agent: builder model: opus max_turns: 80 budget_usd: 16 —
Score: compiler bug, false acceptance (nikaia check passes, rustc Lifetime may not live long enough); found by this lane’s b11 (#1048 row d), cause traced by b11, two places to change.
Facts: Where things live, Traps already met, Commands
fn longer(a: ref String, b: ref String) -> ref String {
if a.len() >= b.len() { return a }
return b
}
struct Holder { f: fn(ref String, ref String) -> ref String }
fn main() {
let h = Holder { f: longer }
println(f"{h.f("abcd", "abcd").len()}")
}Rows:
String without ref is refused NK1106 at the field today, not yours). Must print 4.1.... -> ref String sync.tests/compiler/tests/a_function_type_with_two_views.nika (b11’s rows a-c and the sync list row).Syntax: a field holding code is called h.f(a, b) ((h.f)(..) does not parse); struct fields are separated by commas. An unfixed binary for before/after probes: /home/user/nikaia-suite/target/fast/nikaia.
Two places repeat the #703 rule a function type handed two views or more that gives back one hands back the call’s own view, and both say sync only. Change both, in one commit:
crates/nikaia-std/src/tools/views.nika:425 views_the_call_s: drop if !code.is_sync { return false }, so holds_view stops giving the struct an 'a for such a field. Its callers: holds_view (views.nika:411) and borrowing in emit_tables.nika (nikaia run scripts/where.nika -- views_the_call_s); check each still means what it says for pausing code.crates/nikaia-std/src/tools/emit_core_types.nika, the kept branch (if !runs, the !code.is_sync && lent block, about :213-221): today Kept<dyn for<'call> Fn(&'call str, &'call str) -> BoxedIn<'call, &'a str>>; when the result is one of the lent views (views_the_call_s holds, or the same count the runs branch uses since b11), write the outcome with EmitLifetimes::Call: BoxedIn<'call, &'call str>. Lists through a_list_read_as_a_slice, as b11 did.
Changing only the emitter gives Lifetime parameter 'a is never used for row b (b11 tried it).Tests:.tests/compiler/tests/a_pausing_two_view_field.nika + .stdout (rows a and b, also row a over ref Vec[i64] if it fails the same way today; say which under Tests:). Commit emit: a struct field holding pausing code with two views in and a view out names the call's lifetime (Fixes #1061).The new test fails on the unfixed compiler and passes through nikaia test --project tests/compiler --both-settings (by name); the tests/compiler tests whose names contain function_type, two_view, code_param, kept, struct_field or lambda pass (run by name); lower-std fixpoint clean (lowered/views.rs, lowered/emit_core_types.rs, and lowered/emit_tables.rs if touched); build, fmt, clippy, pre-push-check.sh; committed locally. Changelog: one line. Stop about 15 turns before max_turns, commit what is finished and report partial.
An edit is needed outside views.nika, emit_core_types.nika, emit_tables.nika, their lowered twins and the test; a tools/*.nika of the toolchain changes its lowering through the views_the_call_s change in a way rustc refuses (report the file and line); an error in another agent’s file.
Not yours, never stage: every file git status shows modified or untracked at your start, and every docs/briefs/* file except your report.
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/bugs/b12-1061-pausing-two-view-field.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