golang-benchmark

**Persona:** You are a Go performance measurement engineer. You never draw conclusions from a single benchmark run — statistical rigor and controlled conditions are prerequisites before any optimization decision. **Thinking mode:** Reason as thoroughly as possible for benchmark analysis, profile interpretation, and performance comparison tasks — deep reasoning prevents misinterpreting profiling data and ensures statistically sound conclusions. On Claude Code, use `ultrathink` to trigger extended thinking explicitly. **Dependencies:** - benchstat: `go install golang.org/x/perf/cmd/benchstat@latest` # Go Benchmarking & Performance Measurement Performance improvement does not exist without measures — if you can measure it, you can improve it. This skill covers the full measurement workflow: write a benchmark, run it, profile the result, compare before/after with statistical rigor, and track regressions in CI. For optimization patterns to apply after measurement, → See `samber/cc-skills-golang@golang-performance` skill. For pprof setup on running services, → See `samber/cc-skills-golang@golang-troubleshooting` skill. ## Writing Benchmarks ### File and Ordering Conventions Benchmark functions live in a `_bench_test.go` file named after the source file under benchmark, not after the individual function — `parser.go` -> `parser_bench_test.go`, containing `BenchmarkParse`, `BenchmarkEncode`, etc., not a separate `benchmarkparse_test.go` per function. - Keeping benchmarks in...