agent: builder model: opus max_turns: 70 budget_usd: 14 —
Score: self-hosting lane, row GR of docs/selfhosting-plan.md. GR was built (b070adb9, report docs/briefs/gr-grammar-run.md.report.md) and reverted (0fbe3d6b) because lowered/project_members.rs drifted (TrustedMap to HashMap). The first re-land run (report of 8eac868c) showed the drift is GR’s, and right: see Re-run. The gate turns undeclared drift red (gate_lowered_drift), so the changed project_members.rs is committed with the move. Small: S=1, C~1 M.
Facts: Where things live, Traps already met, Moving Rust into Nikaia, Commands
Shape: faithful (the reviewed code of b070adb9; no Convert: line: nothing new is converted)
git log --oneline -1 0fbe3d6b is the revert and crates/nikaia-std/src/tools/grammar_run.nika does not exist.cargo build --profile fast -p nikaia first, so lower-std runs on a binary of HEAD (the b15 lesson: a stale target/fast/nikaia rewrites lowered files).git revert --no-commit 0fbe3d6b. Checked on origin/develop c5873d3f: grammar_run.nika, lowered/grammar_run.rs and grammar_run.rs apply; lowered.rs, docs/selfhosting-plan.md and scripts/self_hosting.py conflict. Resolve them: keep today’s side and add GR’s lines (the plan row GR as built, its self_hosting.py entry); lowered.rs comes from lower-std, not by hand.lower-std (twice: fixpoint), then git status --short crates/nikaia-std/src/tools/lowered/: only grammar_run.rs, lowered.rs and project_members.rs may differ from HEAD, and project_members.rs only in its fs::Path-keyed maps and sets going from collections::TrustedMap/TrustedSet to the keyed collections::HashMap/HashSet (about 14 lines: seen, here, at_of, renames_in’s here). That change is right and is committed with the move (see Re-run below). Any other lowered file differing, or project_members.rs differing otherwise, is Found: with the diff’s first lines, and stops the brief.cargo check --profile fast -p nikaia-std --features compiler --message-format short; a rustc error in lowered/grammar_run.rs is a lowering defect: stop, Found: with the lowered line.it filters grammar_at_build_time dsl_grammar build_time comptime (b070adb9 ran 115), and nikaia test --project tests/compiler --both-settings on the tests whose names contain grammar, comptime, sysroot, lowered (by name).
Commit grammar run: the parser's build and run move into Nikaia (GR, again after 0fbe3d6b), Part: #125; Body: b070adb9’s body, plus one sentence that b15 cleared the drift the revert named.Body:)The unchanged-file check reuses sysroot_holds (sysroot_cache.nika), since String? == String is NK1102; process::run throws on output that is not UTF-8 where Rust read it lossily; {error} is an io::IoError’s text.
A conflict outside the three files above; a lowered file other than GR’s and project_members.rs drifts; a rustc error where a keyed and a trusted map meet (a TrustedMap handed where HashMap is written, or back): that is the per-file map plan (contracts/trust.rs trusted_maps) disagreeing with ADR-010 D9’s classes, Found: with the rustc line; an error in another agent’s file.
blocked)The first run resolved the revert and saved it: start with git apply docs/briefs/gr2-grammar-run-reland.wip.patch instead of step 1 (checked: it applies to 8eac868c; it leaves lowered.rs out, which comes from lower-std). Then steps 2-4.
Why project_members.rs changes, decided by ADR-010 (no new decision): grammar_run.nika calls process::run, whose result the ledger marks provenance = "untrusted" (std.contracts), the first untrusted source in the tools package. Until now the package read none, so trust.rs join made every map in it fast. With one untrusted source a map is fast only where trusted_maps follows its keys to a trusted source; the fs::Path keys of project_members.nika come through ProjectMembersHost methods, a trait, which D9 point 5 makes a barrier, so those maps are keyed. That is D9’s stated cost (“one untrusted use slows every private map its values share a position with”); per-file trust and a toolchain exemption are both rejected there. Do not mark the process output trusted and do not touch trust.rs. Say this in one sentence of Body:.
