator.validate(packFolder);
-            PackValidationRegistry.publish(result);
-            reportResult(s, result);
-            return result;
+            if (ticket == null) {
+                throw new IllegalStateException("Pack content is currently being changed.");
+            }
+            contentFingerprint = PackFingerprints.computePackTreeFingerprint(packFolder);
+            contextFingerprint = PackValidationCache.contextFingerprint();
+            result = PackValidator.validate(packFolder);
+            if (!contentFingerprint.equals(PackFingerprints.computePackTreeFingerprint(packFolder))
+                    || !contextFingerprint.equals(PackValidationCache.contextFingerprint())) {
+                throw new IllegalStateException("Pack content or validation context changed during validation.");
+            }
        } catch (Throwable e) {
            Iris.reportError("Pack validation failed for '" + packFolder.getName() + "'", e);
            String detail = e.getMessage() == null || e.getMessage().isBlank()
                    ? e.getClass().getSimpleName()
                    : e.getMessage();
-            PackValidationResult result = new PackValidationResult(
+            result = new PackValidationResult(
                    packFolder.getName(),
                    List.of("Pack validation failed with " + e.getClass().getSimpleName() + ": " + detail),
                    List.of(),
                    System.currentTimeMillis());
-            PackValidationRegistry.publish(result);
-            reportResult(s, result);
-            return result;
+            contentFingerprint = "";
+            contextFingerprint = "";
        }
+        if (PackValidationRegistry.publishIfCurrent(ticket, result, contentFingerprint, contextFingerprint)) {
+            PackValidationRegistry.publish(result);
+        } else {
+            result = new PackValidationResult(packFolder.getName(),
+                    List.of("Pack content changed during validation."), List.of(), System.currentTimeMillis());
+        }
+        reportResult(s, result);
+        return result;
    }

    private void persistValidationCache(File packsRoot) {
-        List<File> packDirectories = PackDirectoryResolver.listVisiblePackDirectories(packsRoot);
-        List<PackValidationResult> results = new ArrayList<>(packDirectories.size());
-        for (File packDirectory : packDirectories) {
-            PackValidationResult result = PackValidationRegistry.get(packDirectory.getName());
-            if (result == null) {
-                // The boot cache only loads when it covers every pack, so a partial write is
-                // pointless - but say so instead of silently skipping the persist forever.
-                Iris.warn("Pack validation cache not written: \"" + packDirectory.getName()
-                        + "\" has no registered result. Run /iris pack validate all to repopulate it.");
+        try {
+            String contextFingerprint = PackValidationCache.contextFingerprint();
+            PackFingerprints.PackContentSnapshot snapshot = PackFingerprints.computePackContentSnapshot(packsRoot);
+            List<File> packDirectories = PackDirectoryResolver.listVisiblePackDirectories(packsRoot);
+            List<PackValidationResult> results = new ArrayList<>(packDirectories.size());
+            for (File packDirectory : packDirectories) {
+                PackValidationResult result = PackValidationRegistry.getMatching(
+                        packDirectory.toPath(), snapshot.packContents().get(packDirectory.getName()));
+                if (result == null) {
+                    Iris.warn("Pack validation cache not written: \"" + packDirectory.getName()
+                            + "\" has no validation matching its current content. Run /iris pack validate to refresh it.");
+                    return;
+                }
+                results.add(result);
+            }
+            if (!snapshot.content().equals(PackFingerprints.computePackContentSnapshot(packsRoot).content())
+                    || !contextFingerprint.equals(PackValidationCache.contextFingerprint())) {
+                Iris.warn("Pack validation cache not written because pack content or validation context changed.");
                return;
            }
-            results.add(result);
-        }
-        try {
+            for (int index = 0; index < packDirectories.size(); index++) {
+                File packDirectory = packDirectories.get(index);
+                if (PackValidationRegistry.getMatching(packDirectory.toPath(),
+                        snapshot.packContents().get(packDirectory.getName())) != results.get(index)) {
+                    Iris.warn("Pack validation cache not written because validation changed during persistence.");
+                    return;
+                }
+            }
            PackValidationCache.save(
                    Iris.instance.getDataFile("cache", "pack-validation.json").toPath(),
-                    PackValidationCache.contentFingerprint(packsRoot),
-                    PackValidationCache.contextFingerprint(),
+                    snapshot.content(),
+                    contextFingerprint,
                    results);
        } catch (IOException | RuntimeException e) {
            Iris.reportError("Could not persist refreshed pack-validation results", e);
@@ -21,10 +21,9 @@ package art.arcane.iris.command;
 import art.arcane.iris.Iris;
 import art.arcane.iris.platform.bukkit.BukkitPlatform;
 import art.arcane.iris.configuration.IrisSettings;
+import art.arcane.iris.studio.map.MapWindow;
+import art.arcane.iris.studio.map.PaletteExplorerStart;
 import art.arcane.iris.studio.view.GuiHost;
-import art.arcane.iris.studio.view.ImageMapStudioGUI;
-import art.arcane.iris.studio.view.NoiseExplorerGUI;
-import art.arcane.iris.studio.view.VisionGUI;
 import art.arcane.iris.pack.loading.IrisData;
 import art.arcane.iris.studio.workspace.IrisProject;
 import art.arcane.iris.studio.workspace.IrisCodeWorkspace;
@@ -81,7 +80,6 @@ import org.bukkit.FluidCollisionMode;
 import org.bukkit.Location;
 import org.bukkit.World;
 import org.bukkit.entity.Player;
-import org.bukkit.event.inventory.InventoryType;
 import org.bukkit.inventory.Inventory;
 import org.bukkit.util.Vector;

@@ -99,7 +97,9 @@ import java.util.Objects;
 import java.util.UUID;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicInteger;
+import java.util.function.Consumer;

 import art.arcane.iris.localization.IrisLanguage;
 import art.arcane.iris.localization.BukkitCommandMessages;
@@ -256,15 +256,10 @@ public class CommandStudio implements DirectorExecutor {
            long seed
    ) {
        if (noGUI()) return;
-        sender().sendMessage(IrisLanguage.text(BukkitCommandMessagesExtended.COMMAND_STUDIO_OPENING_NOISE_EXPLORER));
-
-        if (generator == null) {
-            NoiseExplorerGUI.launch();
-            return;
-        }
-
-        String generatorKey = generator.getLoadKey();
-        NoiseExplorerGUI.launchGeneratorKey(generatorKey, generator, seed);
+        VolmitSender commandSender = sender();
+        UUID openerId = commandSender.isPlayer() ? commandSender.player().getUniqueId() : null;
+        MapWindow.NoiseSelection selection = new MapWindow.NoiseSelection(generator == null ? null : generator.getLoadKey(), generator, seed);
+        withPlayerContext(opener -> openNoiseAtPlayer(commandSender, openerId, opener, selection));
    }

    @Director(description = "Open the image-map studio (External GUI)", descriptionKey = "iris.director.commandstudio.director.open_image_map_studio_external_gui", aliases = {"imap"})
@@ -280,8 +275,7 @@ public class CommandStudio implements DirectorExecutor {
            return;
        }

-        Engine activeEngine = IrisToolbelt.access(world).getEngine();
-        ImageMapStudioGUI.launch(activeEngine);
+        requestMapStart(world, MapWindow::openImageMaps);
        sender().sendMessage(IrisLanguage.text(BukkitCommandMessagesExtended.COMMAND_STUDIO_OPENING_IMAGE_MAP_STUDIO));
    }

@@ -309,23 +303,33 @@ public class CommandStudio implements DirectorExecutor {
        O<Integer> ta = new O<>();
        ta.set(-1);

-        var sender = sender();
-        var player = player();
-        var engine = engine();
+        VolmitSender sender = sender();
+        Player player = player();
+        Engine engine = engine();

-        ta.set(J.sr(() ->
-        {
-            if (!player.getOpenInventory().getType().equals(InventoryType.CHEST)) {
+        ta.set(J.sr(() -> {
+            if (!J.runEntity(player, () -> {
+                if (player.getOpenInventory().getTopInventory() != inv) {
+                    J.csr(ta.get());
+                    sender.sendMessage(IrisLanguage.text(BukkitCommandMessages.COMMAND_STUDIO_OPENED_INVENTORY));
+                    return;
+                }
+                if (!add) {
+                    inv.clear();
+                }
+                Location location = player.getLocation();
+                try {
+                    EngineBukkitOps.addItems(engine, true, inv, tables, InventorySlotType.STORAGE,
+                            location.getWorld(), location.getBlockX(), location.getBlockY(), location.getBlockZ());
+                } catch (RuntimeException | Error failure) {
+                    J.csr(ta.get());
+                    Iris.reportError(failure);
+                    sender.sendMessage(IrisLanguage.text(BukkitCommandMessagesExtended.COMMAND_STUDIO_CANNOT_ADD_ITEMS_VIRTUAL_INVENTORY_BECAUSE,
+                            MessageArgument.untrusted("value", String.valueOf(failure.getMessage()))));
+                }
+            }, 0, () -> J.csr(ta.get()))) {
                J.csr(ta.get());
-                sender.sendMessage(IrisLanguage.text(BukkitCommandMessages.COMMAND_STUDIO_OPENED_INVENTORY));
-                return;
            }
-
-            if (!add) {
-                inv.clear();
-            }
-
-            EngineBukkitOps.addItems(engine, true, inv, tables, InventorySlotType.STORAGE, player.getWorld(), player.getLocation().getBlockX(), player.getLocation().getBlockY(), player.getLocation().getBlockZ());
        }, fast ? 5 : 35));

        sender().sendMessage(IrisLanguage.text(BukkitCommandMessagesExtended.COMMAND_STUDIO_OPENING_INVENTORY_NOW));
@@ -411,11 +415,61 @@ public class CommandStudio implements DirectorExecutor {
            return;
        }

-        UUID openerId = sender().isPlayer() ? player().getUniqueId() : null;
-        VisionGUI.launch(IrisToolbelt.access(world).getEngine(), openerId);
+        requestMapStart(world, MapWindow::openMap);
        sender().sendMessage(IrisLanguage.text(BukkitCommandMessagesExtended.COMMAND_STUDIO_OPENING_MAP));
    }

+    // The map opens where the player stands when they are in that world, otherwise at the world origin.
+    private PaletteExplorerStart mapStartIn(World world, Player opener, UUID openerId) {
+        Location center = opener != null && opener.getWorld().equals(world) ? opener.getLocation() : null;
+        return new PaletteExplorerStart(
+                IrisToolbelt.access(world).getEngine(),
+                world.getUID(),
+                openerId,
+                null,
+                center == null ? 0D : center.getX(),
+                center == null ? 0D : center.getZ()
+        );
+    }
+
+    private void requestMapStart(World world, Consumer<PaletteExplorerStart> launch) {
+        UUID openerId = sender().isPlayer() ? player().getUniqueId() : null;
+        withPlayerContext(opener -> launch.accept(mapStartIn(world, opener, openerId)));
+    }
+
+    private void openNoiseAtPlayer(VolmitSender commandSender, UUID openerId, Player opener, MapWindow.NoiseSelection selection) {
+        World world = opener == null ? null : opener.getWorld();
+        PlatformChunkGenerator worldGenerator = world == null ? null : IrisToolbelt.access(world);
+        Engine engine = worldGenerator == null ? GuiHost.get().findActiveEngine() : worldGenerator.getEngine();
+        if (engine == null) {
+            commandSender.sendMessage(IrisLanguage.text(BukkitCommandMessagesExtended.COMMAND_STUDIO_YOU_NEED_BE_SPECIFY_IRIS_GENERATED_WORLD));
+            return;
+        }
+        PaletteExplorerStart start = worldGenerator == null
+                ? new PaletteExplorerStart(engine, null, openerId, null, 0D, 0D)
+                : mapStartIn(world, opener, openerId);
+        MapWindow.openNoise(start, selection);
+        commandSender.sendMessage(IrisLanguage.text(BukkitCommandMessagesExtended.COMMAND_STUDIO_OPENING_NOISE_EXPLORER));
+    }
+
+    private void withPlayerContext(Consumer<Player> action) {
+        Player opener = sender().isPlayer() ? player() : null;
+        if (opener == null) {
+            action.accept(null);
+            return;
+        }
+        AtomicBoolean completed = new AtomicBoolean();
+        Consumer<Player> complete = player -> {
+            if (completed.compareAndSet(false, true)) {
+                action.accept(player);
+            }
+        };
+        Runnable retired = () -> complete.accept(null);
+        if (!J.runEntity(opener, () -> complete.accept(opener.isOnline() ? opener : null), 0, retired)) {
+            retired.run();
+        }
+    }
+
    @Director(description = "Profiles the performance of a dimension", descriptionKey = "iris.director.commandstudio.director.profiles_performance_dimension", origin = DirectorOrigin.PLAYER)
    public void profile(
            @Param(description = "The dimension to profile", descriptionKey = "iris.director.commandstudio.param.dimension_profile", contextual = true, contextualOverride = true, defaultValue = "default", customHandler = DimensionHandler.class)
@@ -0,0 +1,35 @@
+package art.arcane.iris.generation.runtime;
+
+final class GenerationRateWindow {
+    static final long TIMING_IDLE_MILLIS = 10_000L;
+
+    private long lastSampleAtMs;
+    private int lastGeneratedCount;
+    private long lastGenerationAtMs;
+
+    double sampleChunksPerSecond(int generatedCount, long sampledAtMs) {
+        int safeGeneratedCount = Math.max(0, generatedCount);
+        long previousAt = lastSampleAtMs;
+        int previousCount = lastGeneratedCount;
+        lastSampleAtMs = sampledAtMs;
+        lastGeneratedCount = safeGeneratedCount;
+        if (previousAt <= 0L) {
+            if (safeGeneratedCount > 0) {
+                lastGenerationAtMs = sampledAtMs;
+            }
+            return 0D;
+        }
+        if (sampledAtMs <= previousAt) {
+            return 0D;
+        }
+        int generatedDelta = Math.max(0, safeGeneratedCount - previousCount);
+        if (generatedDelta > 0) {
+            lastGenerationAtMs = sampledAtMs;
+        }
+        return generatedDelta * 1000D / (sampledAtMs - previousAt);
+    }
+
+    boolean generationTimingsFresh(long sampledAtMs) {
+        return lastGenerationAtMs > 0L && sampledAtMs - lastGenerationAtMs <= TIMING_IDLE_MILLIS;
+    }
+}
@@ -460,8 +460,12 @@ public final class IrisEngineSVC implements IrisService {
                    continue;
                }

-                double chunksPerSecond = registered.sampleChunksPerSecond(engine.getGenerated(), now);
-                worldSnapshots.add(EngineTelemetrySnapshot.capture(engine, chunksPerSecond, now));
+                double chunksPerSecond = registered.generationRate.sampleChunksPerSecond(engine.getGenerated(), now);
+                worldSnapshots.add(EngineTelemetrySnapshot.capture(
+                        engine,
+                        chunksPerSecond,
+                        registered.generationRate.generationTimingsFresh(now),
+                        now));
                registered.clearMetricsFailure();
            } catch (Throwable exception) {
                if (EngineMaintenance.isMantleClosed(exception)) {
@@ -552,6 +556,7 @@ public final class IrisEngineSVC implements IrisService {
                progress.generated(),
                progress.totalChunks(),
                progress.chunksRemaining(),
+                progress.chunksInFlight(),
                progress.chunksPerSecond(),
                progress.eta(),
                progress.elapsed(),
@@ -612,8 +617,7 @@ public final class IrisEngineSVC implements IrisService {
        private final AtomicReference<CompletableFuture<Void>> activeMaintenance = new AtomicReference<>();
        private volatile ScheduledFuture<?> maintenance;
        private volatile boolean closed;
-        private long lastGeneratedSampleAtMs;
-        private int lastGeneratedCount;
+        private final GenerationRateWindow generationRate = new GenerationRateWindow();

        private Registered(Registration registration, ScheduledThreadPoolExecutor executor) {
            name = registration.name();
@@ -696,19 +700,6 @@ public final class IrisEngineSVC implements IrisService {
            return activeMaintenance.get() != null;
        }

-        private double sampleChunksPerSecond(int generatedCount, long sampledAtMs) {
-            int safeGeneratedCount = Math.max(0, generatedCount);
-            long previousAt = lastGeneratedSampleAtMs;
-            int previousCount = lastGeneratedCount;
-            lastGeneratedSampleAtMs = sampledAtMs;
-            lastGeneratedCount = safeGeneratedCount;
-            if (previousAt <= 0L || sampledAtMs <= previousAt) {
-                return 0D;
-            }
-            int generatedDelta = Math.max(0, safeGeneratedCount - previousCount);
-            return generatedDelta * 1000D / (sampledAtMs - previousAt);
-        }
-
        private void close() {
            if (closed) {
                return;
@@ -101,6 +101,7 @@ public record IrisTelemetrySnapshot(
            long generated,
            long total,
            long remaining,
+            long inFlight,
            double chunksPerSecond,
            long etaMs,
            long elapsedMs,
@@ -115,6 +116,7 @@ public record IrisTelemetrySnapshot(
                0L,
                0L,
                0L,
+                0L,
                0D,
                0L,
                0L,
@@ -130,6 +132,7 @@ public record IrisTelemetrySnapshot(
            generated = Math.max(0L, generated);
            total = Math.max(0L, total);
            remaining = Math.max(0L, remaining);
+            inFlight = Math.max(0L, inFlight);
            chunksPerSecond = Double.isFinite(chunksPerSecond) ? Math.max(0D, chunksPerSecond) : 0D;
            etaMs = Math.max(0L, etaMs);
            elapsedMs = Math.max(0L, elapsedMs);
@@ -6,6 +6,7 @@ import art.arcane.iris.generation.runtime.IrisTelemetrySnapshot;
 import art.arcane.iris.Iris;
 import art.arcane.iris.generation.runtime.EngineTelemetrySnapshot;
 import art.arcane.iris.spi.IrisServices;
+import art.arcane.iris.world.task.J;
 import art.arcane.iris.platform.bukkit.plugin.IrisService;
 import art.arcane.volmlib.integration.IntegrationHandshakeRequest;
 import art.arcane.volmlib.integration.IntegrationHandshakeResponse;
@@ -13,6 +14,9 @@ import art.arcane.volmlib.integration.IntegrationHeartbeat;
 import art.arcane.volmlib.integration.IntegrationMetricDescriptor;
 import art.arcane.volmlib.integration.IntegrationMetricGroup;
 import art.arcane.volmlib.integration.IntegrationMetricSample;
+import art.arcane.volmlib.integration.IntegrationMetricPublisher;
+import art.arcane.volmlib.integration.IntegrationMetricSnapshot;
+import art.arcane.volmlib.integration.IntegrationSnapshotProvider;
 import art.arcane.volmlib.integration.IntegrationMetricSchema;
 import art.arcane.volmlib.integration.IntegrationProtocolNegotiator;
 import art.arcane.volmlib.integration.IntegrationProtocolVersion;
@@ -30,7 +34,7 @@ import java.util.Optional;
 import java.util.Set;
 import java.util.function.Supplier;

-public class IrisIntegrationService implements IrisService, IntegrationServiceContract {
+public class IrisIntegrationService implements IrisService, IntegrationSnapshotProvider {
    private static final IntegrationProtocolVersion CURRENT_PROTOCOL = new IntegrationProtocolVersion(1, 2);
    private static final Set<IntegrationProtocolVersion> SUPPORTED_PROTOCOLS = Set.of(
            new IntegrationProtocolVersion(1, 0),
@@ -41,6 +45,7 @@ public class IrisIntegrationService implements IrisService, IntegrationServiceCo
            "handshake",
            "heartbeat",
            "metrics",
+            IntegrationSnapshotProvider.CAPABILITY,
            "metric-groups",
            "iris-engine-metrics",
            "iris-world-metrics"
@@ -63,6 +68,9 @@ public class IrisIntegrationService implements IrisService, IntegrationServiceCo
    );

    private final Supplier<IrisTelemetrySnapshot> telemetrySupplier;
+    private final IntegrationMetricPublisher snapshots = new IntegrationMetricPublisher(
+            IntegrationMetricSchema.irisKeys().size(), 30_000L);
+    private int snapshotTaskId = -1;

    public IrisIntegrationService() {
        this(IrisIntegrationService::currentTelemetry);
@@ -77,11 +85,17 @@ public class IrisIntegrationService implements IrisService, IntegrationServiceCo
    @Override
    public void onEnable() {
        Bukkit.getServicesManager().register(IntegrationServiceContract.class, this, Iris.instance, ServicePriority.Normal);
+        snapshotTaskId = J.ar(this::publishSnapshots, 20);
        Iris.verbose("Integration provider registered for Iris");
    }

    @Override
    public void onDisable() {
+        if (snapshotTaskId != -1) {
+            J.car(snapshotTaskId);
+            snapshotTaskId = -1;
+        }
+        snapshots.clear();
        Bukkit.getServicesManager().unregister(IntegrationServiceContract.class, this);
    }

@@ -188,6 +202,20 @@ public class IrisIntegrationService implements IrisService, IntegrationServiceCo
        return Map.copyOf(selected);
    }

