agent: builder model: opus max_turns: 80 budget_usd: 16 —
fs::Metadata::modified, links, file_id and time::since_epoch in std (#922 step 4, Part #125; unblocks K3b, O1)Score: self-hosting lane. #922 step 4 is what K3b (comptime_run.rs run_fingerprint, stamp_of: meta.modified() as nanoseconds since the epoch) and O1 (cache.rs used_at, first_link) wait for. The signatures are decided in #922 (owner, 2026-10-28) and Part III 17.1 already lists modified among Metadata’s readers (30-nikaia-tooling.md :1392); nothing here goes to the owner. First of the batch; K3b runs after it and uses modified.
Facts: Where things live, Traps already met, Commands
fs::Metadata::modified(self: ref fs::Metadata) -> time::Duration sync, touches = []: the last modification since the Unix epoch, following a link as fs::metadata does; time::Duration zero where the platform does not say or the time is before the epoch (Rust: .modified().ok().and_then(|t| t.duration_since(UNIX_EPOCH).ok()).unwrap_or_default(), the exact chain comptime_run.rs :840 and :918 use). d.in_nanos() then gives what K3b hashes.fs::Metadata::links(self: ref fs::Metadata) -> u64 sync, touches = []: the number of hard links (MetadataExt::nlink); 1 off Unix.fs::Metadata::file_id(self: ref fs::Metadata) -> (u64, u64)? sync, touches = []: device and inode (MetadataExt::dev, ino); null off Unix.time::since_epoch() -> time::Duration sync, no touches line (as time::now :4977: a clock read orders against everything): the wall clock, SystemTime::now().duration_since(UNIX_EPOCH), zero before the epoch. ADR-368 amendment, one paragraph: the monotonic clock (time::now, an Instant) measures spans within a run and never goes back; the wall clock is what a file’s time is stamped in, so only it can be compared with modified; it can go back, and a program that measures a span with it is wrong. Both exist because neither does the other’s job.Metadata gains three fields (modified: std::time::Duration, links: u64, file_id: Option<(u64, u64)>), filled in fs::metadata; its derives stay. ADR-319 amendment, one paragraph: these are readings of the name, no capability beyond the Root the metadata call already took.crates/nikaia-std/src/fs.rs: struct Metadata :420, impl Metadata :427-446, fn metadata :448-456 (add the readers after is_file, #[cfg(unix)] for MetadataExt, the off-Unix values as above).crates/nikaia-std/src/time.rs: fn now :25 (put since_epoch after it); in_nanos :121/:140 exists.crates/nikaia-std/std.contracts: fs::Metadata::is_file block :4530-4534 (model the three on it, a # comment line above each); time::now :4974-4981 (model since_epoch on it, no touches).docs/specification/30-nikaia-tooling.md: :1392 (the comment already says modified; make it len, is_dir, is_file, modified, links, file_id) and a sentence after the code block naming the three readers’ off-Unix answers; the std::time bullet :1571-1577 (one sentence: time::since_epoch() is the wall clock, comparable with modified, not monotonic, ADR-368).docs/specification/adr/adr-319.md, adr-368.md: the amendments above, each citing #922.fs.rs, time.rs, std.contracts, Part III, both ADR amendments. Test tests/compiler/tests/fs_metadata_times.nika (+ .stdout): the program writes a file under fs::scratch (or the root the other fs_* tests use: tests/compiler/tests/fs_writes_bytes_and_reads_them_back.nika), reads fs::metadata, and prints only booleans: modified is above zero, modified is not after time::since_epoch() plus one second, since_epoch is above 1.7e18 ns, links() == 1, file_id() != null (the suite runs on Linux), and a second metadata of the same file gives the same file_id. Commit std: fs::Metadata::modified, links, file_id and time::since_epoch, Part: #922 (step 3, fs::lock, stays open).The new test passes with nikaia test tests/compiler --both-settings on it; cargo test -p nikaia-std --lib fs:: time:: and the it filters fs metadata time pass; clippy (1.97 and 1.99.1, -p nikaia-std) clean; lower-std leaves every lowered/*.rs as committed. The report gives a Changelog line (it changes std), Rs2nika: none.
std.contracts refuses a (u64, u64)? result or a u64 reader (Found: with the message, Needs: architect decision), or a .stderr of an existing test changes.
crates/rs2nika/**, crates/nikaia-std/src/tools/lowered/project_members.rs (uncommitted in the tree, residue of the reverted GR, #1060), every docs/briefs/* but your report, and any file git status shows modified at your start. If 30-nikaia-tooling.md holds another agent’s hunk, commit only yours (builder-facts Traps already met, git apply --cached).
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/s922b-metadata-times.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