/perf

description: "The performance discipline: measure before touching, benchmark what matters, prove regressions and fixes with numbers."

The user invoked /procoder:perf with arguments: $ARGUMENTS

The launcher is: "${CLAUDE_PLUGIN_ROOT}/hooks/launcher.sh"

Performance work without numbers is storytelling. The discipline:

1. **Baseline first.** Run `launcher.sh bench` — it runs the Go benchmarks and compares against `.procoder/bench/baseline.txt`. No baseline yet? `launcher.sh bench --save` records one BEFORE you touch anything. No benchmarks yet? Write one for the hot path the change touches — that is the first task, not an afterthought. 2. **Change, then measure again.** `launcher.sh bench` marks any regression beyond `[bench] threshold` (default 10%) and exits 1. Improvements are numbers too — quote the delta, not adjectives. 3. **Save deliberately.** A new baseline (`--save`) is a decision that the current numbers are the new normal — take it after a reviewed improvement, never to silence a regression. 4. Results are single-run and machine-local; treat small deltas as noise and cross-platform comparisons with the warning the tool prints. For deeper hunts, profile (pprof) before optimizing.