Cleanup codebase — local simplicity, ruthlessly applied

Code rots in two directions: outward (drift from the original design) and downward (accretion of dead state, redundant indirection, speculative ceremony). This skill addresses the second. The thesis is local: you are already in nearby code for some other reason; while you are there, remove what does not earn its keep.

Modern insight (2025): Kent Beck's Tidy First? thesis and Casey Muratori's dataflow-first design heuristic both converge on the same conclusion that this skill's compress-side operations operationalize — small, frequent, atomic cleanups embedded in the active commit stream beat scheduled "cleanup PRs" by a wide margin. Scheduled cleanups bundle unrelated concerns and become unreviewable; embedded cleanups stay reviewable because their scope is the file already in your hands.

See dead-fields for examples of dead struct fields, props, and class members. See redundant-wrappers for examples of single-line passthrough functions that should be inlined. See dead-config for stale feature flags, environment variables, and dead config branches.

Mandates, not suggestions

These are mandates, not suggestions. Internalize them as rules; do not paraphrase.

1. Minimize concepts, duplication, and ceremony.

Every concept the reader has to hold in their head has a cost. Every duplicated piece of logic has two places to drift apart. Every ceremonial wrapper, factory, or builder that does not protect a real boundary is a tax on every future reader. Reducing concepts is not the same as reducing lines — it is reducing the number of distinct things a reader has to track.