+    @Override
+    public IntegrationMetricSnapshot snapshotMetrics(Set<String> metricKeys) {
+        return snapshots.snapshotMetrics(metricKeys, System.currentTimeMillis());
+    }
+
+    void publishSnapshots() {
+        IntegrationMetricPublisher.Demand demand = snapshots.demandedKeys(System.currentTimeMillis());
+        if (demand.keys().isEmpty()) {
+            return;
+        }
+        Map<String, IntegrationMetricSample> samples = sampleMetrics(demand.keys());
+        snapshots.publish(demand, System.currentTimeMillis(), samples);
+    }
+
    @Override
    public List<IntegrationMetricGroup> metricGroups() {
        IrisTelemetrySnapshot snapshot = safeSnapshot();
@@ -319,6 +347,7 @@ public class IrisIntegrationService implements IrisService, IntegrationServiceCo
                    IntegrationMetricSchema.IRIS_PREGEN_GENERATED,
                    IntegrationMetricSchema.IRIS_PREGEN_TOTAL,
                    IntegrationMetricSchema.IRIS_PREGEN_QUEUE,
+                    IntegrationMetricSchema.IRIS_PREGEN_REMAINING,
                    IntegrationMetricSchema.IRIS_PREGEN_THROUGHPUT,
                    IntegrationMetricSchema.IRIS_PREGEN_ETA_MS,
                    IntegrationMetricSchema.IRIS_PREGEN_ELAPSED_MS,
@@ -332,7 +361,8 @@ public class IrisIntegrationService implements IrisService, IntegrationServiceCo
        put(samples, IntegrationMetricSchema.IRIS_PREGEN_PROGRESS, pregenerator.progressPercent(), sampledAtMs);
        put(samples, IntegrationMetricSchema.IRIS_PREGEN_GENERATED, pregenerator.generated(), sampledAtMs);
        put(samples, IntegrationMetricSchema.IRIS_PREGEN_TOTAL, pregenerator.total(), sampledAtMs);
-        put(samples, IntegrationMetricSchema.IRIS_PREGEN_QUEUE, pregenerator.remaining(), sampledAtMs);
+        put(samples, IntegrationMetricSchema.IRIS_PREGEN_QUEUE, pregenerator.inFlight(), sampledAtMs);
+        put(samples, IntegrationMetricSchema.IRIS_PREGEN_REMAINING, pregenerator.remaining(), sampledAtMs);
        put(samples, IntegrationMetricSchema.IRIS_PREGEN_THROUGHPUT, pregenerator.chunksPerSecond(), sampledAtMs);
        put(samples, IntegrationMetricSchema.IRIS_PREGEN_ETA_MS, pregenerator.etaMs(), sampledAtMs);
        put(samples, IntegrationMetricSchema.IRIS_PREGEN_ELAPSED_MS, pregenerator.elapsedMs(), sampledAtMs);
@@ -17,8 +17,7 @@ import art.arcane.iris.platform.bukkit.terrain.IrisSampleLimits;
 import art.arcane.iris.platform.bukkit.terrain.IrisSurfaceClassifier;
 import art.arcane.iris.platform.bukkit.terrain.IrisWorldInfoFactory;
 import art.arcane.iris.generation.runtime.Engine;
-import art.arcane.iris.generation.hydrology.HydrologyColumnLayer;
-import art.arcane.iris.generation.hydrology.HydrologyColumnSample;
+import art.arcane.iris.generation.hydrology.raster.WaterRole;
 import art.arcane.iris.generation.terrain.InferredType;
 import art.arcane.iris.generation.biome.IrisBiome;
 import art.arcane.iris.generation.terrain.IrisRegion;
@@ -108,15 +107,15 @@ public class IrisTerrainSVC implements IrisService, IrisTerrainService {

        try {
            int surface = engine.getHeight(blockX, blockZ);
-            HydrologyColumnSample hydrology = hydrologySample(engine, blockX, blockZ);
+            WaterRole role = engine.getComplex().getWaterRoleStream().get(blockX, blockZ);
            int fluid = (int) Math.round(
-                    engine.getComplex().getRiverWaterSurfaceStream().get(blockX, blockZ));
+                    engine.getComplex().getWaterHeadStream().get(blockX, blockZ));
            InferredType inferredType = null;
            if (IrisSurfaceClassifier.requiresSurfaceBiome(surface, fluid)) {
                IrisBiome biome = engine.getSurfaceBiome(blockX, blockZ);
                inferredType = biome == null ? null : biome.getInferredType();
            }
-            return IrisSurfaceClassifier.classify(surface, fluid, inferredType, hydrology);
+            return IrisSurfaceClassifier.classify(surface, fluid, inferredType, role);
        } catch (Throwable error) {
            reportQueryFault("surfaceKind", world, error);
            return IrisSurfaceKind.UNKNOWN;
@@ -266,12 +265,12 @@ public class IrisTerrainSVC implements IrisService, IrisTerrainService {
                    return false;
                }

-                HydrologyColumnSample hydrology = wantRiver
-                        ? hydrologySample(engine, blockX, blockZ)
-                        : null;
+                WaterRole role = wantRiver
+                        ? engine.getComplex().getWaterRoleStream().get(blockX, blockZ)
+                        : WaterRole.NONE;
                int surface = wantHeight || wantKind ? engine.getHeight(blockX, blockZ) : 0;
                int fluid = wantRiver
-                        ? (int) Math.round(engine.getComplex().getRiverWaterSurfaceStream().get(blockX, blockZ))
+                        ? (int) Math.round(engine.getComplex().getWaterHeadStream().get(blockX, blockZ))
                        : engine.getDimension().getFluidHeight();
                boolean needsBiome = wantBiome
                        || (wantKind && IrisSurfaceClassifier.requiresSurfaceBiome(surface, fluid));
@@ -281,29 +280,23 @@ public class IrisTerrainSVC implements IrisService, IrisTerrainService {
                                surface,
                                fluid,
                                biome == null ? null : biome.getInferredType(),
-                                hydrology
+                                role
                        )
                        : IrisSurfaceKind.UNKNOWN;
                String biomeKey = wantBiome && biome != null ? biome.getLoadKey() : null;
                int natural = wantNaturalHeight
                        ? (int) Math.round(engine.getComplex().getNaturalHeightStream().get(blockX, blockZ)) + minHeight
                        : IrisColumnSample.UNAVAILABLE_HEIGHT;
-                HydrologyColumnLayer surfaceLayer = hydrology == null
-                        ? null
-                        : hydrology.primarySurfaceLayer().orElse(null);
-                boolean riverPresent = surfaceLayer != null;
                IrisRiverState riverState = wantRiverState
-                        ? riverState(hydrology)
+                        ? riverState(role)
                        : IrisRiverState.NONE;
-                double riverDistance = wantRiverDistance && riverPresent
-                        ? engine.getComplex().getRiverDistanceStream().get(blockX, blockZ)
+                double riverDistance = wantRiverDistance
+                        ? riverDistance(role)
                        : IrisColumnSample.UNAVAILABLE_RIVER_DISTANCE;
-                int riverFlow = wantRiverFlow && riverPresent
-                        ? (int) Math.round(engine.getComplex().getRiverFlowStream().get(blockX, blockZ))
+                int riverFlow = wantRiverFlow
+                        ? riverFlow(role)
                        : IrisColumnSample.UNAVAILABLE_RIVER_FLOW;
-                int riverWaterSurfaceY = wantRiverWaterSurface
-                        && surfaceLayer != null
-                        && surfaceLayer.connectedFluid()
+                int riverWaterSurfaceY = wantRiverWaterSurface && role.wet()
                        ? fluid + minHeight
                        : IrisColumnSample.UNAVAILABLE_HEIGHT;
                sink.accept(new IrisColumnSample(
@@ -327,21 +320,25 @@ public class IrisTerrainSVC implements IrisService, IrisTerrainService {
        }
    }

-    static IrisRiverState riverState(HydrologyColumnSample hydrology) {
-        HydrologyColumnLayer layer = hydrology == null
-                ? null
-                : hydrology.primarySurfaceLayer().orElse(null);
-        if (layer == null || !layer.channel()) {
-            return IrisRiverState.NONE;
-        }
-        return layer.connectedFluid() ? IrisRiverState.WET : IrisRiverState.DRY;
+    static IrisRiverState riverState(WaterRole role) {
+        return role.wet() ? IrisRiverState.WET : IrisRiverState.NONE;
    }

-    private static HydrologyColumnSample hydrologySample(Engine engine, int blockX, int blockZ) {
-        if (engine.getComplex().getHydrologyRuntime() == null) {
-            return null;
-        }
-        return engine.getComplex().getHydrologyRuntime().sample(blockX, blockZ).orElse(null);
+    static double riverDistance(WaterRole role) {
+        return switch (role) {
+            case NONE -> IrisColumnSample.UNAVAILABLE_RIVER_DISTANCE;
+            case CHANNEL, POND, MOUTH, CASCADE, WATERFALL, INLET -> 0D;
+            case SHORE, POND_SHORE -> 1D;
+            case BANK, DAM -> 2D;
+        };
+    }
+
+    static int riverFlow(WaterRole role) {
+        return switch (role) {
+            case NONE, SHORE, POND_SHORE, BANK, DAM -> IrisColumnSample.UNAVAILABLE_RIVER_FLOW;
+            case CHANNEL, MOUTH, CASCADE, WATERFALL -> 1;
+            case POND, INLET -> 0;
+        };
    }

    private static Optional<String> key(IrisBiome biome) {
@@ -1,8 +1,7 @@
 package art.arcane.iris.platform.bukkit.terrain;

 import art.arcane.iris.api.terrain.IrisSurfaceKind;
-import art.arcane.iris.generation.hydrology.HydrologyColumnLayer;
-import art.arcane.iris.generation.hydrology.HydrologyColumnSample;
+import art.arcane.iris.generation.hydrology.raster.WaterRole;
 import art.arcane.iris.generation.terrain.InferredType;

 public final class IrisSurfaceClassifier {
@@ -29,25 +28,16 @@ public final class IrisSurfaceClassifier {
            int engineSurfaceHeight,
            int engineFluidHeight,
            InferredType inferredType,
-            HydrologyColumnSample hydrology
+            WaterRole role
    ) {
        if (engineSurfaceHeight <= 0) {
            return IrisSurfaceKind.VOID;
        }
-        HydrologyColumnLayer layer = hydrology == null
-                ? null
-                : hydrology.primarySurfaceLayer().orElse(null);
-        if (layer != null) {
-            if (layer.shore()) {
-                return IrisSurfaceKind.RIVER_SHORE;
-            }
-            if (layer.channel()) {
-                return layer.connectedFluid() ? IrisSurfaceKind.RIVER : IrisSurfaceKind.DRY_CHANNEL;
-            }
-            if (layer.grading()) {
-                return IrisSurfaceKind.LAND;
-            }
-        }
-        return classify(engineSurfaceHeight, engineFluidHeight, inferredType);
+        return switch (role) {
+            case NONE -> classify(engineSurfaceHeight, engineFluidHeight, inferredType);
+            case SHORE, POND_SHORE -> IrisSurfaceKind.RIVER_SHORE;
+            case BANK, DAM -> IrisSurfaceKind.LAND;
+            case CHANNEL, POND, MOUTH, CASCADE, WATERFALL, INLET -> IrisSurfaceKind.RIVER;
+        };
    }
 }
@@ -23,6 +23,8 @@ import art.arcane.iris.world.event.IrisEngineHotloadEvent;
 import art.arcane.iris.world.IrisToolbelt;
 import art.arcane.iris.generation.runtime.Engine;
 import art.arcane.iris.platform.generation.PlatformChunkGenerator;
+import art.arcane.iris.studio.StudioSVC;
+import art.arcane.iris.studio.workspace.IrisProject;
 import org.bukkit.Bukkit;
 import org.bukkit.World;
 import org.bukkit.event.EventHandler;
@@ -40,16 +42,21 @@ public final class BukkitGuiHost implements GuiHost.Provider {
        GuiHost.set(new BukkitGuiHost());
    }

+    /**
+     * The engine of the open studio project, which reads the pack folder being edited, or else the first
+     * Iris world. A normal Iris world runs on its own copy of the pack, made when the world was created.
+     */
    @Override
    public Engine findActiveEngine() {
+        Engine studioEngine = findStudioEngine();
+        if (studioEngine != null) {
+            return studioEngine;
+        }
        try {
            for (World world : new ArrayList<>(Bukkit.getWorlds())) {
-                try {
-                    PlatformChunkGenerator access = IrisToolbelt.access(world);
-                    if (access != null && access.getEngine() != null && !access.getEngine().isClosed()) {
-                        return access.getEngine();
-                    }
-                } catch (Throwable ignored) {
+                Engine engine = engineOf(world);
+                if (engine != null) {
+                    return engine;
                }
            }
        } catch (Throwable ignored) {
@@ -57,6 +64,35 @@ public final class BukkitGuiHost implements GuiHost.Provider {
        return null;
    }

+    @Override
+    public Engine findEngine(UUID worldId) {
+        World world = worldId == null ? null : Bukkit.getWorld(worldId);
+        return world == null ? null : engineOf(world);
+    }
+
+    private static Engine findStudioEngine() {
+        try {
+            StudioSVC studio = Iris.service(StudioSVC.class);
+            IrisProject project = studio == null || !studio.isProjectOpen() ? null : studio.getActiveProject();
+            PlatformChunkGenerator provider = project == null ? null : project.getActiveProvider();
+            Engine engine = provider == null ? null : provider.getEngine();
+            return engine == null || engine.isClosed() ? null : engine;
+        } catch (Throwable ignored) {
+            return null;
+        }
+    }
+
+    private static Engine engineOf(World world) {
+        try {
+            PlatformChunkGenerator access = IrisToolbelt.access(world);
+            if (access != null && access.getEngine() != null && !access.getEngine().isClosed()) {
+                return access.getEngine();
+            }
+        } catch (Throwable ignored) {
+        }
+        return null;
+    }
+
    @Override
    public void registerHotloadHook(Runnable onHotload) {
        Listener listener = new HotloadListener(onHotload);
@@ -18,23 +18,19 @@

 package art.arcane.iris.studio.view;

-import art.arcane.volmlib.nativelib.view.WorldMarker;
-
-import art.arcane.iris.generation.runtime.IrisComplex;
 import art.arcane.iris.generation.runtime.Engine;
-import art.arcane.iris.studio.render.RenderType;
 import art.arcane.iris.world.IrisWorld;
 import art.arcane.iris.platform.bukkit.BukkitPlatform;
 import art.arcane.iris.platform.bukkit.BukkitWorldBinding;
 import art.arcane.iris.spi.IrisLogging;
 import art.arcane.iris.world.task.J;
 import art.arcane.volmlib.util.format.Form;
+import org.bukkit.Bukkit;
 import org.bukkit.Location;
 import org.bukkit.World;
 import org.bukkit.entity.LivingEntity;
 import org.bukkit.entity.Player;

-import java.io.File;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
@@ -56,7 +52,7 @@ public final class BukkitVisionOverlay implements GuiOverlay {
    private final AtomicBoolean playerRefreshQueued = new AtomicBoolean();
    private final AtomicLong teleportSequence = new AtomicLong();
    private final AtomicReference<VisionTeleportRequest> latestTeleport = new AtomicReference<>();
-    private volatile List<WorldMarker> playerMarkers = List.of();
+    private volatile List<GuiMarker> playerMarkers = List.of();

    public BukkitVisionOverlay(Engine engine, UUID openerId) {
        this.engine = engine;
@@ -68,7 +64,7 @@ public final class BukkitVisionOverlay implements GuiOverlay {
     * built by a server thread.
     */
    @Override
-    public List<WorldMarker> players() {
+    public List<GuiMarker> players() {
        queuePlayerRefresh();
        return playerMarkers;
    }
@@ -78,26 +74,48 @@ public final class BukkitVisionOverlay implements GuiOverlay {
            return;
        }

-        boolean scheduled = J.runGlobal(() -> {
-            try {
-                List<WorldMarker> markers = new ArrayList<>();
-                for (Player player : BukkitWorldBinding.players(engine.getWorld())) {
-                    Location at = player.getLocation();
-                    markers.add(WorldMarker.player(player.getName(), at.getX(), at.getZ()));
-                }
-                playerMarkers = List.copyOf(markers);
-            } finally {
-                playerRefreshQueued.set(false);
-            }
-        });
+        boolean scheduled = J.runGlobal(this::refreshPlayers);

        if (!scheduled) {
            playerRefreshQueued.set(false);
        }
    }

+    private void refreshPlayers() {
+        World world = BukkitWorldBinding.world(engine.getWorld());
+        List<Player> players = BukkitWorldBinding.players(engine.getWorld());
+        if (players.isEmpty() || world == null) {
+            playerMarkers = List.of();
+            playerRefreshQueued.set(false);
+            return;
+        }
+        List<GuiMarker> markers = Collections.synchronizedList(new ArrayList<>(players.size()));
+        AtomicInteger pending = new AtomicInteger(players.size());
+        for (Player player : players) {
+            AtomicBoolean completed = new AtomicBoolean();
+            Runnable complete = () -> {
+                if (completed.compareAndSet(false, true) && pending.decrementAndGet() == 0) {
+                    playerMarkers = List.copyOf(markers);
+                    playerRefreshQueued.set(false);
+                }
+            };
+            if (!J.runEntity(player, () -> {
+                try {
+                    if (player.isOnline() && player.getWorld() == world) {
+                        Location at = player.getLocation();
+                        markers.add(GuiMarker.player(player.getName(), at.getX(), at.getZ(), at.getYaw()));
+                    }
+                } finally {
+                    complete.run();
+                }
+            }, 0, complete)) {
+                complete.run();
+            }
+        }
+    }
+
    @Override
-    public void requestEntities(Consumer<List<WorldMarker>> sink) {
+    public void requestEntities(Consumer<List<GuiMarker>> sink) {
        J.runGlobal(() -> {
            IrisWorld target = engine.getWorld();
            World world = BukkitWorldBinding.world(target);
@@ -118,7 +136,7 @@ public final class BukkitVisionOverlay implements GuiOverlay {
                return;
            }

-            List<WorldMarker> collected = Collections.synchronizedList(new ArrayList<>(living.size()));
+            List<GuiMarker> collected = Collections.synchronizedList(new ArrayList<>(living.size()));
            AtomicInteger pending = new AtomicInteger(living.size());
            Runnable complete = () -> {
                if (pending.decrementAndGet() == 0) {
@@ -144,22 +162,22 @@ public final class BukkitVisionOverlay implements GuiOverlay {
        });
    }

-    private WorldMarker marker(LivingEntity entity, Location at) {
+    private GuiMarker marker(LivingEntity entity, Location at) {
        String label = Form.capitalizeWords(entity.getType().name().toLowerCase(Locale.ROOT).replaceAll("\\Q_\\E", " "));
        double maxHealth = 0;
        try {
            maxHealth = entity.getAttribute(MAX_HEALTH).getValue();
        } catch (Throwable ignored) {
        }
-        return WorldMarker.entity(label, at.getX(), at.getY(), at.getZ(), entity.getHealth(), maxHealth);
+        return GuiMarker.entity(label, at.getX(), at.getY(), at.getZ(), entity.getHealth(), maxHealth);
    }

    @Override
    public void teleport(double worldX, double worldZ) {
        VisionTeleportRequest request = new VisionTeleportRequest(
                teleportSequence.incrementAndGet(),
-                VisionGUI.floorWorldCoordinate(worldX),
-                VisionGUI.floorWorldCoordinate(worldZ));
+                (int) StrictMath.floor(worldX),
+                (int) StrictMath.floor(worldZ));
        latestTeleport.set(request);
        startTeleport(request);
    }
@@ -212,6 +230,46 @@ public final class BukkitVisionOverlay implements GuiOverlay {
        }
    }

+    @Override
+    public void requestOpenerPosition(Consumer<OpenerPosition> sink) {
+        AtomicBoolean completed = new AtomicBoolean();
+        Consumer<OpenerPosition> complete = position -> {
+            if (completed.compareAndSet(false, true)) {
+                sink.accept(position);
+            }
+        };
+        if (openerId == null) {
+            complete.accept(OpenerPosition.OFFLINE);
+            return;
+        }
+        boolean scheduled = J.runGlobal(() -> {
+            Player player = Bukkit.getPlayer(openerId);
+            if (player == null) {
+                complete.accept(OpenerPosition.OFFLINE);
+                return;
+            }
+            Runnable retired = () -> complete.accept(OpenerPosition.OFFLINE);
+            if (!J.runEntity(player, () -> complete.accept(positionOf(player,
+                    BukkitWorldBinding.world(engine.getWorld()))), 0, retired)) {
+                retired.run();
+            }
+        });
+        if (!scheduled) {
+            complete.accept(OpenerPosition.OFFLINE);
+        }
+    }
+
+    private static OpenerPosition positionOf(Player player, World world) {
+        if (!player.isOnline()) {
+            return OpenerPosition.OFFLINE;
+        }
+        if (world == null || player.getWorld() != world) {
+            return OpenerPosition.IN_OTHER_WORLD;
+        }
+        Location at = player.getLocation();
+        return OpenerPosition.inWorld(at.getX(), at.getY(), at.getZ());
+    }
+
    private Player selectPlayer(List<Player> players) {
        if (openerId == null) {
            return players.isEmpty() ? null : players.get(0);
@@ -316,21 +374,6 @@ public final class BukkitVisionOverlay implements GuiOverlay {
                + blockX + "," + blockZ + ".", failure);
    }