Not yours, never stage: every file git status shows modified or untracked at your start (today crates/nikaia/src/sysroot.rs, the rs2nika ledgers and many docs/briefs/* files among them), and every docs/briefs/* file except your report. lower-std also rewrites runtime/lowered.rs from the uncommitted sysroot.rs: restore that file by name (git checkout -- crates/nikaia-std/src/runtime/lowered.rs only if HEAD’s version is what you started with), never stage it.
docs/builder-facts.md first. develop in the main checkout; git status at start: other agents’ uncommitted files are not yours, never touch or stage them.git add <files> only (scripts/commit.nika -- REPORT does it); commit locally after each step and never push: the driver runs the complete suite and pushes (.claude/agents/builder.md, Cheap checks only; owner, 2026-10-31).cargo build --profile fast -p nikaia, lower-std and its fixpoint when a tools/*.nika changed, cargo fmt, cargo clippy --all-targets -- -D warnings, scripts/pre-push-check.sh, the tests the brief names and the ones your change touches. No gate.nika.CHANGELOG.md, badges; no new NK code. New tests in Nikaia only; never the full suite. No foreground sleep, no polling; scripts in files.std or the toolchain lacks stops the work: no code around it unless an ADR or Part I-III refuses it (name it). Else Result: blocked, Found: gap + probe, Needs: architect decision (CLAUDE.md, A missing form stops the work).NIKAIA_CACHE_LIMIT=2G; at most two clones with target/ in the machine; delete your own clone’s target/ and target/release/nikaia-scratch at the end; report GB freed.Result: partial with what you ruled out, the probe, and the suspected file and function (.claude/agents/builder.md).target/fast/nikaia run scripts/commit.nika -- REPORT, which writes Pushed: local <sha> into it. A report without a Pushed: line, or with a placeholder left in (TC, DISK), is not done and cuts the batch (k3a1 2026-10-29: Result: done, nothing committed)./home/user/Nikaia/docs/briefs/gr2-grammar-run-reland.md.report.md)Fields of docs/architect.md, Briefs and reports: Result: done|noop|partial|blocked (the bare word alone on that line: Result: done, never a summary after it, which cuts the batch, b869a 2026-10-27; Owner: is a question for the owner or none, never a role), Files, Commit, Body (optional, one paragraph for the commit message), Fixes, Pushed, Tests, Gate (green|red), Deviation, Found, Needs, Changelog, Owner, Disk freed, and for a move Rs2nika: (the kept N of M lines of rs2nika --score, then the three costliest hand edits; none for a task that moves no Rust, none (redesign) for a brief with Shape: redesign and no Convert: line). none where nothing, and then the bare word: Deviation: none (a note) cuts the batch (batch.nika compares exactly); a note goes into the commit message. Found: is only for a defect outside your change (it cuts the batch); a process event such as another session resetting or rewriting your files is no Found:, it goes under Needs: (m3a 2026-10-28); a converter draft that came out wrong is no Found:, it is one of the costliest edits under Rs2nika:, which the converter lane reads (e12-4b 2026-10-27); how you solved your own step goes into the commit message. Deviation: is only a step of the brief built otherwise than written or not built (a choice the brief left to you, such as keep what X needs and say so, is no deviation: it goes into the commit message; nor is building two steps in one commit when every step is built, e12-3a 2026-10-27, nor a step another commit on develop already built, shown by your test failing with that commit’s change reverted, b889 2026-10-27: name the commit in Body:, nor a test’s expected .stdout/.stderr taken from what the program really prints where the brief’s sketch of it was short or wrong, b934 2026-10-29: say so in Body:, nor a lowering that follows the ADR governing it where the brief’s expected lowering contradicts that ADR, b933 2026-10-29: name the ADR in Body:, nor a lowering other than the brief’s where rustc cannot take the brief’s, b1029 2026-10-31: say why in Body:, nor re-keying an allow-list entry (KNOWN) whose hash changed for the same program and the same reason, b-fixforward-sweep2 2026-10-28: say so in Body:, nor an existing test’s expected .stdout/.stderr updated because your change rightly changes the message it prints, b1012b 2026-10-31: name the test in Body:); how you verified (e.g. a test not run against the unfixed compiler) goes under Tests:. A noop says why under Tests: (what was probed), not under Deviation:. Final answer, one line: done <sha>, report <path> (or BLOCKED: ... / PUSH REJECTED ...).
Attribution: Co-Authored-By: Claude Opus 5.5 noreply@anthropic.com Claude-Session: https://claude.ai/code/session_01GFeMqxRbtUMiGVyDMxsvEq