expr-printf-rust-rewrite

Task gallery / Software engineering / Version 1

Reference solution (oracle): Pass
No-op resistance check: Pass
QA verdict: Not recorded
Aggregate eligibility: Eligible version

The task

Rewrite GNU expr + printf in Rust (byte-exact, LCALL=C) Reimplement GNU coreutils expr and printf as a single in-process Rust library. For every test case your output must be byte-for-byte identical to what the reference expr / printf prints for the same command-line arguments, under LCALL=C. The crate lives at /app (package + library name gnucoreutil). Edit /app/src/lib.rs (and any modules you add under /app/src/).…

Excerpt only; not a complete executable task specification. Task ID task_db45dba828f34ded · version 1. Selection status: not fully recorded.

Results by model and effort

This exact task version only. Every rate is passes / valid runs with a Wilson 95% interval; n≤2 remains counts only. Macro aggregation does not apply within a single task. Baselines are summarized in the quality gates, not ranked. A passed no-op resistance check means that doing nothing did not solve the task.

Current evidence

Model / effort	Verifier result [95% Wilson]	Diagnostic labels / valid	HARNESS_ERROR · excluded	Outcome classes
Claude Opus 5 · default (unverified)	0/5 · 0.0% [0.0%, 43.4%]	5 / 5	0	GOOD_FAILURE: 5 BAD_FAILURE: 0 GOOD_SUCCESS: 0 BAD_SUCCESS: 0

Legacy evidence

Model / effort	Verifier result [95% Wilson]	Diagnostic labels / valid	HARNESS_ERROR · excluded	Outcome classes

Difficulty, with uncertainty

Selected-best difficulty: 100.0% [56.6%, 100.0%]. This is one minus the best measured current-row pass rate among rows with at least five valid runs.

The maximum is selected from the observed rows, so the estimate is optimistic. Its Wilson interval is not adjusted for model selection. “Hard” requires qualifying GOOD_FAILURE evidence; the threshold flag additionally requires the interval and recorded quality gates to meet the documented rule. This is not independent validation. Threshold flag: yes.

Every recorded run

9 recorded trials, including controls. Diagnostic labels do not replace verifier reward. Labels and quality checks are source declarations, not independently attested here. Internal evidence remains private; a missing public URL is shown explicitly. Records with invalid or absent rewards are not scored.

Run / model	Date / source	Reward / eligibility	Diagnostic class / source	Resources	Evidence
`trial_c9e7fd7b2f1a4df7` oracle@@	Oct 10, 2026 console	No reward · excludedno_reward	No diagnostic label No diagnostic source	Tokens: — Turns: — Cost: —	Not publicly available
`trial_df9cfe3b7b654af1` nop@@	Oct 10, 2026 console	No reward · excludedno_reward	No diagnostic label No diagnostic source	Tokens: — Turns: — Cost: —	Not publicly available
`trial_72369934665340a6` nop@@	Oct 11, 2026 console	0 · valid	No diagnostic label derived	Tokens: — Turns: — Cost: —	Not publicly available
`trial_a32b8d682f854bca` oracle@@	Oct 11, 2026 console	1 · valid	No diagnostic label derived	Tokens: — Turns: — Cost: —	Not publicly available
`trial_02adf4868812493c` Claude Opus 5 · default (unverified)	Oct 11, 2026 console	0 · valid	GOOD_FAILURE frozen-classifier	Tokens: 290,201 Turns: 182 Cost: $34.4516	Not publicly available
`trial_1722f760b46b46e2` Claude Opus 5 · default (unverified)	Oct 11, 2026 console	0 · valid	GOOD_FAILURE frozen-classifier	Tokens: 275,947 Turns: 120 Cost: $23.7852	Not publicly available
`trial_277dcbc9ab9b498f` Claude Opus 5 · default (unverified)	Oct 11, 2026 console	0 · valid	GOOD_FAILURE frozen-classifier	Tokens: 278,183 Turns: 127 Cost: $26.2183	Not publicly available
`trial_b8c4093787d34d29` Claude Opus 5 · default (unverified)	Oct 11, 2026 console	0 · valid	GOOD_FAILURE frozen-classifier	Tokens: 302,734 Turns: 129 Cost: $28.0859	Not publicly available
`trial_e8715a582dd64400` Claude Opus 5 · default (unverified)	Oct 11, 2026 console	0 · valid	GOOD_FAILURE frozen-classifier	Tokens: 256,151 Turns: 149 Cost: $26.9822	Not publicly available