docs/standards/mcp/modules/versioning_and_changelog.json

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  "module": "versioning_and_changelog",
  "content": {
    "path": "versioning_and_changelog",
    "docstring": "# Versioning & Changelog\n\n## Summary\n\nEvery Aetos artifact — library, service, or site — is versioned with\n[Semantic Versioning](https://semver.org/spec/v2.0.0.html) and documents its\nreleases in a [Keep a Changelog](https://keepachangelog.com/en/1.1.0/) file.\nThe **version file is the source of truth**, the **git tag must equal it**, and\na Drone guard enforces that equality before anything is published. Releases are\ncut manually; a tag is what triggers the pipeline.\n\nThis page pairs with [10 – Drone Pipelines](10_drone_pipelines.md): the version\nand tag contract is exactly what those two CI shapes consume.\n\n---\n\n## The version contract\n\n| Artifact | Source of truth | Notes |\n|----------|-----------------|-------|\n| Library (PyPI package) | `version` in `pyproject.toml` | `check-version` also reads it to skip duplicates |\n| Service / site (Docker) | `VERSION` file at the repo root | one line, `x.y.z` |\n\nRules:\n\n1. **One version per repository.** No per-module versions.\n2. **Tag = version.** The git tag is bare SemVer (`0.0.6`), no `v` prefix, and\n   it MUST match the version file byte-for-byte. The Drone guard fails the\n   build otherwise — this is what stops a tag from silently publishing nothing.\n3. **A release is a tag, created after the change is merged.** The version bump\n   and the changelog promotion travel inside the merge request (MR); the tag is\n   added on the merged commit and pushed. See [Tagging strategy](#tagging-strategy-mr-based).\n4. **Never reuse a tag.** If a release is wrong, cut a new patch version.\n\n### Pre-1.0 (0.y.z)\n\nWhile a package is `0.y.z`, **`0.y` is treated as the major line**:\n\n- breaking change → `0.(y+1).0`\n- new feature → `0.y.(z+1)`\n- bug fix → `0.y.(z+1)`\n\nOnce a package reaches `1.0.0`, normal SemVer applies. Do not ship `1.0.0`\nuntil the public API is considered stable.\n\n---\n\n## The changelog\n\n`CHANGELOG.md` at the repo root, in Keep a Changelog form. It always has exactly\none open `[Unreleased]` section with the change categories that apply:\n\n```markdown\n## [Unreleased]\n\n### Added\n### Changed\n### Deprecated\n### Removed\n### Fixed\n### Security\n```\n\nOn release you **promote** it — never delete history:\n\n```markdown\n## [0.0.6] - 2026-03-07\n\n### Added\n- ...\n```\n\nand add a link reference at the bottom:\n\n```markdown\n[Unreleased]: https://git.aetoskia.com/aetos/<repo>/compare/0.0.6...HEAD\n[0.0.6]: https://git.aetoskia.com/aetos/<repo>/compare/0.0.5...0.0.6\n```\n\nConventions:\n\n- Write entries for humans: one line each, imperative, referencing the user\n  impact, not the commit hash.\n- Categories: **Added**, **Changed**, **Deprecated**, **Removed**, **Fixed**,\n  **Security**. Omit empty categories.\n- Security fixes get their own entry even if the change is otherwise a bug fix.\n- The `[Unreleased]` heading is never renamed; copy its content into the new\n  version heading and clear it.\n\n---\n\n## Tagging strategy (MR-based)\n\nThe release version is known while the change is still a merge request, so the\nbump travels with the change and only the tag is added afterwards:\n\n1. **In the MR** — set the intended release version: `version` in\n   `pyproject.toml` (or the `VERSION` file) to `x.y.z`, and promote the\n   changelog (below). Changelog entries and link references name the\n   **version/tag**, never a commit id.\n2. **Merge or squash** the MR into `main`.\n3. **Create the tag** `x.y.z` on the resulting commit (the merge/squash commit).\n4. **Push the tag** (`git push origin x.y.z`) — Drone builds the release.\n\nBecause the version bump is inside the tagged commit, the guard's\n`tag == version` check can only fail if the wrong commit was tagged.\n\n### Agent-assisted tagging\n\nThe agent neither authors nor merges the MR, and never tags before the merge.\nAfter the user confirms the MR is merged/squashed and says to proceed:\n\n1. **Wait** for that explicit go-ahead.\n2. Find the commit that introduced the version bump:\n   - packages:\n     `git log -S 'version = \"x.y.z\"' -n 1 --format='%H %s' -- pyproject.toml`\n   - services:\n     `git log -S 'x.y.z' -n 1 --format='%H %s' -- VERSION`\n3. Confirm that commit's version file equals `x.y.z`, then tag **only** that\n   commit, lightweight and bare: `git tag x.y.z <sha>`.\n4. **Do not push.** Ask the user to push the tag: `git push origin x.y.z`.\n\n---\n\n## Release checklist\n\n1. Confirm the quality gate is green and `main` is up to date.\n2. In the MR: move every `[Unreleased]` entry under the new version heading with\n   the target date (`## [x.y.z] - YYYY-MM-DD`); restore an empty `[Unreleased]`\n   on top.\n3. In the MR: add the two compare-link references at the bottom of the\n   changelog, naming the version/tag (never a commit id).\n4. In the MR: set the version file — `pyproject.toml` (`version = \"x.y.z\"`) or\n   `VERSION` — to the intended release version.\n5. Merge or squash the MR into `main`.\n6. Create the tag on the resulting commit: lightweight `git tag x.y.z`.\n7. Push the tag (`git push origin x.y.z`). Watch Drone: Type A publishes the\n   wheel/sdist, Type B builds and deploys the image; both first assert\n   `tag == version`.\n8. Do not reuse the tag if the run fails — fix and cut `x.y.(z+1)`.\n\n---\n\n## Why the guard matters\n\nThe version file and the tag are two facts that must agree; nothing in git\nenforces that by itself. A mismatch is not a theoretical risk — a package can be\ntagged `0.0.2` while its `pyproject.toml` still says `0.0.1`, and the publish\nstep (which compares the **file** against the index) then skips the build\nentirely, so `0.0.2` never reaches the index while looking like a release. The\nDrone guard turns that silent no-op into a hard failure.\n\n---\n\n## Related\n\n- [10 – Drone Pipelines](10_drone_pipelines.md) · [15 – Repository Inventory](15_repository_inventory.md) · [01 – Build Recipe](01_build_recipe.md) · [13 – Library Registry](13_library_registry.md)\n",
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