[Hafeok]

Completes: #230

What this changes, and why

Step 0 of the chain-builds work. This is the ADR for #230, with the maintainer's review of 2026-11-11 folded in.

It is stacked on #261 (which stacks on #260 and #259), so it lands after them. Its own commits are the last two: 743af6a and 5a4850b. It stacks there for two reasons:

• its note on ADR 0102 follows A release descriptor's date follows its digests: release.cs --sbom, and land.cs's three days (#248) #261's amendment;

• step 1 (Landing trains: several approved heads land in one run #277) extends land.cs: closing trailers checked before a push and after main moves (#209) #260's closing-trailer check.

• docs/adr/0243-chain-builds-ahead-of-main.md. This is ADR proposal: chain builds ahead of main (feature tree, chain builds, path-encoded versions) #230's text with:

  • the four open questions settled: a reserved header byte as the marker; stable tags cut by a workflow on request; .nupkg files and SBOMs only; https://w3id.org/varve/chain#;
  • the review's seven additions: landing trains, a pinned gate, bounded trial merges, "stable" implies accepted, no squash for chain branches, ADR numbers at landing as step 6, and chain branches opt-in.

  Each settled question and addition is marked settled in review, 2026-11-11. A table, Differences from ADR proposal: chain builds ahead of main (feature tree, chain builds, path-encoded versions) #230, lists every place where the review's ruling replaces the issue's text.

• docs/decisions/chain-builds-ahead-of-main.md: thirteen keys, all unaccepted (ADR 0066). This session is a cloud session, not the delegate (ADR 0239).

• Dated amendments, unaccepted:

  • 0088: main moves only by fast-forward; a merge commit made on a branch counts as an ordinary commit; a chain branch never lands by squash; a train is one checked head.
  • 0102: chain builds are outside a release's scope; the release workflow refuses chain/*; a release may ride last in a train.

• docs/adr/README.md rows, and the traceability record.

Number 0243. Open pull requests already hold 0240 (#268), 0241 (#259, and also #264, filed as #278) and 0242 (#267).

What was measured

• eng/ci.cs --only decision-sets: pass (220 sets, 1,528 decisions).
• eng/issue-refs.cs: 13 commits reference an issue, and every closing keyword is a trailer.
• eng/dco.cs: every commit is signed off.
• No code changed, so the test counts are unchanged.

What was found

• ADR 0241 is taken twice, by AGENTS.md: issues are the work log; ADR 0241, a commit message never names a model (#257) #259 and by Memory bounds for writing, checkpointing and reopening: a dataset written under a limit reopens under it (#227) #264. Filed as ADR 0241 is taken twice by open pull requests (#259 and #264) #278.
• The issue-log practice the session prompt cites is not on main. It is in AGENTS.md: issues are the work log; ADR 0241, a commit message never names a model (#257) #259, which this stacks on. The session followed it.

What is left

• Steps 1 to 6. Step 1 is Landing trains: several approved heads land in one run #277, whose plan is posted there. Issues for steps 2 to 6 are opened when each starts.
• Questions for the maintainer (also on ADR proposal: chain builds ahead of main (feature tree, chain builds, path-encoded versions) #230):
  1. This closes ADR proposal: chain builds ahead of main (feature tree, chain builds, path-encoded versions) #230 while the rulings are still unaccepted, and steps 1 to 6 cite them as CS0618 until you accept them. Is that what you want, or should acceptance come on this pull request first?
  2. Do you want to overrule the namespace before step 2?
  3. Two additions are mine; keep or strike them: GitHub's merge queue as a rejected alternative, and a revisit condition on trains.

Head: 5a4850b7.

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Checklist

• Issue referenced: Refs on each commit, and Closes #230 on the ADR's commit.
• ADR cited: ADR 0243 filed unaccepted; 0088 and 0102 amended, add-only.
• Specification updated, or n/a: n/a. docs/spec/storage-format.md changes in step 3.
• API baseline updated, or n/a: n/a.
• Conformance baseline updated, or n/a: n/a.
• Tests: n/a. No code changed.
• A new gate's failure path was proven by running it: n/a. No gate added.
• Signed off: by the commit-msg hook.
• A traceability record exists: docs/traceability/2026-11-11-issue-230-chain-builds-ahead-of-main.md.
• dotnet run eng/ci.cs passes locally: only the process gates were run. Red on CS0618 is not expected, because nothing cites the new keys yet.

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Generated by Claude Code

[Hafeok]

The maintainer's decisions of 2026-11-11, recorded

1. The rulings are accepted on this pull request before it lands, and ADR proposal: chain builds ahead of main (feature tree, chain builds, path-encoded versions) #230 closes with it. The Closes #230 trailer is on 743af6a. The accepted-by lines are yours, or your delegate's on your machine (ADR 0239); this cloud session does not write them. Once they are added, the thirteen keys of chain-builds-ahead-of-main stop being CS0618 in the steps that cite them.
2. The namespace stays https://w3id.org/varve/chain#.
3. Both of the session's additions stay: GitHub's merge queue as a rejected alternative, and the revisit condition on trains.
4. A one-member train stays refused, and a failed train whose shorter form has one member prints the plain landing command (Landing trains: land.cs --train, and agent review admits a train of approved heads (#277) #281).

New head d6ffddca8f50. It adds one bullet to ADR 0243 point 10: the merge is pinned. land.cs and agent review run git merge-tree under the same settings; a tree mismatch from a different git refuses the train; a local info/attributes refuses it. The rest of the ADR is unchanged.

The full eng/ci.cs is running on this head; results to follow.

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Generated by Claude Code

[Hafeok]

dotnet run eng/ci.cs at d6ffddca8f50: all 66 jobs pass, exit 0, 18 min 6 s

Run in a fresh worktree of the head, with the W3C submodules initialised, on a 4-core Linux container. This is the whole pipeline as eng/ci.cs defines it: no --only, nothing skipped.

• Process gates:
  • issue-refs: 14 commits reference an issue, and every closing keyword is a trailer;
  • dco: 14 commits checked, 3 merges skipped;
  • decision-sets, register, licence-headers, banned-symbols, required-checks and release-pending pass.
• Fixtures: land-fixtures, agent-review-tamper and every other fixture job pass.
• Build: restore, build (warnings as errors) and build-benchmarks pass.
• Tests: all 29 test-* jobs pass. The slowest is test-store, at 328 s.
• Ratchet: conformance passes.
• Packaging: pack and decision-report pass.

Red on CS0618 is not expected: nothing cites the new keys yet. This PR changes no test project, so the test counts are main's.

Not run here: the CI-only legs (Windows, Native AOT, browser WASM, the auth and container legs). Those are GitHub's.

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Generated by Claude Code