debuglisted

A bug is a falsified assumption. Find the assumption, falsify it deliberately, observe the divergence, narrow until one line owns the lie. No speculation, no shotgun edits, no "fix and rerun" guessing. ## When to Apply / NOT Apply: test fails and cause unclear; production stack trace; intermittent / flaky behavior; wrong output without crash; regression after known commit window; heisenbug. NOT apply: performance regression with correct outputs; security defect; symptom obvious from one-line read; architectural confusion. ## Anti-patterns - **Shotgun debugging**: editing several files hoping one fixes it. - **Print-and-rerun**: adding logs without a target observation. - **Premature fix**: patching symptom before isolating root cause. - **Ignoring the trace**: stack frames are evidence. - **Changing two variables at once**: defeats falsification. - **Deleting the failing test**: capturing the bug is the asset. ## Hypothesis Loop (language-neutral) 1. **Observe** — Reproduce the failure deterministically. 2. **Trace** — Read the failure artifact (stack, log, core dump). 3. **Hypothesize** — One falsifiable claim. Rank hypotheses by likelihood. 4. **Instrument** — Insert minimum probe (breakpoint, structured log, assertion). 5. **Run** — Execute the minimal repro. 6. **Confirm or refute** — If refuted, demote and pick next hypothesis. 7. **Narrow** — Binary-search the suspect range. Use `git bisect` for regressions. 8. **Confirm root cause** — Inverse test: removing/alte