-    @Override
-    public String openInEditor(double worldX, double worldZ, RenderType type) {
-        IrisComplex complex = engine.getComplex();
-        File file = switch (type) {
-            case BIOME, LAYER_LOAD, DECORATOR_LOAD, OBJECT_LOAD, HEIGHT, RIVER ->
-                    complex.getTrueBiomeStream().get(worldX, worldZ).openInVSCode();
-            case BIOME_LAND -> complex.getLandBiomeStream().get(worldX, worldZ).openInVSCode();
-            case BIOME_SEA -> complex.getSeaBiomeStream().get(worldX, worldZ).openInVSCode();
-            case REGION -> complex.getRegionStream().get(worldX, worldZ).openInVSCode();
-            case CAVE_LAND -> complex.getCaveBiomeStream().get(worldX, worldZ).openInVSCode();
-            default -> null;
-        };
-        return file == null ? null : file.getName();
-    }
-
    private static final class VisionTeleportRequest {
        private final long sequence;
        private final int blockX;
@@ -0,0 +1,37 @@
+package art.arcane.iris.update;
+
+import art.arcane.iris.configuration.IrisSettings;
+import art.arcane.volmlib.util.update.BukkitUpdateService;
+import org.bukkit.plugin.Plugin;
+
+import java.util.function.Consumer;
+
+public final class IrisUpdateNotifier implements AutoCloseable {
+    private final Consumer<IrisSettings> settingsListener = this::reconfigure;
+    private final BukkitUpdateService updates;
+    private volatile boolean enabled;
+    private boolean closed;
+
+    public IrisUpdateNotifier(Plugin plugin) {
+        enabled = IrisSettings.get().getGeneral().isUpdateNotifications();
+        updates = BukkitUpdateService.register(plugin, new BukkitUpdateService.Options(
+                "VolmitSoftware", "Iris", "iris.update", () -> enabled));
+        IrisSettings.addSettingsListener(settingsListener);
+        reconfigure(IrisSettings.get());
+    }
+
+    private synchronized void reconfigure(IrisSettings settings) {
+        if (closed) {
+            return;
+        }
+        enabled = settings.getGeneral().isUpdateNotifications();
+        updates.reconfigure();
+    }
+
+    @Override
+    public synchronized void close() {
+        closed = true;
+        IrisSettings.removeSettingsListener(settingsListener);
+        updates.close();
+    }
+}
@@ -18,8 +18,9 @@

 package art.arcane.iris.world;

+import art.arcane.iris.pack.PackFingerprints;
+
 import art.arcane.iris.configuration.IrisSettings;
-import art.arcane.iris.pack.datapack.ServerConfigurator;

 import art.arcane.iris.Iris;
 import art.arcane.iris.world.lifecycle.WorldLifecycleStaging;
@@ -184,12 +185,12 @@ public final class IrisWorldGeneratorResolver {
        }
        List<String> packNames = packDirs.stream().map(File::getName).sorted().toList();
        Path cacheFile = IrisPlatforms.get().dataFile("cache", "pack-validation.json").toPath();
-        ServerConfigurator.PackContentSnapshot contentSnapshot =
-                new ServerConfigurator.PackContentSnapshot("", Map.of());
+        PackFingerprints.PackContentSnapshot contentSnapshot =
+                new PackFingerprints.PackContentSnapshot("", Map.of());
        String contextFingerprint = "";
        Optional<List<PackValidationResult>> cached = Optional.empty();
        try {
-            contentSnapshot = ServerConfigurator.computePackContentSnapshot(packsRoot);
+            contentSnapshot = PackFingerprints.computePackContentSnapshot(packsRoot);
            contextFingerprint = PackValidationCache.contextFingerprint();
            if (!externalContentChanged) {
                cached = PackValidationCache.load(
@@ -274,19 +275,19 @@ public final class IrisWorldGeneratorResolver {
    private static FreshValidation validateStablePacks(
            File packsRoot,
            List<File> initialPackDirs,
-            ServerConfigurator.PackContentSnapshot initialSnapshot
+            PackFingerprints.PackContentSnapshot initialSnapshot
    ) {
        List<File> packDirs = initialPackDirs;
-        ServerConfigurator.PackContentSnapshot before = initialSnapshot;
+        PackFingerprints.PackContentSnapshot before = initialSnapshot;
        for (int attempt = 0; attempt < VALIDATION_STABILITY_ATTEMPTS; attempt++) {
            List<String> packNames = packDirs.stream().map(File::getName).sorted().toList();
            List<PackValidationResult> results = validatePacks(packDirs);
-            ServerConfigurator.PackContentSnapshot after;
+            PackFingerprints.PackContentSnapshot after;
            try {
-                after = ServerConfigurator.computePackContentSnapshot(packsRoot);
+                after = PackFingerprints.computePackContentSnapshot(packsRoot);
            } catch (RuntimeException exception) {
                Iris.reportError("Could not verify Iris pack bytes after validation", exception);
-                after = new ServerConfigurator.PackContentSnapshot("", Map.of());
+                after = new PackFingerprints.PackContentSnapshot("", Map.of());
            }
            List<File> afterPackDirs = PackDirectoryResolver.listVisiblePackDirectories(packsRoot);
            List<String> afterPackNames = afterPackDirs.stream().map(File::getName).sorted().toList();
@@ -895,14 +896,10 @@ public final class IrisWorldGeneratorResolver {
    }

    private static String dimensionTypeKey(IrisData data, IrisDimension dimension) {
-        return IrisPlatforms.get()
-                .registries()
-                .generationRegistry()
-                .dimensionTypeResourceKey(
-                        data.getDataFolder().getName(),
-                        dimension.getLoadKey(),
-                        dimension.getDimensionTypeKey()
-                );
+        return dimension.dimensionTypeResourceKey(
+                IrisPlatforms.get().registries().generationRegistry(),
+                data.getDataFolder().getName()
+        );
    }

    private record LoadedHistory(GenerationHistory history, File activePack) {
@@ -923,7 +920,7 @@ public final class IrisWorldGeneratorResolver {

    private record FreshValidation(
            List<File> packDirs,
-            ServerConfigurator.PackContentSnapshot contentSnapshot,
+            PackFingerprints.PackContentSnapshot contentSnapshot,
            List<PackValidationResult> results,
            boolean stable
    ) {
@@ -58,6 +58,7 @@ import java.util.Set;
 import java.util.UUID;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.TimeoutException;
@@ -78,6 +79,9 @@ public final class PendingWorldReplacementManager implements Listener {
    private volatile UUID overworldEntryAwaitingVerification;
    private volatile World overworldEntryWorld;
    private volatile boolean paperEntryListenerRegistered;
+    private final Object stagingMonitor = new Object();
+    private boolean stagingAdmissionOpen = true;
+    private StagingAdmission activeStaging;

    public PendingWorldReplacementManager(Iris plugin) {
        this.plugin = Objects.requireNonNull(plugin, "plugin");
@@ -135,7 +139,8 @@ public final class PendingWorldReplacementManager implements Listener {
                LifecycleOperationCoordinator.Domain.WORLD_MUTATION,
                LifecycleOperationCoordinator.OperationKind.WORLD_REPLACE,
                requiredWorldKey.toString()
-        ); WorldReplacementProgress progress = WorldReplacementProgress.start(
+        ); StagingAdmission ignoredAdmission = admitStaging(requiredWorldKey);
+             WorldReplacementProgress progress = WorldReplacementProgress.start(
                requiredSender, requiredWorldKey.toString())) {
            synchronized (this) {
                IrisStartupValidation.requireWorldReplacementStagingReady();
@@ -271,6 +276,29 @@ public final class PendingWorldReplacementManager implements Listener {
        }
    }

+    public void awaitStagingForShutdown() {
+        StagingAdmission staging;
+        synchronized (stagingMonitor) {
+            stagingAdmissionOpen = false;
+            staging = activeStaging;
+        }
+        if (staging == null) {
+            return;
+        }
+        Iris.warn("Waiting for the replacement of " + staging.worldKey + " to finish staging before Iris shuts down.");
+        boolean interrupted = false;
+        while (staging.finished.getCount() > 0L) {
+            try {
+                staging.finished.await();
+            } catch (InterruptedException e) {
+                interrupted = true;
+            }
+        }
+        if (interrupted) {
+            Thread.currentThread().interrupt();
+        }
+    }
+
    public synchronized void processPendingStartupReplacements() {
        ArrayList<String> failures = new ArrayList<>();
        ArrayList<String> restartBoundaries = new ArrayList<>();
@@ -1048,6 +1076,17 @@ public final class PendingWorldReplacementManager implements Listener {
        return plugin.getDataFolder().toPath().toAbsolutePath().normalize();
    }

+    private StagingAdmission admitStaging(NamespacedKey worldKey) throws IOException {
+        synchronized (stagingMonitor) {
+            if (!stagingAdmissionOpen) {
+                throw new IOException("Iris is shutting down. Run the replacement again after the server starts.");
+            }
+            StagingAdmission staging = new StagingAdmission(worldKey);
+            activeStaging = staging;
+            return staging;
+        }
+    }
+
    private synchronized void loadOverworldEntryGuard() throws IOException {
        ExactWorldSlotPathPolicy.Target target = resolveTarget(OVERWORLD_KEY);
        Optional<WorldReplacementEntryGuard.Entry> loaded = WorldReplacementEntryGuard.load(target.worldDirectory());
@@ -1218,6 +1257,25 @@ public final class PendingWorldReplacementManager implements Listener {
    record SavedLocationInspection(boolean safe, Throwable failure) {
    }

+    private final class StagingAdmission implements AutoCloseable {
+        private final NamespacedKey worldKey;
+        private final CountDownLatch finished = new CountDownLatch(1);
+
+        private StagingAdmission(NamespacedKey worldKey) {
+            this.worldKey = worldKey;
+        }
+
+        @Override
+        public void close() {
+            synchronized (stagingMonitor) {
+                if (activeStaging == this) {
+                    activeStaging = null;
+                }
+            }
+            finished.countDown();
+        }
+    }
+
    private static final class RestartBoundaryRequired extends IOException {
        private RestartBoundaryRequired(String message) {
            super(message);
@@ -19,6 +19,10 @@
 package art.arcane.iris.world.runtime;

 import art.arcane.iris.api.world.IrisWorldPhase;
+import art.arcane.iris.generation.mantle.CustomBlockOwnership;
+import art.arcane.iris.integration.ExternalDataSVC;
+import art.arcane.iris.spi.IrisServices;
+import art.arcane.volmlib.nativelib.terrain.NativeBlockPoint;
 import art.arcane.iris.pack.datapack.ServerConfigurator;
 import art.arcane.iris.pack.datapack.DatapackIngestService;
 import art.arcane.iris.world.event.IrisEngineHotloadEvent;
@@ -51,6 +55,13 @@ import org.bukkit.World;
 import org.bukkit.WorldBorder;

 public final class BukkitEnginePlatformHooks implements EnginePlatformHooks {
+    @Override
+    public boolean removeCustomBlock(Engine engine, NativeBlockPoint position, CustomBlockOwnership.Entry entry) {
+        ExternalDataSVC service = IrisServices.getOrNull(ExternalDataSVC.class);
+        return service != null && service.removeGenerated(
+                BukkitWorldBinding.world(engine.getWorld()).getBlockAt(position.x(), position.y(), position.z()), entry);
+    }
+
    @Override
    public CompletableFuture<Void> flushSavedTerrainCapture(Engine engine) {
        return INMS.get().flushSavedTerrainCapture(BukkitWorldBinding.world(engine.getWorld()));
@@ -3,19 +3,33 @@ package art.arcane.iris.world.tree;
 import org.bukkit.block.Block;
 import org.bukkit.entity.Player;
 import org.bukkit.event.block.BlockBreakEvent;
+import org.bukkit.inventory.ItemStack;
+
+import java.util.Collection;
+import java.util.Objects;

 final class RoutedBlockBreakEvent extends BlockBreakEvent implements BlockDropRouter {
    private final TreeFellerSVC service;
    private final FellingRun run;
+    private final ItemStack tool;

-    RoutedBlockBreakEvent(Block block, Player player, FellingRun run, TreeFellerSVC service) {
-        super(block, player);
-        this.run = run;
-        this.service = service;
+    RoutedBlockBreakEvent(Options options) {
+        super(options.block(), options.player());
+        run = options.run();
+        service = options.service();
+        tool = Objects.requireNonNull(options.tool(), "tool").clone();
+    }
+
+    @Override
+    public Collection<ItemStack> captureNativeDrops() {
+        return getBlock().getDrops(tool);
    }

    @Override
    public boolean routeDrop(Object drop) {
        return service.isServiceEnabled() && run.presentation.routeDrop(drop);
    }
+
+    record Options(Block block, Player player, FellingRun run, TreeFellerSVC service, ItemStack tool) {
+    }
 }
@@ -387,7 +387,8 @@ final class TreeFellingRunner {
            return;
        }

