wizard

Follow the RED-GREEN cycle: write failing tests for behavior that does not exist yet, confirm they fail for the right reason, then implement the minimal code to pass. Add boundary tests (0, 1, -1, null, empty) and assert specific values so mutations like changing > to >= are caught.

Use atomic check-and-act operations instead of separate read-then-update steps, which create TOCTOU vulnerabilities. Lock the record, read state, act, then unlock, or use a single conditional UPDATE statement that only succeeds when the expected state still holds.

Create a GitHub issue for medium tasks (2-3 files) and complex tasks (4+ files or architectural impact). The issue holds acceptance criteria and serves as the source of truth throughout development, with progress comments and label updates at milestones.

Match the suite to change scope: related tests only for single-file fixes under 20 lines, feature test suites for multi-file changes, and all affected modules for cross-cutting, database, or auth changes. Never commit with failing tests.

Any change made inside a transaction is rolled back when an exception triggers rollback, including audit records and failure status updates. Persist error state outside the transaction in a catch block so it survives the rollback.