systematic-bugfinder

Start by reproducing the exact symptom, then trace one causal chain from entry point to the first wrong state. Test one hypothesis at a time with a discriminating check, fix the shared primitive rather than individual callers, and add a regression test that fails before and passes after the fix.

After confirming the root cause, search by mechanism rather than symptom: inspect every caller of the changed primitive, sibling branches, retry and cancellation paths, identity switches, and persisted state. Fix only confirmed neighboring defects and record dispositions for the rest.

Diagnose identifies and explains the cause without code changes. Fix diagnoses, implements, and verifies the reported bug. Audit classifies a supplied finding list as confirmed, stale, intentional, hypothetical, test gap, or duplicate, then fixes only confirmed defects.

Test cancellation or identity switches before and during awaits, completion after invalidation, a new run starting while the old one unwinds, and concurrent commits to the same destination. Use generation-scoped tokens and serialize writes to prevent overlapping commits.

Stop when the original symptom is reproduced and resolved, one causal chain explains the failure, all consumers of the changed primitive are inspected, two consecutive pattern searches find nothing new, and all regression and maintained-suite checks pass.