-        BlockBreakEvent probe = new RoutedBlockBreakEvent(block, run.candidate.player(), run, service);
+        BlockBreakEvent probe = new RoutedBlockBreakEvent(new RoutedBlockBreakEvent.Options(
+                block, run.candidate.player(), run, service, reservation.toolForDrops()));
        service.managedEvents.add(probe);
        try {
            Bukkit.getPluginManager().callEvent(probe);
@@ -10,6 +10,9 @@ authors: [ cyberpwn, NextdoorPsycho, Vatuu ]
 website: VolmitSoftware.com
 description: More than a Dimension!
 permissions:
+  iris.update:
+    description: Allows viewing Iris updates in VolmLib's combined update reports.
+    default: op
  iris.debugdump:
    description: Allows creating and optionally uploading diagnostic reports.
    default: op
@@ -25,34 +28,26 @@ permissions:
 dependencies:
  server:
    PlaceholderAPI:
-      load: BEFORE
+      load: OMIT
      required: false
      join-classpath: true
    CraftEngine:
-      load: BEFORE
+      load: OMIT
      required: false
      join-classpath: true
    Nexo:
-      load: BEFORE
+      load: OMIT
      required: false
      join-classpath: true
    Oraxen:
-      load: BEFORE
+      load: OMIT
      required: false
      join-classpath: true
    ItemsAdder:
-      load: BEFORE
+      load: OMIT
      required: false
      join-classpath: true
    SCore:
-      load: BEFORE
-      required: false
-      join-classpath: true
-    ExecutableItems:
-      load: BEFORE
-      required: false
-      join-classpath: false
-    MythicLib:
      load: OMIT
      required: false
      join-classpath: true
@@ -61,11 +56,7 @@ dependencies:
      required: false
      join-classpath: true
    eco:
-      load: BEFORE
-      required: false
-      join-classpath: true
-    EcoItems:
-      load: BEFORE
+      load: OMIT
      required: false
      join-classpath: true
    MythicMobs:
@@ -77,7 +68,7 @@ dependencies:
      required: false
      join-classpath: true
    KGenerators:
-      load: BEFORE
+      load: OMIT
      required: false
      join-classpath: true
    Multiverse-Core:
@@ -85,6 +76,6 @@ dependencies:
      required: false
      join-classpath: true
    WorldEdit:
-      load: BEFORE
+      load: OMIT
      required: false
      join-classpath: true
@@ -3,18 +3,6 @@ version: ${version}
 main: ${main}
 folia-supported: true
 load: STARTUP
-softdepend:
-  - PlaceholderAPI
-  - CraftEngine
-  - Nexo
-  - Oraxen
-  - ItemsAdder
-  - SCore
-  - ExecutableItems
-  - eco
-  - EcoItems
-  - KGenerators
-  - WorldEdit
 loadbefore: [ Multiverse-Core ]
 authors: [ cyberpwn, NextdoorPsycho, Vatuu ]
 website: VolmitSoftware.com
@@ -23,6 +11,9 @@ commands:
  iris:
    aliases: [ ir, irs ]
 permissions:
+  iris.update:
+    description: Allows viewing Iris updates in VolmLib's combined update reports.
+    default: op
  iris.debugdump:
    description: Allows creating and optionally uploading diagnostic reports.
    default: op
@@ -0,0 +1,46 @@
+{
+  "name": "Flat",
+  "derivative": "minecraft:snowy_plains",
+  "vanillaDerivative": "minecraft:snowy_plains",
+  "layers": [
+    {
+      "minHeight": 1,
+      "maxHeight": 1,
+      "palette": [
+        {
+          "block": "minecraft:lime_wool"
+        }
+      ]
+    },
+    {
+      "minHeight": 384,
+      "maxHeight": 384,
+      "palette": [
+        {
+          "block": "minecraft:green_concrete"
+        }
+      ]
+    }
+  ],
+  "generators": [
+    {
+      "generator": "flat",
+      "min": 96,
+      "max": 96
+    }
+  ],
+  "decorators": [
+    {
+      "palette": [
+        {
+          "block": "craftengine:default/flower_basket",
+          "data": {
+            "variant": "ground"
+          }
+        }
+      ],
+      "chance": 1,
+      "forcePlace": true
+    }
+  ]
+}
@@ -0,0 +1,39 @@
+{
+  "name": "CraftEngine Imported Feature Fixture",
+  "version": 1,
+  "mode": {
+    "type": "OVERWORLD"
+  },
+  "regions": [
+    "flat"
+  ],
+  "focusRegion": "flat",
+  "focus": "flat",
+  "landChance": 1,
+  "environment": "NORMAL",
+  "dimensionHeight": {
+    "min": -64,
+    "max": 320
+  },
+  "logicalHeight": 384,
+  "fluidHeight": 0,
+  "bedrock": false,
+  "rockPalette": {
+    "palette": [
+      {
+        "block": "minecraft:red_concrete"
+      }
+    ]
+  },
+  "importedStructures": {
+    "disabled": [
+      "minecraft:"
+    ]
+  },
+  "importedFeatures": {
+    "enabled": true,
+    "steps": [
+      "TOP_LAYER_MODIFICATION"
+    ]
+  }
+}
@@ -0,0 +1,15 @@
+{
+  "interpolator": {
+    "function": "NONE",
+    "horizontalScale": 1
+  },
+  "seed": 310,
+  "composite": [
+    {
+      "seed": 310,
+      "style": {
+        "style": "FLAT"
+      }
+    }
+  ]
+}
@@ -0,0 +1,12 @@
+{
+  "name": "Flat",
+  "landBiomes": [
+    "flat"
+  ],
+  "seaBiomes": [
+    "flat"
+  ],
+  "shoreBiomes": [
+    "flat"
+  ]
+}
@@ -0,0 +1,35 @@
+plugins {
+    id 'java'
+}
+
+version = '1.0.0'
+
+repositories {
+    mavenCentral()
+    maven { url = 'https://repo.papermc.io/repository/maven-public/' }
+}
+
+dependencies {
+    compileOnly files(providers.gradleProperty('irisJar').get())
+    compileOnly files(providers.gradleProperty('craftEngineJar').get())
+    compileOnly 'io.papermc.paper:paper-api:26.1.2.build.74-stable'
+}
+
+java {
+    toolchain.languageVersion = JavaLanguageVersion.of(25)
+}
+
+sourceSets {
+    main {
+        java.srcDirs = ['src']
+        resources.srcDirs = ['resources']
+    }
+}
+
+tasks.withType(JavaCompile).configureEach {
+    options.compilerArgs += '-parameters'
+}
+
+tasks.named('jar') {
+    archiveBaseName = 'IrisCraftEngineNativeFixture'
+}
@@ -0,0 +1,12 @@
+name: IrisCraftEngineNativeFixture
+version: 1.0.0
+main: art.arcane.iris.fixture.CraftEngineNativeFixture
+api-version: '26.1.2'
+folia-supported: true
+depend: [Iris, CraftEngine]
+commands:
+  iriscenative:
+    permission: iriscenative.run
+permissions:
+  iriscenative.run:
+    default: op
@@ -0,0 +1 @@
+rootProject.name = 'iris-craftengine-native-fixture'
@@ -0,0 +1,385 @@
+package art.arcane.iris.fixture;
+
+import art.arcane.iris.generation.block.IrisCustomData;
+import art.arcane.iris.generation.block.TileData;
+import art.arcane.iris.generation.mantle.DeferredPlacementRecords;
+import art.arcane.iris.generation.mantle.CustomBlockOwnership;
+import art.arcane.iris.generation.runtime.Engine;
+import art.arcane.iris.integration.ExternalDataSVC;
+import art.arcane.iris.integration.Identifier;
+import art.arcane.iris.platform.generation.EngineBukkitOps;
+import art.arcane.iris.spi.IrisServices;
+import art.arcane.iris.world.IrisCreator;
+import art.arcane.iris.world.IrisToolbelt;
+import art.arcane.iris.world.storage.matter.TileWrapper;
+import art.arcane.iris.world.task.J;
+import art.arcane.volmlib.nativelib.terrain.NativeBlockChangeSet;
+import art.arcane.volmlib.util.mantle.flag.MantleFlag;
+import art.arcane.volmlib.util.mantle.runtime.Mantle;
+import art.arcane.volmlib.util.matter.Matter;
+import net.momirealms.craftengine.bukkit.api.CraftEngineBlocks;
+import net.momirealms.craftengine.bukkit.api.CraftEngineFurniture;
+import net.momirealms.craftengine.core.util.Key;
+import org.bukkit.Bukkit;
+import org.bukkit.Chunk;
+import org.bukkit.GameMode;
+import org.bukkit.Location;
+import org.bukkit.Material;
+import org.bukkit.NamespacedKey;
+import org.bukkit.World;
+import org.bukkit.block.Block;
+import org.bukkit.block.data.BlockData;
+import org.bukkit.command.Command;
+import org.bukkit.command.CommandSender;
+import org.bukkit.entity.Entity;
+import org.bukkit.entity.Player;
+import org.bukkit.plugin.java.JavaPlugin;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.CompletableFuture;
+import java.util.logging.Level;
+
+public final class CraftEngineNativeFixture extends JavaPlugin {
+    private static final NamespacedKey WORLD_KEY = new NamespacedKey("iris", "ce_native_probe");
+    private static final NamespacedKey FEATURE_WORLD_KEY = new NamespacedKey("iris", "ce_native_feature_probe");
+    private static final int TEST_Y = 180;
+    private static final int TEST_Z = 8;
+    private static final String BLOCK_ID = "craftengine:default/topaz_ore";
+    private static final String FURNITURE_ID = "craftengine:default/flower_basket[variant=ground]";
+
+    @Override
+    public boolean onCommand(CommandSender sender, Command command, String label, String[] arguments) {
+        if (!(sender instanceof Player player) || arguments.length != 1) {
+            sender.sendMessage("CE_FAILED Use /iriscenative prepare|pending|neighbor|loaded|features|restart from a player");
+            return true;
+        }
+        if (arguments[0].equals("prepare")) {
+            player.setGameMode(GameMode.CREATIVE);
+            prepare(player);
+            return true;
+        }
+        if (arguments[0].equals("features")) {
+            importedFeatures(player);
+            return true;
+        }
+        World world = Bukkit.getWorld(WORLD_KEY);
+        if (world == null) {
+            fail(player, new IllegalStateException("Fixture world has not been created"));
+            return true;
+        }
+        if (arguments[0].equals("restart")) {
+            loadChunks().thenCompose(ignored -> J.runRegionFuture(world, 0, 0,
+                    () -> later(player, world, () -> restarted(player, world))))
+                    .whenComplete((ignored, failure) -> {
+                        if (failure != null) {
+                            fail(player, failure);
+                        }
+                    });
+            return true;
+        }
+        J.runRegionFuture(world, 0, 0, () -> {
+            switch (arguments[0]) {
+                case "pending" -> pending(player, world);
+                case "neighbor" -> neighbor(player, world);
+                case "loaded" -> invalidateLoaded(player, world, IrisToolbelt.access(world).getEngine());
+                default -> throw new IllegalArgumentException("Unknown fixture operation");
+            }
+        }).whenComplete((ignored, failure) -> {
+            if (failure != null) {
+                fail(player, failure);
+            }
+        });
+        return true;
+    }
+
+    private void prepare(Player player) {
+        CompletableFuture.runAsync(() -> {
+            if (Bukkit.getWorld(WORLD_KEY) == null) {
+                try {
+                    new IrisCreator().name(WORLD_KEY.toString()).dimension("ce-native-fixture")
+                            .seed(78264193L).create();
+                } catch (Exception failure) {
+                    throw new IllegalStateException("Could not create CraftEngine fixture world", failure);
+                }
+            }
+        }).thenCompose(ignored -> loadChunks()).thenCompose(ignored -> {
+            World world = Bukkit.getWorld(WORLD_KEY);
+            return J.runRegionFuture(world, 0, 0, () -> preparePlatform(world));
+        }).thenAccept(ignored -> {
+            World world = Bukkit.getWorld(WORLD_KEY);
+            if (!J.runEntity(player, () -> player.teleportAsync(new Location(world, 8.5, TEST_Y + 3, 8.5))
+                    .whenComplete((teleported, failure) -> {
+                        if (failure != null || !Boolean.TRUE.equals(teleported)) {
+                            fail(player, failure == null ? new IllegalStateException("Fixture teleport failed") : failure);
+                            return;
+                        }
+                        player.sendMessage("CE_READY world=" + WORLD_KEY + " folia=" + J.isFolia());
+                    }))) {
+                throw new IllegalStateException("Could not schedule fixture teleport");
+            }
+        }).exceptionally(failure -> {
+            fail(player, failure);
+            return null;
+        });
+    }
+
+    private void importedFeatures(Player player) {
+        CompletableFuture.runAsync(() -> {
+            if (Bukkit.getWorld(FEATURE_WORLD_KEY) == null) {
+                try {
+                    new IrisCreator().name(FEATURE_WORLD_KEY.toString()).dimension("ce-native-feature-fixture")
+                            .seed(78264193L).create();
+                } catch (Exception failure) {
+                    throw new IllegalStateException("Could not create imported feature fixture world", failure);
+                }
+            }
+        }).thenCompose(ignored -> {
+            World world = Bukkit.getWorld(FEATURE_WORLD_KEY);
+            return world.getChunkAtAsync(0, 0, true);
+        }).thenCompose(chunk -> J.runRegionFuture(chunk.getWorld(), 0, 0, () -> {
+            World world = chunk.getWorld();
+            Engine engine = IrisToolbelt.access(world).getEngine();
+            int snow = 0;
+            int pending = 0;
+            for (int x = 0; x < 16; x++) {
+                for (int z = 0; z < 16; z++) {
+                    if (world.getBlockAt(x, 97, z).getType() == Material.SNOW) {
+                        snow++;
+                    }
+                    if (engine.getMantle().getMantle().get(x, 97 - engine.getMinHeight(), z, Identifier.class) != null) {
+                        pending++;
+                    }
+                }
+            }
+            require(snow == 256, "Imported snow feature did not cover all 256 test columns: " + snow);
+            require(pending == 0, "Imported feature left pending furniture records: " + pending);
+            for (Entity entity : chunk.getEntities()) {
+                require(!CraftEngineFurniture.isFurniture(entity), "Imported snow feature left generated furniture");
+            }
+            if (!J.runEntity(player, () -> player.teleportAsync(new Location(world, 8.5, 101, 8.5))
+                    .whenComplete((teleported, failure) -> {
+                        if (failure != null || !Boolean.TRUE.equals(teleported)) {
+                            fail(player, failure == null ? new IllegalStateException("Feature world teleport failed") : failure);
+                            return;
+                        }
+                        player.sendMessage("CE_FEATURES snow=256 pending=0 furniture=0");
+                    }))) {
+                throw new IllegalStateException("Could not schedule feature world teleport");
+            }
+        })).exceptionally(failure -> {
+            fail(player, failure);
+            return null;
+        });
+    }
+
+    private CompletableFuture<Void> loadChunks() {
+        World world = Bukkit.getWorld(WORLD_KEY);
+        require(world != null && IrisToolbelt.isIrisWorld(world), "Fixture must use a real Iris world");
+        List<CompletableFuture<Void>> chunks = new ArrayList<>(15);
+        for (int x = -1; x <= 3; x++) {
+            for (int z = -1; z <= 1; z++) {
+                chunks.add(world.getChunkAtAsync(x, z, true).thenCompose(chunk ->
+                        J.runRegionFuture(world, chunk.getX(), chunk.getZ(), () -> chunk.addPluginChunkTicket(this))));
+            }
+        }
+        return CompletableFuture.allOf(chunks.toArray(CompletableFuture[]::new));
+    }
+
+    private void preparePlatform(World world) {
+        require(CraftEngineBlocks.byId(Key.of("default:topaz_ore")) != null, "CraftEngine default block is missing");
+        require(CraftEngineFurniture.byId(Key.of("default:flower_basket")) != null, "CraftEngine furniture is missing");
+        for (int chunkX = 0; chunkX <= 2; chunkX++) {
+            for (Entity entity : world.getChunkAt(chunkX, 0).getEntities()) {
+                if (CraftEngineFurniture.isFurniture(entity)) {
+                    CraftEngineFurniture.remove(entity, false, false);
+                }
+            }
+        }
+        for (int x = 0; x <= 47; x++) {
+            for (int z = 2; z <= 14; z++) {
+                world.getBlockAt(x, TEST_Y - 1, z).setType(Material.STONE, false);
+                for (int y = TEST_Y; y <= TEST_Y + 5; y++) {
+                    world.getBlockAt(x, y, z).setType(Material.AIR, false);
+                }
+            }
+        }
+    }
+
+    private void pending(Player player, World world) {
+        Engine engine = IrisToolbelt.access(world).getEngine();
+        Mantle<Matter> mantle = engine.getMantle().getMantle();
+        queue(engine, world, 2, BLOCK_ID);
+        queue(engine, world, 4, BLOCK_ID);
+        queue(engine, world, 6, BLOCK_ID);
+        queue(engine, world, 8, BLOCK_ID);
+        queue(engine, world, 10, FURNITURE_ID);
+        queue(engine, world, 12, FURNITURE_ID);
+        Block chest = world.getBlockAt(14, TEST_Y, TEST_Z);
+        chest.setType(Material.CHEST, false);
+        mantle.set(14, TEST_Y - engine.getMinHeight(), TEST_Z, new TileWrapper(TileData.getTileState(chest, false)));
+        world.getBlockAt(4, TEST_Y, TEST_Z).setType(Material.AIR, false);
+        world.getBlockAt(6, TEST_Y, TEST_Z).setType(Material.COBBLESTONE, false);
+
+        NativeBlockChangeSet changes = DeferredPlacementRecords.track(engine, bounds(world));
+        changes.add(8, TEST_Y, TEST_Z);
+        changes.add(12, TEST_Y - 1, TEST_Z);
+        changes.add(12, TEST_Y, TEST_Z);
+        changes.add(14, TEST_Y, TEST_Z);
+        world.getBlockAt(8, TEST_Y, TEST_Z).setType(Material.AIR, false);
+        world.getBlockAt(12, TEST_Y - 1, TEST_Z).setType(Material.AIR, false);
+        chest.setType(Material.COBBLESTONE, false);
+        DeferredPlacementRecords.invalidate(engine, changes);
+        require(record(engine, 8, Identifier.class) == null, "Native cut retained a pending custom record");
+        require(record(engine, 12, Identifier.class) == null, "Flatten column retained pending furniture");
+        require(record(engine, 14, TileWrapper.class) == null, "Native wall retained pending chest data");
+        require(record(engine, 2, Identifier.class) != null, "Native writes invalidated an untouched custom record");
+        replay(engine, world, 0);
+        CustomBlockOwnership ownership = record(engine, 10, CustomBlockOwnership.class);
+        require(record(engine, 2, Identifier.class) == null, "Custom materialization did not consume pending records");
+        require(CraftEngineBlocks.isCustomBlock(world.getBlockAt(2, TEST_Y, TEST_Z)), "Intact custom block was not placed");
+        require(world.getBlockAt(4, TEST_Y, TEST_Z).getType().isAir(), "Cut custom block was resurrected");
+        require(world.getBlockAt(6, TEST_Y, TEST_Z).getType() == Material.COBBLESTONE, "Custom block replaced native wall");
+        require(world.getBlockAt(8, TEST_Y, TEST_Z).getType().isAir(), "Invalidated custom block was resurrected");
+        require(chest.getType() == Material.COBBLESTONE, "Chest data replaced native wall");
+        later(player, world, () -> {
+            int intactFurniture = furnitureAt(world, 10);
+            require(intactFurniture == 1, "Intact furniture count is " + intactFurniture
+                    + "; pending=" + record(engine, 10, Identifier.class)
+                    + "; ownership=" + ownership
+                    + "; chunkEntities=" + world.getChunkAt(0, 0).getEntities().length);
+            require(furnitureAt(world, 12) == 0, "Flattened furniture was resurrected");
+            player.sendMessage("CE_PENDING intact=1 air=1 wall=1 invalidated=1 flatten=1 chest=1 furniture=1");
+        });
+    }
+
+    private void neighbor(Player player, World world) {
+        Engine engine = IrisToolbelt.access(world).getEngine();
+        queue(engine, world, 18, FURNITURE_ID);
+        queue(engine, world, 20, FURNITURE_ID);
+        queue(engine, world, 22, FURNITURE_ID);
+        queue(engine, world, 42, FURNITURE_ID);
+        replay(engine, world, 1);
+        replay(engine, world, 2);
+        world.getBlockAt(40, TEST_Y, TEST_Z).setType(Material.DIAMOND_BLOCK, false);
+        later(player, world, () -> {
+            require(furnitureAt(world, 18) == 1 && furnitureAt(world, 20) == 1
+                    && furnitureAt(world, 22) == 1, "Neighbor furniture did not materialize");
+            require(furnitureAt(world, 42) == 1 && record(engine, 42, CustomBlockOwnership.class) != null,
+                    "Regeneration target furniture did not materialize with saved ownership");
+            if (!J.runEntity(player, () -> player.teleportAsync(new Location(world, 40.5, TEST_Y + 3, TEST_Z + 0.5))
+                    .whenComplete((teleported, failure) -> {
+                        if (failure != null || !Boolean.TRUE.equals(teleported)) {
+                            fail(player, failure == null ? new IllegalStateException("Regeneration target teleport failed") : failure);
+                            return;
+                        }
+                        player.sendMessage("CE_NEIGHBOR_READY chunk=2,0 furniture=3 target=1");
+                    }))) {
+                throw new IllegalStateException("Could not schedule regeneration target teleport");
+            }
+        });
+    }
+
+    private void invalidateLoaded(Player player, World world, Engine engine) {
+        require(world.getBlockAt(40, TEST_Y, TEST_Z).getType().isAir(), "Adjacent target chunk did not regenerate");
+        require(furnitureAt(world, 18) == 1 && furnitureAt(world, 20) == 1
+                && furnitureAt(world, 22) == 1, "Neighbor furniture did not materialize");
+        NativeBlockChangeSet changes = DeferredPlacementRecords.track(engine, bounds(world));
+        changes.add(18, TEST_Y - 1, TEST_Z);
+        changes.add(18, TEST_Y, TEST_Z);
+        changes.add(22, TEST_Y, TEST_Z);
+        world.getBlockAt(18, TEST_Y - 1, TEST_Z).setType(Material.AIR, false);
+        world.getBlockAt(18, TEST_Y, TEST_Z).setType(Material.COBBLESTONE, false);
+        DeferredPlacementRecords.invalidate(engine, changes);
+        require(CraftEngineFurniture.place(new Location(world, 22.5, TEST_Y, TEST_Z + 0.5),
+                Key.of("default:flower_basket"), "ground", false) != null,
+                "Could not place replacement furniture before scheduled cleanup");
+        later(player, world, () -> {
+            require(furnitureAt(world, 42) == 0, "Regeneration retained target chunk furniture");
+            require(furnitureAt(world, 18) == 0, "Native write left materialized neighbor furniture");
+            require(furnitureAt(world, 20) == 1, "Native write removed untouched neighbor furniture");
+            require(furnitureAt(world, 22) == 1, "Native cleanup removed replacement furniture or retained the old one");
+            require(world.getBlockAt(18, TEST_Y, TEST_Z).getType() == Material.COBBLESTONE,
+                    "Furniture cleanup replaced the native wall");
+            player.sendMessage("CE_LOADED removed=1 untouched=1 replacement=1 wall=1 target=1");
+        });
+    }
+
+    private void restarted(Player player, World world) {
+        require(furnitureAt(world, 20) == 1, "Generated neighbor furniture did not survive restart");
+        require(furnitureAt(world, 10) == 1, "Untouched furniture did not survive restart");
+        Engine engine = IrisToolbelt.access(world).getEngine();
+        NativeBlockChangeSet changes = DeferredPlacementRecords.track(engine, bounds(world));
+        changes.add(20, TEST_Y, TEST_Z);
+        DeferredPlacementRecords.invalidate(engine, changes);
+        later(player, world, () -> {
+            require(furnitureAt(world, 20) == 0, "Persisted furniture ownership was not invalidated after restart");
+            require(furnitureAt(world, 10) == 1, "Restart cleanup removed untouched furniture");
+            player.sendMessage("CE_RESTART removed=1 untouched=1");
+        });
+    }
+
+    private void queue(Engine engine, World world, int x, String identifier) {
+        ExternalDataSVC service = IrisServices.get(ExternalDataSVC.class);
+        BlockData data = service.getBlockData(Identifier.fromString(identifier)).orElseThrow();
+        require(data instanceof IrisCustomData, "Iris did not resolve real CraftEngine content: " + identifier);
+        IrisCustomData custom = (IrisCustomData) data;
+        world.getBlockAt(x, TEST_Y, TEST_Z).setBlockData(custom.getBase(), false);
+        engine.getMantle().getMantle().set(x, TEST_Y - engine.getMinHeight(), TEST_Z, custom.getCustom());
+    }
+
+    private <T> T record(Engine engine, int x, Class<T> type) {
+        return engine.getMantle().getMantle().get(x, TEST_Y - engine.getMinHeight(), TEST_Z, type);
+    }
+
+    private void replay(Engine engine, World world, int chunkX) {
+        Mantle<Matter> mantle = engine.getMantle().getMantle();
+        for (int x = chunkX - 1; x <= chunkX + 1; x++) {
+            for (int z = -1; z <= 1; z++) {
+                require(world.isChunkLoaded(x, z), "Replay neighbor is not loaded: " + x + "," + z);
+            }
+        }
+        require(mantle.isLoaded(world.getChunkAt(chunkX, 0)), "Replay mantle chunk is not loaded: " + chunkX);
+        mantle.flag(chunkX, 0, MantleFlag.ETCHED, false);
+        mantle.flag(chunkX, 0, MantleFlag.TILE, false);
+        mantle.flag(chunkX, 0, MantleFlag.CUSTOM, false);
+        EngineBukkitOps.updateChunk(engine, world.getChunkAt(chunkX, 0), mantle);
+    }
+
+    private int furnitureAt(World world, int x) {
+        int count = 0;
+        for (Entity entity : world.getChunkAt(x >> 4, TEST_Z >> 4).getEntities()) {
+            Location location = entity.getLocation();
+            if (location.getBlockX() == x && location.getBlockY() == TEST_Y && location.getBlockZ() == TEST_Z
+                    && CraftEngineFurniture.getLoadedFurnitureByMetaEntity(entity) != null) {
+                count++;
+            }
+        }
+        return count;
+    }
+
+    private void later(Player player, World world, Runnable assertion) {
+        Bukkit.getRegionScheduler().runDelayed(this, new Location(world, 8, TEST_Y, TEST_Z), task -> {
+            try {
+                assertion.run();
+            } catch (Throwable failure) {
+                fail(player, failure);
+            }
+        }, 20);
+    }
+
+    private NativeBlockChangeSet.Bounds bounds(World world) {
+        return new NativeBlockChangeSet.Bounds(-1, -1, 3, 1, world.getMinHeight(), world.getMaxHeight() - world.getMinHeight());
+    }
+
+    private void require(boolean condition, String message) {
+        if (!condition) {
+            throw new IllegalStateException(message);
+        }
+    }
+
+    private void fail(CommandSender sender, Throwable failure) {
+        getLogger().log(Level.SEVERE, "CraftEngine native placement assertion failed", failure);
+        sender.sendMessage("CE_FAILED " + failure.getMessage());
+    }
+}
@@ -0,0 +1,32 @@
+{
+  "name": "Flat",
+  "derivative": "minecraft:plains",
+  "vanillaDerivative": "minecraft:plains",
+  "layers": [
+    {
+      "minHeight": 1,
+      "maxHeight": 1,
+      "palette": [
+        {
+          "block": "minecraft:lime_wool"
+        }
+      ]
+    },
+    {
+      "minHeight": 384,
+      "maxHeight": 384,
+      "palette": [
+        {
+          "block": "minecraft:green_concrete"
+        }
+      ]
+    }
+  ],
+  "generators": [
+    {
+      "generator": "flat",
+      "min": 96,
+      "max": 96
+    }
+  ]
+}
@@ -0,0 +1,33 @@
+{
+  "name": "CraftEngine Native Fixture",
+  "version": 1,
+  "mode": {
+    "type": "OVERWORLD"
+  },
+  "regions": [
+    "flat"
+  ],
+  "focusRegion": "flat",
+  "focus": "flat",
+  "landChance": 1,
+  "environment": "NORMAL",
+  "dimensionHeight": {
+    "min": -64,
+    "max": 320
+  },
+  "logicalHeight": 384,
+  "fluidHeight": 0,
+  "bedrock": false,
+  "rockPalette": {
+    "palette": [
+      {
+        "block": "minecraft:red_concrete"
+      }
+    ]
+  },
+  "importedStructures": {
+    "disabled": [
+      "minecraft:"
+    ]
+  }
+}
@@ -0,0 +1,15 @@
+{
+  "interpolator": {
+    "function": "NONE",
+    "horizontalScale": 1
+  },
+  "seed": 310,
+  "composite": [
+    {
+      "seed": 310,
+      "style": {
+        "style": "FLAT"
+      }
+    }
+  ]
+}
@@ -0,0 +1,12 @@
+{
+  "name": "Flat",
+  "landBiomes": [
+    "flat"
+  ],
+  "seaBiomes": [
+    "flat"
+  ],
+  "shoreBiomes": [
+    "flat"
+  ]
+}
@@ -0,0 +1,15 @@
+import { readFile } from 'node:fs/promises'
+import path from 'node:path'
+
+export default {
+  name: 'iris-craftengine-native-restart',
+  description: 'Verify persisted generated furniture ownership after a full server restart.',
+  async run(context) {
+    const source = await readFile(path.join(context.server.directory, '.server-source'), 'utf8')
+    context.expect(/^isolated=true\s*$/m.test(source), 'CraftEngine regression requires an isolated instance')
+    await context.step('native writes remove persisted ownership after restart', async () => {
+      const response = await context.command('/iriscenative restart', /CE_RESTART|CE_FAILED/, 60000)
+      context.expect(response.includes('CE_RESTART removed=1 untouched=1'), response)
+    })
+  }
+}
@@ -0,0 +1,49 @@
+import { readFile } from 'node:fs/promises'
+import path from 'node:path'
+
+export default {
+  name: 'iris-craftengine-native',
+  description: 'Verify deferred native invalidation and loaded neighbor cleanup with real Iris and CraftEngine.',
+  async run(context) {
+    const source = await readFile(path.join(context.server.directory, '.server-source'), 'utf8')
+    context.expect(/^isolated=true\s*$/m.test(source), 'CraftEngine regression requires an isolated instance')
+    await context.step('create and enter a real Iris world with CraftEngine content', async () => {
+      const response = await context.command('/iriscenative prepare', /CE_READY|CE_FAILED/, 180000)
+      context.expect(response.includes('CE_READY'), response)
+    })
+    await context.step('native writes remove pending block, chest, and flatten furniture records', async () => {
+      const response = await context.command('/iriscenative pending', /CE_PENDING|CE_FAILED/, 60000)
+      context.expect(response.includes('CE_PENDING intact=1 air=1 wall=1 invalidated=1 flatten=1 chest=1 furniture=1'), response)
+      await context.waitUntil(() => {
+        const origin = context.bot.entity.position.floored()
+        const cut = context.bot.blockAt(origin.set(4, 180, 8))
+        const wall = context.bot.blockAt(origin.set(6, 180, 8))
+        const invalidated = context.bot.blockAt(origin.set(8, 180, 8))
+        const chest = context.bot.blockAt(origin.set(14, 180, 8))
+        return cut?.name === 'air' && wall?.name === 'cobblestone'
+          && invalidated?.name === 'air' && chest?.name === 'cobblestone'
+      }, { label: 'Client observes retained native air and walls', timeoutMs: 30000, intervalMs: 100 })
+    })
+    await context.step('regeneration removes target furniture and preserves neighbor ownership', async () => {
+      const ready = await context.command('/iriscenative neighbor', /CE_NEIGHBOR_READY|CE_FAILED/, 30000)
+      context.expect(ready.includes('CE_NEIGHBOR_READY chunk=2,0 furniture=3 target=1'), ready)
+      const regenerated = await context.command('/iris developer regen radius=0', /Regen complete:|Regen failed:/, 90000)
+      context.expect(regenerated.includes('Regen complete:'), regenerated)
+      const response = await context.command('/iriscenative loaded', /CE_LOADED|CE_FAILED/, 30000)
+      context.expect(response.includes('CE_LOADED removed=1 untouched=1 replacement=1 wall=1 target=1'), response)
+    })
+    await context.step('imported snow features replace generated furniture records', async () => {
+      const response = await context.command('/iriscenative features', /CE_FEATURES|CE_FAILED/, 180000)
+      context.expect(response.includes('CE_FEATURES snow=256 pending=0 furniture=0'), response)
+      await context.waitUntil(() => {
+        const position = context.bot.entity.position.floored()
+        for (let x = 0; x < 16; x++) {
+          for (let z = 0; z < 16; z++) {
+            if (context.bot.blockAt(position.set(x, 97, z))?.name !== 'snow') return false
+          }
+        }
+        return true
+      }, { label: 'Client observes 256 imported snow layers', timeoutMs: 30000, intervalMs: 100 })
+    })
+  }
+}
@@ -0,0 +1,47 @@
+{
+  "name": "Flat",
+  "derivative": "minecraft:plains",
+  "vanillaDerivative": "minecraft:plains",
+  "layers": [
+    {
+      "minHeight": 1,
+      "maxHeight": 1,
+      "palette": [
+        {
+          "block": "minecraft:lime_wool"
+        }
+      ]
+    },
+    {
+      "minHeight": 384,
+      "maxHeight": 384,
+      "palette": [
+        {
+          "block": "minecraft:green_concrete"
+        }
+      ]
+    }
+  ],
+  "generators": [
+    {
+      "generator": "flat",
+      "min": 96,
+      "max": 96
+    }
+  ],
+  "decorators": [
+    {
+      "palette": [
+        {
+          "block": "minecraft:oak_stairs",
+          "data": {
+            "half": "bottom",
+            "facing": "north"
+          }
+        }
+      ],
+      "chance": 1,
+      "forcePlace": true
+    }
+  ]
+}
@@ -0,0 +1,28 @@
+{
+  "name": "Decorator Fixture",
+  "version": 1,
+  "mode": {
+    "type": "OVERWORLD"
+  },
+  "regions": [
+    "flat"
+  ],
+  "focusRegion": "flat",
+  "focus": "flat",
+  "landChance": 1,
+  "environment": "NORMAL",
+  "dimensionHeight": {
+    "min": -64,
+    "max": 320
+  },
+  "logicalHeight": 384,
+  "fluidHeight": 0,
+  "bedrock": false,
+  "rockPalette": {
+    "palette": [
+      {
+        "block": "minecraft:red_concrete"
+      }
+    ]
+  }
+}
@@ -0,0 +1,15 @@
+{
+  "interpolator": {
+    "function": "NONE",
+    "horizontalScale": 1
+  },
+  "seed": 310,
+  "composite": [
+    {
+      "seed": 310,
+      "style": {
+        "style": "FLAT"
+      }
+    }
+  ]
+}
@@ -0,0 +1,12 @@
+{
+  "name": "Flat",
+  "landBiomes": [
+    "flat"
+  ],
+  "seaBiomes": [
+    "flat"
+  ],
+  "shoreBiomes": [
+    "flat"
+  ]
+}
@@ -0,0 +1,40 @@
+import { readFile } from 'node:fs/promises'
+import path from 'node:path'
+
+export default {
+  name: 'iris-decorators',
+  description: 'Verify authored stair decorations occupy one block and retain their half state.',
+  async run(context) {
+    const source = await readFile(path.join(context.server.directory, '.server-source'), 'utf8')
+    context.expect(/^isolated=true\s*$/m.test(source), 'Decorator generation requires an isolated instance')
+    await context.step('create a world with authored stair decorations', async () => {
+      const response = await context.command('/iris create name=decorator_probe type=decorator-fixture seed=78264193',
+        /Successfully created your world|Failed to create/, 180000)
+      context.expect(response.includes('Successfully created your world'), response)
+    })
+    await context.step('client sees single bottom-half stair decorations', async () => {
+      let checked = 0
+      await context.waitUntil(() => {
+        checked = 0
+        const center = context.bot.entity.position.floored()
+        for (let x = -6; x <= 6; x++) {
+          for (let z = -6; z <= 6; z++) {
+            for (let y = -4; y <= 1; y++) {
+              const position = center.offset(x, y, z)
+              if (context.bot.blockAt(position)?.name !== 'lime_wool') continue
+              const decoration = context.bot.blockAt(position.offset(0, 1, 0))
+              const above = context.bot.blockAt(position.offset(0, 2, 0))
+              if (!decoration || !above) return false
+              if (decoration.name !== 'oak_stairs' || decoration.getProperties().half !== 'bottom'
+                || above.name !== 'air') return false
+              checked++
+            }
+          }
+        }
+        return checked >= 100
+      }, { label: 'At least 100 authored stair columns with empty space above', timeoutMs: 60000, intervalMs: 250 })
+      context.expect(checked >= 100, 'Client verified generated decorator columns', { checked })
+      context.report.decoratorColumns = checked
+    })
+  }
+}
@@ -2,6 +2,7 @@ name: IrisNativeLifecycleFixture
 version: 1.0.0
 main: art.arcane.iris.fixture.NativeLifecycleFixture
 api-version: '26.1.2'
+folia-supported: true
 depend: [Iris]
 commands:
  irislifecycle:
@@ -1,11 +1,31 @@
 package art.arcane.iris.fixture;

