General Correctness rules, Rust patterns, comments, avoiding over-engineering. When writing code always take these into account

Code Quality Guide Core Principle Production database. Correctness paramount. Crash corrupt. Correctness Rules 1. No workarounds or quick hacks. Handle all errors, check invariants 2. Assert often. Never silently fail or swallow edge cases 3. Crash on invalid state if it risks data integrity. Don't continue in undefined state 4. Consider edge cases. On long enough timeline, all possible bugs will happen Rust Patterns Make illegal states unrepresentable Exhaustive pattern matching Prefer enums over strings/sentinels Minimize heap allocations Write CPU friendly code (microsecond = long time) If Statements Wrong: Right: Use if statements only when both branches are expected paths. Comments Do: Document WHY, not what Document functions, structs, enums, variants Focus on why something is necessary Don't: Comments that repeat code References to AI conversations ("This test should trigger the bug") Temporal markers ("added", "existing code", "Phase 1") Avoid Over Engineering Only changes directly requested or clearly necessary Don't add features beyond what's asked Don't add docstrings/comments to unchanged code Don't add error handling for impossible scenarios Don't create abstractions for one time operations Three similar lines premature abstraction Index Mutations When code involves index inserts, deletes, or conflict resolution, double check the ordering against SQLite. Wrong ordering causes index inconsistencies. and easy to miss. Ensure understanding of IO model [Async IO model](../async io model/SKILL.md) Cleanup Delete unused code completely No backwards compat hacks (renamed vars , re exports, // removed comments)

code-quality