+import art.arcane.iris.Iris;
 import art.arcane.volmlib.nativelib.NativeAdapters;
 import art.arcane.iris.world.runtime.RuntimeInjection;
+import art.arcane.iris.generation.runtime.Engine;
+import art.arcane.iris.structure.placement.IrisStructureLocator;
 import art.arcane.iris.world.IrisCreator;
+import art.arcane.iris.world.task.J;
 import art.arcane.iris.world.IrisToolbelt;
+import art.arcane.iris.world.IrisWorldStorage;
+import art.arcane.iris.world.WorldCreatorCompat;
+import art.arcane.iris.world.lifecycle.LifecycleOperationCoordinator;
+import art.arcane.iris.platform.bootstrap.ServerProperties;
+import org.bukkit.Location;
+import org.bukkit.entity.Player;
+import org.bukkit.configuration.file.YamlConfiguration;
 import org.bukkit.Material;
 import org.bukkit.block.Biome;
+import org.bukkit.block.Container;
+import org.bukkit.loot.Lootable;
+import org.bukkit.loot.LootTable;
+import org.bukkit.inventory.Inventory;
+import org.bukkit.inventory.ItemStack;
+import org.bukkit.inventory.meta.MapMeta;
+import org.bukkit.map.MapView;
+import org.bukkit.generator.structure.Structure;
+import org.bukkit.util.StructureSearchResult;
 import art.arcane.volmlib.nativelib.terrain.NativeTerrainAccess;
 import art.arcane.volmlib.nativelib.terrain.NativeStructureReader;
 import art.arcane.volmlib.nativelib.terrain.NativeWorldRuntime;
@@ -19,6 +39,10 @@ import org.bukkit.command.CommandSender;
 import org.bukkit.generator.ChunkGenerator;
 import org.bukkit.plugin.java.JavaPlugin;

+import java.io.File;
+import java.nio.file.Files;
+import java.nio.file.LinkOption;
+import java.nio.file.Path;
 import java.util.concurrent.CompletableFuture;
 import java.util.List;
 import java.util.logging.Level;
@@ -26,12 +50,16 @@ import java.util.logging.Level;
 public final class NativeLifecycleFixture extends JavaPlugin implements WorldRuntimeExecution {
    private static final NamespacedKey WORLD_KEY = NamespacedKey.minecraft("native_lifecycle_probe");
    private static final NamespacedKey TERRAIN_KEY = new NamespacedKey("iris", "native_terrain_probe");
+    private static final NamespacedKey COMMAND_KEY = new NamespacedKey("iris", "lifecycle_probe");
+    private static final NamespacedKey TREASURE_KEY = new NamespacedKey("iris", "treasure_map_probe");
    private static final long WORLD_SEED = 78264193L;
    private NativeWorldRuntime runtime;
+    private TreasureLootChecks treasureLootChecks;

    @Override
    public void onEnable() {
        runtime = NativeAdapters.require(NativeWorldRuntime.class);
+        treasureLootChecks = new TreasureLootChecks(this);
        NativeTerrainAccess terrain = NativeAdapters.require(NativeTerrainAccess.class);
        getLogger().info("Native lifecycle ready: " + runtime.description()
                + "; terrain provider=" + terrain.getClass().getName());
@@ -44,18 +72,40 @@ public final class NativeLifecycleFixture extends JavaPlugin implements WorldRun

    @Override
    public boolean onCommand(CommandSender sender, Command command, String label, String[] arguments) {
-        if (arguments.length != 1) {
-            sender.sendMessage("Use /irislifecycle create|unload|status|structures|terrain-create|terrain-check|terrain-unload");
+        if (arguments.length == 0) {
+            sender.sendMessage("Use /irislifecycle create|unload|status|structures|terrain-create|terrain-check|terrain-unload|lifecycle-status|lifecycle-entry");
            return true;
        }
        try {
            switch (arguments[0]) {
+                case "treasure-map-create" -> createTreasureMapWorld(sender);
+                case "treasure-map-limit" -> runTreasureRegion(sender, () -> checkTreasureMapLimit(sender));
+                case "treasure-map-chest" -> {
+                    if (arguments.length != 3) {
+                        throw new IllegalArgumentException("Use treasure-map-chest <destination> <CHEST|COPPER_CHEST>");
+                    }
+                    runTreasureRegion(sender, () -> prepareTreasureMapChest(sender, arguments[1], arguments[2]));
+                }
+                case "treasure-map-inspect" -> {
+                    if (arguments.length != 2) {
+                        throw new IllegalArgumentException("Use treasure-map-inspect <destination>");
+                    }
+                    runTreasureRegion(sender, () -> inspectTreasureMapChest(sender, arguments[1]));
+                }
+                case "treasure-map-check" -> runTreasureRegion(sender, () -> verifyTreasureMapLoot(sender));
+                case "treasure-extra-check" -> runTreasureRegion(sender, () -> treasureLootChecks.verify(sender));
+                case "treasure-region-check" -> runTreasureRegion(sender, () -> treasureLootChecks.verifyRegion(sender));
+                case "treasure-reload-before" -> runTreasureRegion(sender, () -> treasureLootChecks.verifyReload(sender, false));
+                case "treasure-reload-after" -> runTreasureRegion(sender, () -> treasureLootChecks.verifyReload(sender, true));
+                case "treasure-resources" -> treasureLootChecks.reportResourceReloads(sender);
                case "create" -> create(sender);
                case "unload" -> unload(sender);
                case "structures" -> structures(sender);
                case "terrain-create" -> createTerrain(sender);
                case "terrain-check" -> checkTerrain(sender);
                case "terrain-unload" -> unloadTerrain(sender);
+                case "lifecycle-status" -> lifecycleStatus(sender);
+                case "lifecycle-entry" -> lifecycleEntry(sender);
                case "status" -> sender.sendMessage("NATIVE_STATUS available=" + runtime.available()
                        + " loaded=" + (Bukkit.getWorld(WORLD_KEY) != null));
                default -> throw new IllegalArgumentException("Unknown lifecycle operation");
@@ -66,6 +116,232 @@ public final class NativeLifecycleFixture extends JavaPlugin implements WorldRun
        return true;
    }

+    private void createTreasureMapWorld(CommandSender sender) {
+        if (!(sender instanceof Player player)) {
+            throw new IllegalStateException("Treasure map fixture requires a player");
+        }
+        runTreasureRegion(sender, () -> prepareTreasureMapWorld(player));
+    }
+
+    private void runTreasureRegion(CommandSender sender, Runnable task) {
+        ensureTreasureMapWorld()
+                .thenCompose(ignored -> J.runRegionFuture(Bukkit.getWorld(TREASURE_KEY), 0, 0, task))
+                .whenComplete((ignored, failure) -> {
+                    if (failure != null) {
+                        fail(sender, failure);
+                    }
+                });
+    }
+
+    private CompletableFuture<?> ensureTreasureMapWorld() {
+        if (Bukkit.getWorld(TREASURE_KEY) != null) {
+            return CompletableFuture.completedFuture(null);
+        }
+        if (WorldCreatorCompat.persistentLevelRoot(TREASURE_KEY).exists()) {
+            return Iris.instance.worldReconciler().loadWorld(ServerProperties.BUKKIT_YML, TREASURE_KEY.toString());
+        }
+        return runAsync(() -> {
+            try {
+                new IrisCreator().name(TREASURE_KEY.toString()).dimension("treasure-map-fixture")
+                        .seed(WORLD_SEED).create();
+            } catch (Exception failure) {
+                throw new IllegalStateException("Treasure map fixture creation failed", failure);
+            }
+        });
+    }
+
+    private void prepareTreasureMapWorld(Player player) {
+        World world = Bukkit.getWorld(TREASURE_KEY);
+        if (world == null || !IrisToolbelt.isIrisWorld(world) || world.getSeed() != WORLD_SEED
+                || !"treasure-map-fixture".equals(IrisToolbelt.access(world).getEngine().getDimension().getLoadKey())) {
+            throw new IllegalStateException("Treasure map fixture world identity is invalid");
+        }
+        for (int x = 0; x <= 8; x++) {
+            for (int z = 0; z <= 8; z++) {
+                world.getBlockAt(x, 160, z).setType(Material.STONE, false);
+                for (int y = 161; y <= 164; y++) {
+                    world.getBlockAt(x, y, z).setType(Material.AIR, false);
+                }
+            }
+        }
+        if (!J.runEntity(player, () -> player.teleportAsync(new Location(world, 0.5, 161, 0.5)).whenComplete((teleported, failure) -> {
+            if (failure != null) {
+                fail(player, failure);
+            } else if (!Boolean.TRUE.equals(teleported)) {
+                fail(player, new IllegalStateException("Treasure map fixture teleport failed"));
+            } else {
+                player.sendMessage("TREASURE_MAP_READY world=" + TREASURE_KEY
+                        + " version=" + Bukkit.getMinecraftVersion() + " folia=" + J.isFolia());
+            }
+        }))) {
+            throw new IllegalStateException("Could not schedule treasure map fixture teleport");
+        }
+    }
+
+    private void checkTreasureMapLimit(CommandSender sender) {
+        World world = Bukkit.getWorld(TREASURE_KEY);
+        if (world == null) {
+            throw new IllegalStateException("Treasure map fixture world is absent");
+        }
+        Engine engine = IrisToolbelt.access(world).getEngine();
+        IrisStructureLocator.LocateResult located = IrisStructureLocator.locateInPlacementRings(
+                engine, "minecraft:buried_treasure", 2, 2, 50, (x, z) -> true);
+        if (located.status() != IrisStructureLocator.LocateStatus.SEARCH_LIMIT_REACHED) {
+            throw new IllegalStateException("Blocked treasure placement returned " + located.status());
+        }
+        sender.sendMessage("TREASURE_MAP_LIMIT status=" + located.status());
+    }
+
+    private void prepareTreasureMapChest(CommandSender sender, String destination, String material) {
+        World world = Bukkit.getWorld(TREASURE_KEY);
+        treasureMapChest(world, destination, material);
+        sender.sendMessage("TREASURE_MAP_CHEST destination=" + destination + " material=" + material);
+    }
+
+    private Container treasureMapChest(World world, String destination, String material) {
+        requireTreasureDestination(destination);
+        if (!List.of("CHEST", "COPPER_CHEST").contains(material)) {
+            throw new IllegalArgumentException("Unknown treasure map container: " + material);
+        }
+        LootTable loot = Bukkit.getLootTable(new NamespacedKey("iris_qa", destination));
+        if (loot == null) {
+            throw new IllegalStateException("Treasure map loot table is absent: " + destination);
+        }
+        world.getBlockAt(2, 161, 2).setType(Material.AIR, false);
+        world.getBlockAt(2, 161, 2).setType(Material.valueOf(material), false);
+        Container chest = (Container) world.getBlockAt(2, 161, 2).getState();
+        ((Lootable) chest).setLootTable(loot);
+        ((Lootable) chest).setSeed(WORLD_SEED);
+        if (!chest.update(true, false)) {
+            throw new IllegalStateException("Treasure map loot chest was not installed");
+        }
+        return (Container) world.getBlockAt(2, 161, 2).getState();
+    }
+
+    private void verifyTreasureMapLoot(CommandSender sender) {
+        checkTreasureMapLimit(sender);
+        World world = Bukkit.getWorld(TREASURE_KEY);
+        for (String destination : List.of("blocked", "disabled", "found", "mixed")) {
+            Inventory inventory = treasureMapChest(world, destination, "CHEST").getInventory();
+            inspectTreasureMapChest(sender, destination);
+            inventory.remove(Material.DIAMOND);
+            Inventory reopened = ((Container) world.getBlockAt(2, 161, 2).getState()).getInventory();
+            if (reopened.contains(Material.DIAMOND)
+                    || !(reopened.contains(Material.FILLED_MAP) || reopened.contains(Material.MAP))) {
+                throw new IllegalStateException("Reopening changed " + destination + " chest loot");
+            }
+        }
+        sender.sendMessage("TREASURE_MAP_CHECK destinations=4 retained=true");
+    }
+
+    private void inspectTreasureMapChest(CommandSender sender, String destination) {
+        requireTreasureDestination(destination);
+        World world = Bukkit.getWorld(TREASURE_KEY);
+        Inventory inventory = ((Container) world.getBlockAt(2, 161, 2).getState()).getInventory();
+        ItemStack map = null;
+        int diamonds = 0;
+        for (ItemStack item : inventory.getContents()) {
+            if (item == null) {
+                continue;
+            }
+            if ((item.getType() == Material.MAP || item.getType() == Material.FILLED_MAP)
+                    && item.getAmount() == 1 && map == null) {
+                map = item;
+            } else if (item.getType() == Material.DIAMOND) {
+                diamonds += item.getAmount();
+            } else {
+                throw new IllegalStateException("Unexpected chest loot: " + item);
+            }
+        }
+        if (map == null || diamonds != 1) {
+            throw new IllegalStateException("Invalid " + destination + " chest: map=" + map + " diamonds=" + diamonds);
+        }
+        boolean expectedLocated = destination.equals("found") || destination.equals("mixed");
+        MapView view = map.getItemMeta() instanceof MapMeta meta && meta.hasMapView() ? meta.getMapView() : null;
+        if ((view != null) != expectedLocated) {
+            throw new IllegalStateException("Unexpected map data for " + destination + ": " + map);
+        }
+        String result = "TREASURE_MAP_INSPECT destination=" + destination + " diamonds=1 located=" + expectedLocated;
+        if (view != null) {
+            StructureSearchResult target = world.locateNearestStructure(
+                    new Location(world, 2, 161, 2), Structure.DESERT_PYRAMID, 50, false);
+            if (target == null || target.getStructure() != Structure.DESERT_PYRAMID) {
+                throw new IllegalStateException("Map has no verified pyramid target");
+            }
+            int targetX = target.getLocation().getBlockX();
+            int targetZ = target.getLocation().getBlockZ();
+            if (view.getWorld() != world || view.getScale() != MapView.Scale.CLOSEST
+                    || view.getCenterX() != Math.floorDiv(targetX + 64, 128) * 128
+                    || view.getCenterZ() != Math.floorDiv(targetZ + 64, 128) * 128) {
+                throw new IllegalStateException("Map data does not cover the verified pyramid at " + target.getLocation());
+            }
+            result += " mapId=" + view.getId() + " targetX=" + targetX + " targetZ=" + targetZ
+                    + " centerX=" + view.getCenterX() + " centerZ=" + view.getCenterZ();
+        }
+        sender.sendMessage(result);
+    }
+
+    private void requireTreasureDestination(String destination) {
+        if (!List.of("blocked", "disabled", "found", "mixed").contains(destination)) {
+            throw new IllegalArgumentException("Unknown treasure map destination: " + destination);
+        }
+    }
+
+    private void lifecycleStatus(CommandSender sender) throws Exception {
+        World world = Bukkit.getWorld(COMMAND_KEY);
+        Path storage = WorldCreatorCompat.persistentLevelRoot(COMMAND_KEY).toPath();
+        Path levelRoot = IrisWorldStorage.levelRoot().toPath();
+        Path registry = levelRoot.resolve("iris/worlds.json");
+        boolean registered = Files.exists(registry)
+                && Files.readString(registry).contains("\"" + COMMAND_KEY + "\"");
+        String startupName = IrisWorldStorage.configuredWorldName(COMMAND_KEY, levelRoot.getFileName().toString());
+        YamlConfiguration configuration = YamlConfiguration.loadConfiguration(ServerProperties.BUKKIT_YML);
+        boolean configured = configuration.getConfigurationSection("worlds") != null
+                && configuration.getConfigurationSection("worlds").contains(startupName);
+        File quarantineRoot = levelRoot.resolve("dimensions/iris").toFile();
+        File[] quarantines = quarantineRoot.listFiles((directory, name) -> name.startsWith(".iris-delete-"));
+        int quarantineCount = quarantines == null ? 0 : quarantines.length;
+        Path queueFile = Bukkit.getPluginManager().getPlugin("Iris").getDataFolder().toPath()
+                .resolve("pending-world-deletes.txt");
+        List<String> queue = Files.exists(queueFile) ? Files.readAllLines(queueFile) : List.of();
+        boolean queued = quarantineCount > 0;
+        if (quarantines != null) {
+            for (File quarantine : quarantines) {
+                queued &= queue.contains(quarantine.getName());
+            }
+        }
+        boolean disk = Files.exists(storage, LinkOption.NOFOLLOW_LINKS);
+        String cleanup = disk ? "present" : quarantineCount == 0 ? "deleted" : queued ? "queued" : "unsafe";
+        boolean idle = true;
+        LifecycleOperationCoordinator coordinator = LifecycleOperationCoordinator.get();
+        for (LifecycleOperationCoordinator.Domain domain : LifecycleOperationCoordinator.Domain.values()) {
+            idle &= coordinator.active(domain).isEmpty();
+        }
+        sender.sendMessage("IRIS_LIFECYCLE loaded=" + (world != null) + " registered=" + registered
+                + " configured=" + configured + " disk=" + disk + " quarantines=" + quarantineCount
+                + " cleanup=" + cleanup + " idle=" + idle);
+    }
+
+    private void lifecycleEntry(CommandSender sender) {
+        if (!(sender instanceof Player player)) {
+            throw new IllegalArgumentException("Lifecycle entry requires a player");
+        }
+        World world = Bukkit.getWorld(COMMAND_KEY);
+        if (world == null || player.getWorld() != world || world.getSeed() != WORLD_SEED
+                || !IrisToolbelt.isIrisWorld(world)) {
+            throw new IllegalStateException("Player did not enter the requested seeded Iris world");
+        }
+        Location feet = player.getLocation();
+        Material floor = world.getBlockAt(feet.getBlockX(), feet.getBlockY() - 1, feet.getBlockZ()).getType();
+        if (floor != Material.LIME_WOOL || !floor.isSolid()
+                || !world.getBlockAt(feet.getBlockX(), feet.getBlockY(), feet.getBlockZ()).isPassable()
+                || !world.getBlockAt(feet.getBlockX(), feet.getBlockY() + 1, feet.getBlockZ()).isPassable()) {
+            throw new IllegalStateException("Lifecycle player entry lacks a safe fixture floor");
+        }
+        sender.sendMessage("IRIS_LIFECYCLE_ENTRY world=" + COMMAND_KEY + " seed=" + world.getSeed()
+                + " floor=lime_wool safe=true");
+    }
+
    private void create(CommandSender sender) throws ReflectiveOperationException {
        if (!runtime.available() || Bukkit.getWorld(WORLD_KEY) != null) {
            throw new IllegalStateException("Native runtime unavailable or probe world already loaded");
@@ -124,6 +400,7 @@ public final class NativeLifecycleFixture extends JavaPlugin implements WorldRun
                        int y = world.getHighestBlockYAt(x, z);
                        if (y < 90 || y > 100 || world.getBlockAt(x, y, z).getType() != Material.LIME_WOOL
                                || world.getBlockAt(x, y - 3, z).getType() != Material.GREEN_CONCRETE
+                                || world.getBlockAt(x, world.getMinHeight(), z).getType() != Material.GREEN_CONCRETE
                                || world.getBiome(x, y, z) != Biome.PLAINS) {
                            throw new IllegalStateException("Terrain column differs at " + x + "," + y + "," + z
                                    + ": " + world.getBlockAt(x, y, z).getType());
@@ -212,11 +489,11 @@ public final class NativeLifecycleFixture extends JavaPlugin implements WorldRun
    }

    public boolean regionized() {
-        return false;
+        return J.isFolia();
    }

    public boolean primaryThread() {
-        return Bukkit.isPrimaryThread();
+        return J.isFolia() ? Bukkit.isGlobalTickThread() : Bukkit.isPrimaryThread();
    }

    public CompletableFuture<Void> runGlobal(Runnable task) {
@@ -229,10 +506,10 @@ public final class NativeLifecycleFixture extends JavaPlugin implements WorldRun
                result.completeExceptionally(failure);
            }
        };
-        if (Bukkit.isPrimaryThread()) {
+        if (primaryThread()) {
            wrapped.run();
-        } else {
-            Bukkit.getScheduler().runTask(this, wrapped);
+        } else if (!J.runGlobal(wrapped)) {
+            result.completeExceptionally(new IllegalStateException("Could not schedule fixture task"));
        }
        return result;
    }
@@ -0,0 +1,259 @@
+package art.arcane.iris.fixture;
+
+import art.arcane.iris.generation.runtime.Engine;
+import art.arcane.iris.platform.bukkit.BukkitBlockResolution;
+import art.arcane.iris.platform.generation.EngineBukkitOps;
+import art.arcane.iris.world.IrisToolbelt;
+import art.arcane.iris.world.loot.InventorySlotType;
+import art.arcane.iris.world.loot.IrisVanillaLootTable;
+import art.arcane.iris.world.loot.IrisLootTable;
+import art.arcane.volmlib.util.collection.KList;
+import art.arcane.volmlib.util.mantle.runtime.MantleChunk;
+import art.arcane.iris.world.task.J;
+import art.arcane.volmlib.util.matter.Matter;
+import io.papermc.paper.event.world.StructuresLocateEvent;
+import io.papermc.paper.event.server.ServerResourcesReloadedEvent;
+import io.papermc.paper.math.Position;
+import org.bukkit.Bukkit;
+import org.bukkit.Location;
+import org.bukkit.Material;
+import org.bukkit.NamespacedKey;
+import org.bukkit.World;
+import org.bukkit.block.Block;
+import org.bukkit.block.Container;
+import org.bukkit.block.Chest;
+import org.bukkit.command.CommandSender;
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.Listener;
+import org.bukkit.event.world.LootGenerateEvent;
+import org.bukkit.generator.structure.Structure;
+import org.bukkit.inventory.ItemStack;
+import org.bukkit.inventory.Inventory;
+import org.bukkit.plugin.java.JavaPlugin;
+import org.bukkit.util.StructureSearchResult;
+
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Proxy;
+import java.util.Collection;
+import java.util.List;
+import java.util.concurrent.atomic.AtomicInteger;
+
+public final class TreasureLootChecks implements Listener {
+    private static final NamespacedKey WORLD_KEY = new NamespacedKey("iris", "treasure_map_probe");
+    private static final List<String> CHESTS = List.of(
+            "CHEST", "COPPER_CHEST", "EXPOSED_COPPER_CHEST", "WEATHERED_COPPER_CHEST",
+            "OXIDIZED_COPPER_CHEST", "WAXED_COPPER_CHEST", "WAXED_EXPOSED_COPPER_CHEST",
+            "WAXED_WEATHERED_COPPER_CHEST", "WAXED_OXIDIZED_COPPER_CHEST");
+    private final IrisVanillaLootTable reloadTable = new IrisVanillaLootTable("iris_qa:reload");
+    private final AtomicInteger resourceReloads = new AtomicInteger();
+    private LocateAction locateAction = LocateAction.PASS;
+    private int locateEvents;
+    private int lootEvents;
+    private boolean lootEventsOwned = true;
+
+    public TreasureLootChecks(JavaPlugin plugin) {
+        Bukkit.getPluginManager().registerEvents(this, plugin);
+    }
+
+    public void verify(CommandSender sender) {
+        World world = requireWorld();
+        verifyCopperLoot(world);
+        sender.sendMessage("TREASURE_COPPER_LOOT variants=8 normal=true diamonds=1");
+        verifyInventoryRollback(world);
+        sender.sendMessage("TREASURE_LOOT_ROLLBACK contents=true nativeTable=true seed=true retry=true");
+        verifyLocateEvents(world);
+        sender.sendMessage("TREASURE_LOCATE_EVENTS cancelled=true replaced=true calls=2");
+        sender.sendMessage("TREASURE_EXTRA_CHECK variants=9 rollback=true locateEvents=true");
+    }
+
+    public void verifyRegion(CommandSender sender) {
+        World world = requireWorld();
+        if (!J.isOwnedByCurrentRegion(world, 0, 0)) {
+            throw new IllegalStateException("Fixture does not own its loot region");
+        }
+        lootEvents = 0;
+        lootEventsOwned = true;
+        verifyCopperLoot(world);
+        if (lootEvents != CHESTS.size() || !lootEventsOwned) {
+            throw new IllegalStateException("Loot event ownership failed: count=" + lootEvents
+                    + " owned=" + lootEventsOwned);
+        }
+        sender.sendMessage("TREASURE_REGION_LOOT copper=8 normal=1 events=" + lootEvents
+                + " owned=true folia=" + J.isFolia());
+    }
+
+    @EventHandler
+    public void onLoot(LootGenerateEvent event) {
+        if (event.getWorld().getKey().equals(WORLD_KEY) && event.isPlugin()) {
+            Location origin = event.getLootContext().getLocation();
+            lootEvents++;
+            lootEventsOwned &= J.isOwnedByCurrentRegion(event.getWorld(),
+                    origin.getBlockX() >> 4, origin.getBlockZ() >> 4);
+        }
+    }
+
+    public void verifyReload(CommandSender sender, boolean reloaded) {
+        World world = requireWorld();
+        Material expected = reloaded ? Material.EMERALD : Material.DIAMOND;
+        Collection<ItemStack> items = reloadTable.getLoot(
+                false, 783L, InventorySlotType.STORAGE, world, 2, 161, 2);
+        if (items.size() != 1 || items.iterator().next().getType() != expected) {
+            throw new IllegalStateException("Reloaded loot did not contain " + expected + ": " + items);
+        }
+        sender.sendMessage("TREASURE_RELOAD material=" + expected);
+    }
+
+    public void reportResourceReloads(CommandSender sender) {
+        sender.sendMessage("TREASURE_RESOURCES revision=" + resourceReloads.get());
+    }
+
+    @EventHandler
+    public void onResourcesReloaded(ServerResourcesReloadedEvent event) {
+        resourceReloads.incrementAndGet();
+    }
+
+    @EventHandler
+    public void onLocate(StructuresLocateEvent event) {
+        if (!event.getWorld().getKey().equals(WORLD_KEY) || locateAction == LocateAction.PASS) {
+            return;
+        }
+        locateEvents++;
+        if (locateAction == LocateAction.CANCEL) {
+            event.setCancelled(true);
+        } else {
+            event.setResult(new StructuresLocateEvent.Result(Position.block(123, 100, 456), Structure.DESERT_PYRAMID));
+        }
+    }
+
+    private void verifyCopperLoot(World world) {
+        Engine engine = IrisToolbelt.access(world).getEngine();
+        Block block = world.getBlockAt(4, 161, 4);
+        MantleChunk<Matter> mantle = engine.getMantle().getMantle().useChunk(block.getChunk());
+        try {
+            for (String name : CHESTS) {
+                block.setType(Material.AIR, false);
+                block.setType(Material.valueOf(name), false);
+                if (!BukkitBlockResolution.isStorageChest(block.getBlockData())) {
+                    throw new IllegalStateException("Chest is excluded from Iris loot: " + name);
+                }
+                EngineBukkitOps.update(engine, 4, 161, 4, block.getChunk(), mantle);
+                Container chest = (Container) block.getState();
+                int diamonds = 0;
+                for (ItemStack item : chest.getInventory().getContents()) {
+                    if (item == null) {
+                        continue;
+                    }
+                    if (item.getType() != Material.DIAMOND) {
+                        throw new IllegalStateException("Unexpected " + name + " loot: " + item);
+                    }
+                    diamonds += item.getAmount();
+                }
+                if (diamonds != 1) {
+                    throw new IllegalStateException(name + " contains " + diamonds + " diamonds");
+                }
+            }
+        } finally {
+            mantle.release();
+        }
+    }
+
+    private void verifyInventoryRollback(World world) {
+        Engine engine = IrisToolbelt.access(world).getEngine();
+        Block block = world.getBlockAt(6, 161, 4);
+        block.setType(Material.AIR, false);
+        block.setType(Material.CHEST, false);
+        Chest chest = (Chest) block.getState();
+        chest.getBlockInventory().setItem(0, new ItemStack(Material.EMERALD, 3));
+        chest = (Chest) block.getState();
+        NamespacedKey key = new NamespacedKey("iris_qa", "reload");
+        chest.setLootTable(Bukkit.getLootTable(key));
+        chest.setSeed(913L);
+        if (!chest.update(true, false)) {
+            throw new IllegalStateException("Could not set native loot for rollback check");
+        }
+        Inventory inventory = chest.getBlockInventory();
+        IllegalStateException injected = new IllegalStateException("Fixture insertion interruption");
+        Inventory interrupted = (Inventory) Proxy.newProxyInstance(Inventory.class.getClassLoader(),
+                new Class<?>[]{Inventory.class}, (proxy, method, arguments) -> {
+                    Object result;
+                    try {
+                        result = method.invoke(inventory, arguments);
+                    } catch (InvocationTargetException failure) {
+                        throw failure.getCause();
+                    }
+                    if (method.getName().equals("addItem")) {
+                        throw injected;
+                    }
+                    return result;
+                });
+        KList<IrisLootTable> tables = new KList<>();
+        tables.add(new IrisVanillaLootTable("iris_qa:reload"));
+        try {
+            EngineBukkitOps.addItems(engine, false, interrupted, tables, InventorySlotType.STORAGE,
+                    world, 6, 161, 4);
+            throw new IllegalStateException("Interrupted insertion did not fail");
+        } catch (IllegalStateException failure) {
+            if (failure != injected) {
+                throw failure;
+            }
+        }
+        Chest restored = (Chest) block.getState();
+        if (restored.getLootTable() == null || !restored.getLootTable().getKey().equals(key)
+                || restored.getSeed() != 913L) {
+            throw new IllegalStateException("Rollback lost the native loot table or seed");
+        }
+        ItemStack existing = restored.getSnapshotInventory().getItem(0);
+        if (existing == null || existing.getType() != Material.EMERALD || existing.getAmount() != 3) {
+            throw new IllegalStateException("Rollback lost the original contents: " + existing);
+        }
+        EngineBukkitOps.addItems(engine, false, restored.getBlockInventory(), tables, InventorySlotType.STORAGE,
+                world, 6, 161, 4);
+        int diamonds = 0;
+        int emeralds = 0;
+        for (ItemStack item : restored.getBlockInventory().getContents()) {
+            if (item == null) {
+                continue;
+            }
+            if (item.getType() == Material.DIAMOND) {
+                diamonds += item.getAmount();
+            } else if (item.getType() == Material.EMERALD) {
+                emeralds += item.getAmount();
+            }
+        }
+        if (diamonds != 2 || emeralds != 3 || ((Chest) block.getState()).getLootTable() != null) {
+            throw new IllegalStateException("Loot retry failed: diamonds=" + diamonds + " emeralds=" + emeralds);
+        }
+    }
+
+    private void verifyLocateEvents(World world) {
+        Location origin = new Location(world, 2, 161, 2);
+        locateEvents = 0;
+        try {
+            locateAction = LocateAction.CANCEL;
+            if (world.locateNearestStructure(origin, Structure.DESERT_PYRAMID, 50, false) != null) {
+                throw new IllegalStateException("Cancelled structure search returned a target");
+            }
+            locateAction = LocateAction.REPLACE;
+            StructureSearchResult result = world.locateNearestStructure(origin, Structure.DESERT_PYRAMID, 50, false);
+            if (result == null || result.getStructure() != Structure.DESERT_PYRAMID
+                    || result.getLocation().getBlockX() != 123 || result.getLocation().getBlockY() != 100
+                    || result.getLocation().getBlockZ() != 456 || locateEvents != 2) {
+                throw new IllegalStateException("Structure search ignored event result: " + result);
+            }
+        } finally {
+            locateAction = LocateAction.PASS;
+        }
+    }
+
+    private World requireWorld() {
+        World world = Bukkit.getWorld(WORLD_KEY);
+        if (world == null || !IrisToolbelt.isIrisWorld(world)) {
+            throw new IllegalStateException("Treasure map fixture world is absent");
+        }
+        return world;
+    }
+
+    private enum LocateAction {
+        PASS, CANCEL, REPLACE
+    }
+}
@@ -11,6 +11,15 @@
          "block": "minecraft:lime_wool"
        }
      ]
+    },
+    {
+      "minHeight": 384,
+      "maxHeight": 384,
+      "palette": [
+        {
+          "block": "minecraft:green_concrete"
+        }
+      ]
    }
  ],
  "generators": [
@@ -21,7 +21,7 @@
  "rockPalette": {
    "palette": [
      {
-        "block": "minecraft:green_concrete"
+        "block": "minecraft:red_concrete"
      }
    ]
  }
@@ -0,0 +1,61 @@
+import { readFile } from 'node:fs/promises'
+import path from 'node:path'
+
+const world = 'native-terrain-support'
+const air = new Set(['air', 'cave_air', 'void_air'])
+
+export default {
+  name: 'iris-native-terrain-support',
+  description: 'Verify native terrain fitting preserves buried caves and excludes trees from lowered ground.',
+  async run(context) {
+    const bot = context.bot
+    const source = await readFile(path.join(context.server.directory, '.server-source'), 'utf8')
+    context.expect(/^isolated=true\s*$/m.test(source), 'Requires an isolated instance')
+    const position = bot.entity.position.clone()
+    const at = (x, y, z) => bot.blockAt(position.clone().set(x, y, z))
+    const teleport = async (x, y, z) => {
+      await context.command(`/minecraft:tp @s ${x + 0.5} ${y} ${z + 0.5}`, /Teleported/i, 60000)
+      await context.waitUntil(() => Math.abs(bot.entity.position.x - x - 0.5) < 1
+        && Math.abs(bot.entity.position.z - z - 0.5) < 1 && at(x, y, z),
+      { label: 'Coordinate chunk received', timeoutMs: 90000, intervalMs: 100 })
+    }
+    await context.step('enter the seeded overworld', async () => {
+      if (context.options.command !== 'reuse') {
+        await context.command(`/iris create name=${world} type=overworld seed=1337`,
+          /Successfully created your world/i, 240000)
+      }
+      await context.command(`/iris tp ${world}`)
+      await context.waitUntil(async () => {
+        const snapshot = await context.observe()
+        const player = snapshot.players.find(entry => entry.username === bot.username)
+        return snapshot.worlds.some(entry => entry.id === player?.world && entry.name.endsWith(world))
+      }, { label: 'Entered seeded overworld', timeoutMs: 90000, intervalMs: 100 })
+      await context.command('/minecraft:gamemode spectator @s', /Spectator Mode/i)
+      await context.command('/minecraft:seed', /Seed:.*1337/)
+    })
+    await context.step('preserve caves beneath the ruined portal terrain skirt', async () => {
+      await teleport(995, 44, -3611)
+      await context.waitUntil(() => at(990, 43, -3626) && at(992, 43, -3627),
+        { label: 'Cave columns received', timeoutMs: 90000, intervalMs: 100 })
+      for (const [x, z, bottom, top] of [[990, -3626, 33, 54], [992, -3627, 34, 55]]) {
+        for (let y = bottom; y <= top; y++) {
+          const block = at(x, y, z)
+          context.expect(block && air.has(block.name), 'Native terrain fitting filled a buried cave',
+            { x, y, z, material: block?.name })
+        }
+        await context.command(`/execute if block ${x} 43 ${z} minecraft:cave_air run say CAVE_PRESERVED_${x}`,
+          new RegExp(`CAVE_PRESERVED_${x}`))
+      }
+    })
+    await context.step('exclude the pine whose support is removed by village grading', async () => {
+      await teleport(-2601, 174, -7063)
+      await context.waitUntil(() => at(-2601, 167, -7063),
+        { label: 'Pine column received', timeoutMs: 90000, intervalMs: 100 })
+      const block = at(-2601, 167, -7063)
+      context.expect(air.has(block.name), 'Tree remains above terrain removed by native grading',
+        { x: -2601, y: 167, z: -7063, material: block.name })
+      await context.command('/execute if block -2601 167 -7063 minecraft:air run say PINE_EXCLUDED',
+        /PINE_EXCLUDED/)
+    })
+  }
+}
@@ -0,0 +1,35 @@
+plugins {
+    id 'java'
+}
+
+version = '1.0.0'
+
+repositories {
+    mavenCentral()
+    maven { url = 'https://repo.papermc.io/repository/maven-public/' }
+}
+
+dependencies {
+    compileOnly files(providers.gradleProperty('irisJar').get())
+    compileOnly files(providers.gradleProperty('irisGsonJar').get())
+    compileOnly 'io.papermc.paper:paper-api:26.1.2.build.74-stable'
+}
+
+java {
+    toolchain.languageVersion = JavaLanguageVersion.of(25)
+}
+
+sourceSets {
+    main {
+        java.srcDirs = ['src']
+        resources.srcDirs = ['resources']
+    }
+}
+
+tasks.withType(JavaCompile).configureEach {
+    options.compilerArgs += '-parameters'
+}
+
+tasks.named('jar') {
+    archiveBaseName = 'IrisNaturalSpawningFixture'
+}
@@ -0,0 +1,12 @@
+name: IrisNaturalSpawningFixture
+version: 1.0.0
+main: art.arcane.iris.fixture.NaturalSpawningFixture
+api-version: '26.1.2'
+folia-supported: true
+depend: [Iris]
+commands:
+  irisspawnqa:
+    permission: irisspawnqa.run
+permissions:
+  irisspawnqa.run:
+    default: op
@@ -0,0 +1 @@
+rootProject.name = 'iris-natural-spawning-fixture'
@@ -0,0 +1,701 @@
+package art.arcane.iris.fixture;
+
+import art.arcane.iris.configuration.IrisSettings;
+import art.arcane.iris.generation.biome.IrisBiome;
+import art.arcane.iris.generation.runtime.BiomeEnvironment;
+import art.arcane.iris.generation.runtime.Engine;
+import art.arcane.iris.world.IrisCreator;
+import art.arcane.iris.world.entity.IrisSpawner;
+import art.arcane.iris.world.entity.IrisMarker;
+import art.arcane.iris.world.entity.EntitySpawnSeed;
+import art.arcane.volmlib.util.mantle.flag.MantleFlag;
+import art.arcane.iris.pack.value.IrisPosition;
+import art.arcane.volmlib.util.math.RNG;
+import art.arcane.iris.world.entity.IrisEntitySpawn;
+import art.arcane.iris.world.entity.IrisEntity;
+import art.arcane.iris.platform.bukkit.BukkitPlatform;
+import art.arcane.iris.platform.bukkit.BukkitEntityType;
+import art.arcane.iris.world.IrisToolbelt;
+import art.arcane.iris.world.history.SavedBiomeUnavailableException;
+import org.bukkit.Bukkit;
+import org.bukkit.Chunk;
+import org.bukkit.Difficulty;
+import org.bukkit.GameMode;
+import org.bukkit.HeightMap;
+import org.bukkit.GameRules;
+import org.bukkit.Location;
+import org.bukkit.Material;
+import org.bukkit.NamespacedKey;
+import org.bukkit.World;
+import org.bukkit.command.Command;
+import org.bukkit.command.CommandSender;
+import org.bukkit.entity.Entity;
+import org.bukkit.entity.EntityType;
+import org.bukkit.entity.LivingEntity;
+import org.bukkit.entity.Player;
+import org.bukkit.inventory.ItemStack;
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.EventPriority;
+import org.bukkit.event.Listener;
+import org.bukkit.event.entity.CreatureSpawnEvent;
+import org.bukkit.plugin.java.JavaPlugin;
+
+import java.lang.reflect.Field;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HexFormat;
+import java.util.List;
+import java.util.Map;
+import java.util.TreeMap;
+import java.util.Set;
+import java.util.concurrent.atomic.AtomicInteger;
+import java.util.concurrent.CompletableFuture;
+import java.util.logging.Level;
+
+public final class NaturalSpawningFixture extends JavaPlugin implements Listener {
+    private static final NamespacedKey WORLD_KEY = new NamespacedKey("iris", "spawn_qa");
+    private static final long WORLD_SEED = 78264193L;
+    private static final int FROG_CAPACITY = 16;
+    private static final int ZOMBIE_CAPACITY = 2;
+    private static final int BIOME_READY_ATTEMPTS = 60;
+    private static final long BIOME_RETRY_TICKS = 10L;
+
+    private boolean previousAmbient;
+    private boolean previousMarkers;
+    private boolean previousForcedPersistence;
+    private volatile boolean ready;
+    private int firstZombieBatch;
+    private int ambientEvents;
+    private int cancelledAmbientEvents;
+    private final ThreadLocal<Boolean> ambientInvocation = ThreadLocal.withInitial(() -> false);
+
+    @Override
+    public void onEnable() {
+        Bukkit.getPluginManager().registerEvents(this, this);
+        previousAmbient = IrisSettings.get().getWorld().isAmbientEntitySpawningSystem();
+        previousMarkers = IrisSettings.get().getWorld().isMarkerEntitySpawningSystem();
+        previousForcedPersistence = IrisSettings.get().getWorld().isForcePersistEntities();
+        IrisSettings.get().getWorld().setAmbientEntitySpawningSystem(false);
+        IrisSettings.get().getWorld().setMarkerEntitySpawningSystem(false);
+        IrisSettings.get().getWorld().setForcePersistEntities(false);
+        getLogger().info("Natural spawning fixture ready; commands use the Iris ambient path on the owning region.");
+    }
+
+    @Override
+    public void onDisable() {
+        IrisSettings.get().getWorld().setAmbientEntitySpawningSystem(previousAmbient);
+        IrisSettings.get().getWorld().setMarkerEntitySpawningSystem(previousMarkers);
+        IrisSettings.get().getWorld().setForcePersistEntities(previousForcedPersistence);
+    }
+
+    @Override
+    public boolean onCommand(CommandSender sender, Command command, String label, String[] arguments) {
+        if (arguments.length != 1) {
+            notifySender(sender, "Use /irisspawnqa setup|frogs|zombies|stress|check|seeded|completion|surface|cave");
+            return true;
+        }
+        try {
+            switch (arguments[0]) {
+                case "setup" -> setup(sender);
+                case "frogs" -> runRegion(sender, () -> spawnFrogs(sender));
+                case "zombies" -> runRegion(sender, () -> spawnZombies(sender));
+                case "stress" -> runRegion(sender, () -> stress(sender));
+                case "check" -> runRegion(sender, () -> check(sender));
+                case "seeded" -> seeded(sender);
+                case "completion" -> completion(sender);
+                case "surface" -> view(sender, 67D);
+                case "cave" -> view(sender, -46D);
+                default -> throw new IllegalArgumentException("Unknown spawning operation");
+            }
+        } catch (Throwable failure) {
+            fail(sender, failure);
+        }
+        return true;
+    }
+
+    @EventHandler(priority = EventPriority.HIGHEST)
+    public void isolateSpawns(CreatureSpawnEvent event) {
+        if (!WORLD_KEY.equals(event.getLocation().getWorld().getKey())) {
+            return;
+        }
+        if (!ambientInvocation.get()) {
+            event.setCancelled(true);
+            return;
+        }
+        ambientEvents++;
+        if (event.isCancelled()) {
+            cancelledAmbientEvents++;
+        }
+    }
+
+    private void setup(CommandSender sender) {
+        if (!(sender instanceof Player)) {
+            throw new IllegalArgumentException("Setup requires a player");
+        }
+        World world = Bukkit.getWorld(WORLD_KEY);
+        if (world != null) {
+            require(IrisToolbelt.isIrisWorld(world) && world.getSeed() == WORLD_SEED,
+                    "Existing fixture key is not the owned Iris world with the expected seed");
+            ready = false;
+            Bukkit.getGlobalRegionScheduler().execute(this, () -> configureWorld(sender, world));
+            return;
+        }
+        ready = false;
+        Bukkit.getAsyncScheduler().runNow(this, task -> createWorld(sender));
+    }
+
+    private void createWorld(CommandSender sender) {
+        try {
+            World world = new IrisCreator().name(WORLD_KEY.toString()).dimension("spawn-qa")
+                    .seed(WORLD_SEED).create();
+            Bukkit.getGlobalRegionScheduler().execute(this, () -> configureWorld(sender, world));
+        } catch (Throwable failure) {
+            fail(sender, failure);
+        }
+    }
+
+    private void configureWorld(CommandSender sender, World world) {
+        try {
+            world.setDifficulty(Difficulty.NORMAL);
+            world.setTime(6000L);
+            world.setStorm(false);
+            world.setThundering(false);
+            world.setGameRule(GameRules.SPAWN_MOBS, true);
+            List<CompletableFuture<Void>> chunks = new ArrayList<>();
+            for (int chunkX = -1; chunkX <= 1; chunkX++) {
+                for (int chunkZ = -1; chunkZ <= 1; chunkZ++) {
+                    chunks.add(retainChunk(world, chunkX, chunkZ));
+                }
+            }
+            CompletableFuture.allOf(chunks.toArray(CompletableFuture[]::new)).whenComplete((ignored, failure) -> {
+                if (failure != null) {
+                    fail(sender, failure);
+                } else {
+                    Bukkit.getRegionScheduler().execute(this, world, 0, 0, () -> prepareChunk(sender, world));
+                }
+            });
+        } catch (Throwable failure) {
+            fail(sender, failure);
+        }
+    }
+
+    private CompletableFuture<Void> retainChunk(World world, int chunkX, int chunkZ) {
+        CompletableFuture<Void> retained = new CompletableFuture<>();
+        world.getChunkAtAsync(chunkX, chunkZ, true).whenComplete((chunk, failure) -> {
+            if (failure != null) {
+                retained.completeExceptionally(failure);
+                return;
+            }
+            Bukkit.getRegionScheduler().execute(this, world, chunkX, chunkZ, () -> {
+                try {
+                    chunk.addPluginChunkTicket(this);
+                    for (Entity entity : chunk.getEntities()) {
+                        if (entity instanceof LivingEntity && !(entity instanceof Player)) {
+                            entity.remove();
+                        }
+                    }
+                    retained.complete(null);
+                } catch (Throwable error) {
+                    retained.completeExceptionally(error);
+                }
+            });
+        });
+        return retained;
+    }
+
+    private void prepareChunk(CommandSender sender, World world) {
+        try {
+            require(WORLD_KEY.equals(world.getKey()) && IrisToolbelt.isIrisWorld(world)
+                    && world.getSeed() == WORLD_SEED, "Fixture world ownership changed");
+            Chunk chunk = world.getChunkAt(0, 0);
+            int removed = 0;
+            for (Entity entity : chunk.getEntities()) {
+                if (entity instanceof LivingEntity && !(entity instanceof Player)) {
+                    entity.remove();
+                    removed++;
+                }
+            }
+            for (Entity entity : chunk.getEntities()) {
+                require(!(entity instanceof LivingEntity) || entity instanceof Player || !entity.isValid(),
+                        "Fixture target chunk retained a living mob after cleanup: " + entity.getType());
+            }
+            getLogger().info("SPAWN_QA_CLEANUP removed=" + removed + " chunk=0,0");
+            firstZombieBatch = 0;
+            ambientEvents = 0;
+            cancelledAmbientEvents = 0;
+            for (int x = 0; x < 16; x++) {
+                for (int z = 0; z < 16; z++) {
+                    chunk.getBlock(x, 64, z).setType(Material.GRASS_BLOCK, false);
+                    for (int y = 65; y <= 68; y++) {
+                        chunk.getBlock(x, y, z).setType(Material.AIR, false);
+                    }
+                    for (int y = -48; y <= -42; y++) {
+                        boolean shell = y == -48 || y == -42 || x == 0 || x == 15 || z == 0 || z == 15;
+                        chunk.getBlock(x, y, z).setType(shell ? Material.STONE : Material.CAVE_AIR, false);
+                    }
+                }
+            }
+            if (!IrisToolbelt.isIrisWorld(world) || world.getSeed() != WORLD_SEED) {
+                throw new IllegalStateException("Fixture is not the requested Iris world");
+            }
+            awaitBiomeEnvironment(sender, world, 0);
+        } catch (Throwable failure) {
+            fail(sender, failure);
+        }
+    }
+
+    private void awaitBiomeEnvironment(CommandSender sender, World world, int attempt) {
+        try {
+            Engine engine = IrisToolbelt.access(world).getEngine();
+            engine.getSurfaceBiomeEnvironment(8, 8);
+            ready = true;
+            teleport(sender, world, 67D, "SPAWN_QA_SETUP world=" + WORLD_KEY + " seed=" + WORLD_SEED);
+        } catch (SavedBiomeUnavailableException unavailable) {
+            if (!unavailable.isLoading() || attempt >= BIOME_READY_ATTEMPTS) {
+                fail(sender, unavailable);
+                return;
+            }
+            Bukkit.getRegionScheduler().runDelayed(this, world, 0, 0,
+                    task -> awaitBiomeEnvironment(sender, world, attempt + 1), BIOME_RETRY_TICKS);
+        } catch (Throwable failure) {
+            fail(sender, failure);
+        }
+    }
+
+    private void completion(CommandSender sender) {
+        World world = requireWorld();
+        Bukkit.getGlobalRegionScheduler().execute(this, () -> {
+            world.setGameRule(GameRules.SPAWN_MOBS, false);
+            runRegion(sender, () -> beginCompletion(sender, world));
+        });
+    }
+
+    private void beginCompletion(CommandSender sender, World world) {
+        try {
+            Engine engine = IrisToolbelt.access(world).getEngine();
+            Object manager = engine.getWorldManager();
+            Field field = manager.getClass().getDeclaredField("chunkMaintenance");
+            field.setAccessible(true);
+            Object maintenance = field.get(manager);
+            Method run = maintenance.getClass().getDeclaredMethod("runInitialSpawn", World.class, int.class, int.class, Runnable.class);
+            run.setAccessible(true);
+            Field pending = maintenance.getClass().getDeclaredField("markerFlagQueue");
+            pending.setAccessible(true);
+            AtomicInteger callbacks = new AtomicInteger();
+            Runnable callback = () -> {
+                require(Bukkit.isOwnedByCurrentRegion(world, 0, 0), "Initial callback ran outside its owning region");
+                callbacks.incrementAndGet();
+                Chunk chunk = world.getChunkAt(0, 0);
+                invokeAmbient(runtimeSpawn(chunk, "seeded"), chunk, true);
+            };
+            run.invoke(maintenance, world, 0, 0, callback);
+            awaitSkippedInitial(sender, world, new CompletionRun(engine, maintenance, run, pending, callback, callbacks), 0);
+        } catch (ReflectiveOperationException failure) {
+            throw new IllegalStateException("Could not start initial completion test", failure);
+        }
+    }
+
+    private void awaitSkippedInitial(CommandSender sender, World world, CompletionRun state, int attempt) {
+        Bukkit.getRegionScheduler().runDelayed(this, world, 0, 0, task -> {
+            try {
+                require(state.callbacks().get() == 0, "Disabled mob spawning consumed the initial pass");
+                if (!((Set<?>) state.pending().get(state.maintenance())).isEmpty()) {
+                    require(attempt < 100, "Skipped initial pass did not release its pending state");
+                    awaitSkippedInitial(sender, world, state, attempt + 1);
+                    return;
+                }
+                Bukkit.getGlobalRegionScheduler().execute(this, () -> {
+                    world.setGameRule(GameRules.SPAWN_MOBS, true);
+                    runRegion(sender, () -> retryInitialCompletion(sender, world, state));
+                });
+            } catch (Throwable failure) {
+                fail(sender, failure);
+            }
+        }, 2L);
+    }
+
+    private void retryInitialCompletion(CommandSender sender, World world, CompletionRun state) {
+        try {
+            state.run().invoke(state.maintenance(), world, 0, 0, state.callback());
+            state.run().invoke(state.maintenance(), world, 0, 0, state.callback());
+            awaitInitialCompletion(sender, world, state, 0);
+        } catch (ReflectiveOperationException failure) {
+            throw new IllegalStateException("Could not retry initial spawning", failure);
+        }
+    }
+
+    private void awaitInitialCompletion(CommandSender sender, World world, CompletionRun state, int attempt) {
+        Bukkit.getRegionScheduler().runDelayed(this, world, 0, 0, task -> {
+            try {
+                if (state.callbacks().get() == 0 || !((Set<?>) state.pending().get(state.maintenance())).isEmpty()) {
+                    require(attempt < 100, "Initial spawning did not complete after retry");
+                    awaitInitialCompletion(sender, world, state, attempt + 1);
+                    return;
+                }
+                require(state.callbacks().get() == 1, "Concurrent initial requests spawned duplicate populations");
+                state.run().invoke(state.maintenance(), world, 0, 0, state.callback());
+                Bukkit.getAsyncScheduler().runNow(this, ignored -> {
+                    try {
+                        require(state.engine().getMantle().getMantle().hasFlag(0, 0, MantleFlag.INITIAL_SPAWNED_MARKER), "Initial completion was not persisted");
+                        require(state.callbacks().get() == 1, "Completed initial pass ran again");
+                        evidence(sender, "SPAWN_QA_COMPLETION retry=true callbacks=1 persisted=true owned=true");
+                    } catch (Throwable failure) {
+                        fail(sender, failure);
+                    }
+                });
+            } catch (Throwable failure) {
+                fail(sender, failure);
+            }
+        }, 2L);
+    }
+
+    private void seeded(CommandSender sender) {
+        requireWorld();
+        List<List<String>> baseline = new ArrayList<>();
+        sampleInitial(0, false).thenCompose(first -> {
+            baseline.add(first);
+            return sampleInitial(1, false);
+        }).thenCompose(second -> {
+            baseline.add(second);
+            return sampleInitial(1, false);
+        }).thenCompose(repeated -> {
+            require(baseline.get(1).equals(repeated), "Second chunk changed after reversed generation order");
+            return sampleInitial(0, false);
+        }).thenCompose(repeated -> {
+            require(baseline.get(0).equals(repeated), "First chunk changed after reversed generation order");
+            return sampleInitial(0, true);
+        }).thenCompose(marker -> {
+            baseline.add(marker);
+            return sampleInitial(1, true);
+        }).thenCompose(marker -> {
+            baseline.add(marker);
+            return sampleInitial(1, true);
+        }).thenCompose(repeated -> {
+            require(baseline.get(3).equals(repeated), "Second marker changed after reversed generation order");
+            return sampleInitial(0, true);
+        }).whenComplete((repeated, failure) -> {
+            if (failure != null) {
+                fail(sender, failure);
+                return;
+            }
+            try {
+                require(baseline.get(2).equals(repeated), "First marker changed after reversed generation order");
+                evidence(sender, "SPAWN_QA_SEEDED chunks=2 markers=2 repeats=2 equipment=true attributes=true");
+            } catch (Throwable error) {
+                fail(sender, error);
+            }
+        });
+    }
+
+    private CompletableFuture<List<String>> sampleInitial(int chunkX, boolean marker) {
+        CompletableFuture<List<String>> result = new CompletableFuture<>();
+        World world = requireWorld();
+        Bukkit.getRegionScheduler().execute(this, world, chunkX, 0, () -> {
+            try {
+                Chunk chunk = world.getChunkAt(chunkX, 0);
+                for (Entity entity : chunk.getEntities()) {
+                    if (entity instanceof LivingEntity && !(entity instanceof Player)) {
+                        entity.remove();
+                    }
+                }
+                for (int x = 0; x < 16; x++) {
+                    for (int z = 0; z < 16; z++) {
+                        chunk.getBlock(x, 64, z).setType(Material.GRASS_BLOCK, false);
+                        for (int y = 65; y <= 68; y++) {
+                            chunk.getBlock(x, y, z).setType(Material.AIR, false);
+                        }
+                    }
+                }
+                RuntimeSpawn spawn = runtimeSpawn(chunk, "seeded");
+                IrisSpawner definition = spawn.environment().data().getSpawnerLoader().load("qa/seeded");
+                require(!definition.canSpawn(spawn.engine(), chunkX, 0), "Ongoing weather/time gate unexpectedly allowed spawning");
+                for (int i = 0; i < 100 + chunkX; i++) {
+                    RNG.r.nextLong();
+                }
+                ambientInvocation.set(true);
+                try {
+                    for (int i = 0; i < 5; i++) {
+                        LivingEntity witness = (LivingEntity) world.spawnEntity(new Location(world, (chunkX << 4) + 8.5, 65, 8.5), EntityType.ZOMBIE);
+                        witness.setCustomName("Population witness");
+                        witness.setAI(false);
+                        witness.setGravity(false);
+                    }
+                } finally {
+                    ambientInvocation.remove();
+                }
+                if (marker) {
+                    invokeInitialMarker(spawn, definition, new IrisPosition((chunkX << 4) + 5, 64, 5));
+                } else {
+                    invokeAmbient(spawn, chunk, true);
+                }
+                List<String> snapshot = new ArrayList<>();
+                for (Entity entity : chunk.getEntities()) {
+                    String name = entity.getCustomName();
+                    if (!(entity instanceof LivingEntity living) || name == null || !name.startsWith("Seeded ")) {
+                        continue;
+                    }
+                    ItemStack hand = living.getEquipment().getItemInMainHand();
+                    ItemStack helmet = living.getEquipment().getHelmet();
+                    require(hand.hasItemMeta() && hand.getItemMeta().hasAttributeModifiers(), "Spawned gear has no authored attributes");
+                    require(helmet != null && helmet.getType() == Material.IRON_HELMET, "Spawned helmet was not authored equipment");
+                    Location at = entity.getLocation();
+                    snapshot.add(entity.getType() + ":" + at.getX() + ":" + at.getY() + ":" + at.getZ()
+                            + ":" + HexFormat.of().formatHex(hand.serializeAsBytes())
+                            + ":" + HexFormat.of().formatHex(helmet.serializeAsBytes()));
+                }
+                require(snapshot.size() >= 2 && snapshot.size() <= 4, "Initial population was blocked by runtime gates or cap: " + snapshot.size());
+                Collections.sort(snapshot);
+                result.complete(List.copyOf(snapshot));
+            } catch (Throwable failure) {
+                result.completeExceptionally(failure);
+            }
+        });
+        return result;
+    }
+
+    private void invokeInitialMarker(RuntimeSpawn spawn, IrisSpawner definition, IrisPosition position) {
+        ambientInvocation.set(true);
+        try (BiomeEnvironment.Scope ignored = spawn.engine().openBiomeEnvironmentScope(spawn.environment())) {
+            Method method = spawn.spawner().getClass().getDeclaredMethod("spawnMarker", IrisPosition.class, IrisSpawner.class, IrisMarker.class, RNG.class, boolean.class);
+            method.setAccessible(true);
+            method.invoke(spawn.spawner(), position, definition, null, EntitySpawnSeed.marker(spawn.engine().getSeedManager().getEntity(), position.getX(), position.getY(), position.getZ()), true);
+        } catch (InvocationTargetException failure) {
+            throw new IllegalStateException("Initial marker spawning failed", failure.getCause());
+        } catch (ReflectiveOperationException failure) {
+            throw new IllegalStateException("Could not invoke initial marker spawning", failure);
+        } finally {
+            ambientInvocation.remove();
+        }
+    }
+
+    private void spawnFrogs(CommandSender sender) {
+        Chunk chunk = requireWorld().getChunkAt(0, 0);
+        RuntimeSpawn spawn = runtimeSpawn(chunk, "frogs");
+        getLogger().info(spawnDiagnostics(spawn, chunk));
+        for (int attempt = 0; attempt < 12; attempt++) {
+            invokeAmbient(spawn, chunk, false);
+            require(count(chunk, EntityType.FROG) <= FROG_CAPACITY, "Frog batch exceeded its category capacity");
+        }
+        require(count(chunk, EntityType.FROG) == FROG_CAPACITY,
+                "Frog ambient category did not fill: " + spawnDiagnostics(spawn, chunk));
+        require(count(chunk, EntityType.ZOMBIE) == 0, "Unexpected zombie before cave phase");
+        verifyPersistence(chunk);
+        evidence(sender, "SPAWN_QA_FROGS frogs=" + count(chunk, EntityType.FROG)
+                + " persistent=true removable=true ambient=true");
+    }
+
+    private void spawnZombies(CommandSender sender) {
+        Chunk chunk = requireWorld().getChunkAt(0, 0);
+        require(count(chunk, EntityType.FROG) == FROG_CAPACITY, "Frogs must fill their category before cave spawning");
+        require(count(chunk, EntityType.ZOMBIE) == 0, "Cave phase already ran");
+        RuntimeSpawn spawn = runtimeSpawn(chunk, "cave-zombies");
+        getLogger().info(spawnDiagnostics(spawn, chunk));
+        invokeAmbient(spawn, chunk, false);
+        firstZombieBatch = count(chunk, EntityType.ZOMBIE);
+        require(firstZombieBatch == ZOMBIE_CAPACITY,
+                "Authored seven-zombie batch was not clamped to capacity two: " + spawnDiagnostics(spawn, chunk));
+        require(count(chunk, EntityType.FROG) == FROG_CAPACITY, "Cave spawning changed the passive population");
+        verifyPersistence(chunk);
+        evidence(sender, "SPAWN_QA_ZOMBIES frogs=" + count(chunk, EntityType.FROG)
+                + " zombies=" + firstZombieBatch + " firstBatch=" + firstZombieBatch + " ambient=true");
+    }
+
+    private void stress(CommandSender sender) {
+        Chunk chunk = requireWorld().getChunkAt(0, 0);
+        RuntimeSpawn spawn = runtimeSpawn(chunk, "cave-zombies");
+        for (int attempt = 0; attempt < 50; attempt++) {
+            invokeAmbient(spawn, chunk, false);
+            require(count(chunk, EntityType.ZOMBIE) == ZOMBIE_CAPACITY, "Saturated zombie category exceeded capacity");
+        }
+        evidence(sender, "SPAWN_QA_STRESS attempts=50 zombies=" + count(chunk, EntityType.ZOMBIE));
+    }
+
+    private void check(CommandSender sender) {
+        Chunk chunk = requireWorld().getChunkAt(0, 0);
+        require(count(chunk, EntityType.FROG) == FROG_CAPACITY, "Passive population differs");
+        require(count(chunk, EntityType.ZOMBIE) == ZOMBIE_CAPACITY, "Hostile population differs");
+        require(firstZombieBatch == ZOMBIE_CAPACITY, "First hostile batch was not pinned");
+        require(chunk.getBlock(8, -47, 8).getType() == Material.CAVE_AIR, "Cave is not real CAVE_AIR");
+        require(chunk.getBlock(8, -47, 8).getLightLevel() == 0, "Cave is not dark");
+        for (Entity entity : chunk.getEntities()) {
+            if (entity.getType() == EntityType.ZOMBIE) {
+                require(entity.getLocation().getY() < -42, "Hostile spawned outside the cave");
+            }
+        }
+        verifyPersistence(chunk);
+        evidence(sender, "SPAWN_QA_RESULT frogs=16 zombies=2 firstBatch=2 persistent=true removable=true caveAir=true light=0");
+    }
+
+    private RuntimeSpawn runtimeSpawn(Chunk chunk, String biomeKey) {
+        try {
+            Engine engine = IrisToolbelt.access(chunk.getWorld()).getEngine();
+            BiomeEnvironment surface = engine.getSurfaceBiomeEnvironment(8, 8);
+            IrisBiome biome = surface.data().getBiomeLoader().load(biomeKey);
+            require(biome != null, "Synthetic biome was not loaded");
+            BiomeEnvironment selected = new BiomeEnvironment(surface.activationId(), biome, surface.region(),
+                    surface.dimension(), surface.data());
+            Object manager = engine.getWorldManager();
+            Field field = manager.getClass().getDeclaredField("entitySpawner");
+            field.setAccessible(true);
+            Object spawner = field.get(manager);
+            Method method = spawner.getClass().getDeclaredMethod("spawnAmbient", Chunk.class, boolean.class, BiomeEnvironment.class);
+            method.setAccessible(true);
+            return new RuntimeSpawn(engine, spawner, method, selected);
+        } catch (ReflectiveOperationException failure) {
+            throw new IllegalStateException("Could not access Iris ambient spawning", failure);
+        }
+    }
+
+    private String spawnDiagnostics(RuntimeSpawn spawn, Chunk chunk) {
+        World world = chunk.getWorld();
+        int floor = world.getHighestBlockYAt(8, 8, HeightMap.OCEAN_FLOOR);
+        int top = world.getHighestBlockYAt(8, 8, HeightMap.WORLD_SURFACE);
+        Map<String, Integer> categories = new TreeMap<>();
+        Map<String, Integer> types = new TreeMap<>();
+        for (Entity entity : chunk.getEntities()) {
+            if (entity instanceof LivingEntity && !(entity instanceof Player)) {
+                categories.merge(BukkitEntityType.of(entity.getType()).spawnCategory(), 1, Integer::sum);
+                types.merge(entity.getType().name(), 1, Integer::sum);
+            }
+        }
+        StringBuilder diagnostics = new StringBuilder("SPAWN_QA_DIAGNOSTICS frogs=")
+                .append(count(chunk, EntityType.FROG)).append(" zombies=").append(count(chunk, EntityType.ZOMBIE))
+                .append(" categories=").append(categories).append(" types=").append(types)
+                .append(" loadLevel=").append(chunk.getLoadLevel())
+                .append(" spawnMobs=").append(world.getGameRuleValue(GameRules.SPAWN_MOBS))
+                .append(" animals=").append(world.getAllowAnimals()).append(" monsters=").append(world.getAllowMonsters())
+                .append(" floor=").append(floor).append(" top=").append(top)
+                .append(" support=").append(world.getBlockAt(8, top, 8).getType())
+                .append(" above=").append(world.getBlockAt(8, top + 1, 8).getType())
+                .append(" light=").append(world.getBlockAt(8, top + 1, 8).getLightLevel())
+                .append(" events=").append(ambientEvents).append(" cancelled=").append(cancelledAmbientEvents);
+        for (String key : spawn.environment().biome().getEntitySpawners()) {
+            IrisSpawner spawner = spawn.environment().data().getSpawnerLoader().load(key);
+            if (spawner == null) {
+                diagnostics.append(" spawner=").append(key).append(":missing");
+                continue;
+            }
+            diagnostics.append(" spawner=").append(key).append(" canSpawn=")
+                    .append(spawner.canSpawn(spawn.engine(), chunk.getX(), chunk.getZ()))
+                    .append(" excluded=").append(spawner.isCompatExcluded())
+                    .append(" group=").append(spawner.getGroup()).append(" capacity=").append(spawner.getMaxEntitiesPerChunk());
+            for (IrisEntitySpawn entry : spawner.getSpawns()) {
+                IrisEntity entity = entry.getRealEntity(spawn.engine());
+                diagnostics.append(" entity=").append(entry.getEntity());
+                if (entity == null) {
+                    diagnostics.append(":missing");
+                    continue;
+                }
+                diagnostics.append(" type=").append(entity.getBukkitType()).append(" category=").append(entity.spawnCategory())
+                        .append(" surface=").append(entity.getSurface())
+                        .append(" supportMatches=").append(entity.getSurface().matches(world.getBlockAt(8, top, 8)))
+                        .append(" bounds=").append(BukkitPlatform.entityBoundingBox(entity.getBukkitType()));
+            }
+        }
+        return diagnostics.toString();
+    }
+
+    private void invokeAmbient(RuntimeSpawn spawn, Chunk chunk, boolean initial) {
+        ambientInvocation.set(true);
+        try (BiomeEnvironment.Scope ignored = spawn.engine().openBiomeEnvironmentScope(spawn.environment())) {
+            spawn.method().invoke(spawn.spawner(), chunk, initial, spawn.environment());
+        } catch (InvocationTargetException failure) {
+            throw new IllegalStateException("Iris ambient spawning failed", failure.getCause());
+        } catch (ReflectiveOperationException failure) {
+            throw new IllegalStateException("Could not invoke Iris ambient spawning", failure);
+        } finally {
+            ambientInvocation.remove();
+        }
+    }
+
+    private int count(Chunk chunk, EntityType type) {
+        int count = 0;
+        for (Entity entity : chunk.getEntities()) {
+            if (entity.getType() == type) {
+                count++;
+            }
+        }
+        return count;
+    }
+
+    private void verifyPersistence(Chunk chunk) {
+        for (Entity entity : chunk.getEntities()) {
+            if (entity.getType() == EntityType.FROG || entity.getType() == EntityType.ZOMBIE) {
+                require(entity.isPersistent(), "Ambient entity stopped participating in chunk saves");
+                require(entity instanceof LivingEntity living && living.getRemoveWhenFarAway(),
+                        "Ambient entity has distance despawning disabled");
+            }
+        }
+    }
+
+    private void view(CommandSender sender, double y) {
+        teleport(sender, requireWorld(), y, "SPAWN_QA_VIEW y=" + (int) y);
+    }
+
+    private void teleport(CommandSender sender, World world, double y, String message) {
+        if (!(sender instanceof Player player)) {
+            throw new IllegalArgumentException("Viewing requires a player");
+        }
+        player.getScheduler().run(this, task -> {
+            player.setGameMode(GameMode.CREATIVE);
+            player.setAllowFlight(true);
+            player.setFlying(true);
+            player.teleportAsync(new Location(world, 40.5D, y, 8.5D)).whenComplete((success, failure) -> {
+                if (failure != null || !Boolean.TRUE.equals(success)) {
+                    fail(sender, failure == null ? new IllegalStateException("Fixture teleport failed") : failure);
+                } else {
+                    notifySender(sender, message);
+                }
+            });
+        }, null);
+    }
+
+    private World requireWorld() {
+        World world = Bukkit.getWorld(WORLD_KEY);
+        require(ready && world != null, "Run setup before a spawning phase");
+        return world;
+    }
+
+    private void runRegion(CommandSender sender, Runnable operation) {
+        World world = requireWorld();
+        Bukkit.getRegionScheduler().execute(this, world, 0, 0, () -> {
+            try {
+                operation.run();
+            } catch (Throwable failure) {
+                fail(sender, failure);
+            }
+        });
+    }
+
+    private void evidence(CommandSender sender, String message) {
+        getLogger().info(message);
+        notifySender(sender, message);
+    }
+
+    private void notifySender(CommandSender sender, String message) {
+        if (sender instanceof Player player) {
+            player.getScheduler().run(this, task -> player.sendMessage(message), null);
+        } else {
+            sender.sendMessage(message);
+        }
+    }
+
+    private void fail(CommandSender sender, Throwable failure) {
+        getLogger().log(Level.SEVERE, "Spawning acceptance failed", failure);
+        notifySender(sender, "SPAWN_QA_FAILED " + failure.getMessage());
+    }
+
+    private static void require(boolean condition, String message) {
+        if (!condition) {
+            throw new IllegalStateException(message);
+        }
+    }
+
+    private record CompletionRun(Engine engine, Object maintenance, Method run, Field pending, Runnable callback, AtomicInteger callbacks) {
+    }
+
+    private record RuntimeSpawn(Engine engine, Object spawner, Method method, BiomeEnvironment environment) {
+    }
+}
@@ -0,0 +1,26 @@
+{
+  "name": "Cave Zombies",
+  "derivative": "minecraft:plains",
+  "vanillaDerivative": "minecraft:plains",
+  "layers": [
+    {
+      "minHeight": 1,
+      "maxHeight": 1,
+      "palette": [
+        {
+          "block": "minecraft:grass_block"
+        }
+      ]
+    }
+  ],
+  "generators": [
+    {
+      "generator": "flat",
+      "min": 64,
+      "max": 64
+    }
+  ],
+  "entitySpawners": [
+    "qa/cave-zombies"
+  ]
+}
@@ -0,0 +1,26 @@
+{
+  "name": "Frogs",
+  "derivative": "minecraft:plains",
+  "vanillaDerivative": "minecraft:plains",
+  "layers": [
+    {
+      "minHeight": 1,
+      "maxHeight": 1,
+      "palette": [
+        {
+          "block": "minecraft:grass_block"
+        }
+      ]
+    }
+  ],
+  "generators": [
+    {
+      "generator": "flat",
+      "min": 64,
+      "max": 64
+    }
+  ],
+  "entitySpawners": [
+    "qa/frogs"
+  ]
+}
@@ -0,0 +1,26 @@
+{
+  "name": "Seeded population",
+  "derivative": "minecraft:plains",
+  "vanillaDerivative": "minecraft:plains",
+  "layers": [
+    {
+      "minHeight": 1,
+      "maxHeight": 1,
+      "palette": [
+        {
+          "block": "minecraft:grass_block"
+        }
+      ]
+    }
+  ],
+  "generators": [
+    {
+      "generator": "flat",
+      "min": 64,
+      "max": 64
+    }
+  ],
+  "entitySpawners": [
+    "qa/seeded"
+  ]
+}
@@ -0,0 +1,28 @@
+{
+  "name": "Spawn QA",
+  "version": 1,
+  "mode": {
+    "type": "OVERWORLD"
+  },
+  "regions": [
+    "flat"
+  ],
+  "focusRegion": "flat",
+  "focus": "frogs",
+  "landChance": 1,
+  "environment": "NORMAL",
+  "dimensionHeight": {
+    "min": -64,
+    "max": 320
+  },
+  "logicalHeight": 384,
+  "fluidHeight": 0,
+  "bedrock": false,
+  "rockPalette": {
+    "palette": [
+      {
+        "block": "minecraft:stone"
+      }
+    ]
+  }
+}
@@ -0,0 +1,8 @@
+{
+  "type": "minecraft:frog",
+  "reason": "NATURAL",
+  "surface": "LAND",
+  "ai": false,
+  "aware": false,
+  "gravity": false
+}
@@ -0,0 +1,29 @@
+{
+  "type": "minecraft:husk",
+  "reason": "NATURAL",
+  "surface": "LAND",
+  "ai": false,
+  "aware": false,
+  "gravity": false,
+  "customName": "Seeded husk",
+  "invulnerable": true,
+  "helmet": {
+    "type": "IRON_HELMET",
+    "minDurability": 0.1,
+    "maxDurability": 0.9
+  },
+  "mainHand": {
+    "type": "IRON_SWORD",
+    "minDurability": 0.1,
+    "maxDurability": 0.9,
+    "attributes": [
+      {
+        "name": "seeded_damage",
+        "attribute": "minecraft:attack_damage",
+        "minAmount": 1.25,
+        "maxAmount": 6.75,
+        "chance": 1
+      }
+    ]
+  }
+}
@@ -0,0 +1,29 @@
+{
+  "type": "minecraft:zombie",
+  "reason": "NATURAL",
+  "surface": "LAND",
+  "ai": false,
+  "aware": false,
+  "gravity": false,
+  "customName": "Seeded zombie",
+  "invulnerable": true,
+  "helmet": {
+    "type": "IRON_HELMET",
+    "minDurability": 0.1,
+    "maxDurability": 0.9
+  },
+  "mainHand": {
+    "type": "IRON_SWORD",
+    "minDurability": 0.1,
+    "maxDurability": 0.9,
+    "attributes": [
+      {
+        "name": "seeded_damage",
+        "attribute": "minecraft:attack_damage",
+        "minAmount": 1.25,
+        "maxAmount": 6.75,
+        "chance": 1
+      }
+    ]
+  }
+}
@@ -0,0 +1,8 @@
+{
+  "type": "minecraft:zombie",
+  "reason": "NATURAL",
+  "surface": "LAND",
+  "ai": false,
+  "aware": false,
+  "gravity": false
+}
@@ -0,0 +1,15 @@
+{
+  "interpolator": {
+    "function": "NONE",
+    "horizontalScale": 1
+  },
+  "seed": 310,
+  "composite": [
+    {
+      "seed": 310,
+      "style": {
+        "style": "FLAT"
+      }
+    }
+  ]
+}
@@ -0,0 +1,12 @@
+{
+  "name": "Flat",
+  "landBiomes": [
+    "frogs"
+  ],
+  "seaBiomes": [
+    "frogs"
+  ],
+  "shoreBiomes": [
+    "frogs"
+  ]
+}
@@ -0,0 +1,16 @@
+{
+  "group": "CAVE",
+  "maxEntitiesPerChunk": 2,
+  "allowedLightLevels": {
+    "min": 0,
+    "max": 0
+  },
+  "spawns": [
+    {
+      "entity": "qa/zombie",
+      "rarity": 1,
+      "minSpawns": 7,
+      "maxSpawns": 7
+    }
+  ]
+}
@@ -0,0 +1,12 @@
+{
+  "group": "NORMAL",
+  "maxEntitiesPerChunk": 16,
+  "spawns": [
+    {
+      "entity": "qa/frog",
+      "rarity": 1,
+      "minSpawns": 7,
+      "maxSpawns": 7
+    }
+  ]
+}
@@ -0,0 +1,33 @@
+{
+  "group": "NORMAL",
+  "maxEntitiesPerChunk": 4,
+  "allowedLightLevels": {
+    "min": 0,
+    "max": 0
+  },
+  "weather": "DOWNFALL",
+  "timeBlock": {
+    "startHour": 20,
+    "endHour": 3
+  },
+  "maximumRate": {
+    "amount": 1,
+    "per": {
+      "days": 1
+    }
+  },
+  "initialSpawns": [
+    {
+      "entity": "qa/seeded-zombie",
+      "rarity": 1,
+      "minSpawns": 2,
+      "maxSpawns": 4
+    },
+    {
+      "entity": "qa/seeded-husk",
+      "rarity": 2,
+      "minSpawns": 2,
+      "maxSpawns": 4
+    }
+  ]
+}
@@ -0,0 +1,42 @@
+export default {
+  name: 'iris-natural-spawning',
+  description: 'Observe category-limited Iris ambient frogs and cave zombies on Folia.',
+  async run(context) {
+    const wait = (predicate, label, timeoutMs = 30000) => context.waitUntil(predicate, { label, timeoutMs, intervalMs: 100 })
+    const command = async (operation, expected, timeoutMs = 30000) => {
+      const response = await context.command(`/irisspawnqa ${operation}`, /SPAWN_QA_[A-Z]+(?:\s|$)/, timeoutMs)
+      context.expect(response.includes(expected) && !response.includes('SPAWN_QA_FAILED'), response)
+      return response
+    }
+    const entities = name => Object.values(context.bot.entities).filter(entity => entity.name === name
+      && entity.position.x >= 0 && entity.position.x < 16 && entity.position.z >= 0 && entity.position.z < 16)
+    await context.step('prepare the synthetic Iris world and dark cave', async () => {
+      await command('setup', 'SPAWN_QA_SETUP world=iris:spawn_qa seed=78264193', 180000)
+      await wait(() => Math.abs(context.bot.entity.position.y - 67) < 1, 'Fixture world teleport')
+    })
+    await context.step('fill the passive category through real Iris ambient spawning', async () => {
+      await command('frogs', 'SPAWN_QA_FROGS frogs=16 persistent=true removable=true ambient=true', 60000)
+      await wait(() => entities('frog').length === 16, 'All sixteen ambient frogs became visible')
+      context.report.irisNaturalSpawning = { visibleFrogs: entities('frog').length }
+    })
+    await context.step('spawn an authored seven-zombie batch with capacity two despite existing frogs', async () => {
+      await command('zombies', 'SPAWN_QA_ZOMBIES frogs=16 zombies=2 firstBatch=2 ambient=true', 60000)
+      await command('cave', 'SPAWN_QA_VIEW y=-46')
+      await wait(() => Math.abs(context.bot.entity.position.y + 46) < 1, 'Underground fixture teleport')
+      await wait(() => context.bot.blockAt(context.bot.entity.position.clone().set(8, -47, 8))?.name === 'cave_air', 'Live cave_air block reached the client')
+      await wait(() => entities('zombie').length === 2, 'Both ambient cave zombies became visible')
+      context.expect(entities('zombie').every(entity => entity.position.y < -42), 'Zombies were not inside the underground chamber')
+      context.report.irisNaturalSpawning.visibleZombies = entities('zombie').length
+      context.report.irisNaturalSpawning.caveAir = true
+    })
+    await context.step('repeat fifty ambient attempts without exceeding the hostile capacity', async () => {
+      await command('stress', 'SPAWN_QA_STRESS attempts=50 zombies=2', 60000)
+      await command('check', 'SPAWN_QA_RESULT frogs=16 zombies=2 firstBatch=2 persistent=true removable=true caveAir=true light=0', 30000)
+      context.expect(entities('zombie').length === 2, 'Client observed a hostile capacity overflow')
+      context.report.irisNaturalSpawning.saturatedAttempts = 50
+      context.report.irisNaturalSpawning.firstHostileBatch = 2
+      context.report.irisNaturalSpawning.removeWhenFarAwayAllowed = true
+      context.report.irisNaturalSpawning.chunkSaving = true
+    })
+  }
+}
@@ -0,0 +1,32 @@
+{
+  "name": "Flat",
+  "derivative": "minecraft:plains",
+  "vanillaDerivative": "minecraft:plains",
+  "layers": [
+    {
+      "minHeight": 1,
+      "maxHeight": 1,
+      "palette": [
+        {
+          "block": "minecraft:lime_wool"
+        }
+      ]
+    },
+    {
+      "minHeight": 384,
+      "maxHeight": 384,
+      "palette": [
+        {
+          "block": "minecraft:green_concrete"
+        }
+      ]
+    }
+  ],
+  "generators": [
+    {
+      "generator": "flat",
+      "min": 64,
+      "max": 96
+    }
+  ]
+}
				`@@ -0,0 +1 @@`
				`rootProject.name = 'iris-craftengine-native-fixture'`
				`@@ -0,0 +1 @@`
				`rootProject.name = 'iris-natural-spawning-fixture'`