Benchmark scripts, shared fixtures, and local result artifacts live here. These benchmarks are local diagnostics for Hunk's core promise: fast loading, fast first render, fast navigation, and predictable memory use on large diffs.

Run the default local benchmark suite with one JSON result file:

bun run bench -- --samples 3 --out benchmarks/results/local.json

Run optional competitor comparisons when the tools are installed:

bun run bench -- --samples 3 --include-competitors --out benchmarks/results/local-with-competitors.json

Run focused scripts while iterating:

bun run bench:bootstrap-load
bun run bench:working-tree-load
bun run bench:changeset-parse
bun run bench:render-layout
bun run bench:highlight-prefetch
bun run bench:large-stream
bun run bench:large-stream-profile
bun run bench:memory
bun run bench:competitors

• bootstrap-load.ts — measures bootstrap and git-loader cost on a synthetic large repo, including file-pair bootstrap.
• working-tree-load.ts — measures git working-tree loads across small, medium, large, many-untracked, and few-large-untracked repos.
• changeset-parse.ts — measures patch normalization, Pierre parsing, patch chunking, and normalized DiffFile construction for many-small-files, balanced, and large-single-file patches.
• render-layout.ts — measures pure split/stack row building, section geometry, and review-plan construction for many-small-files, balanced, and large-single-file streams.
• highlight-prefetch.ts — measures selected-file highlight startup and adjacent prefetch readiness.
• large-stream.ts — measures large split-stream first-frame and scroll cost.
• large-stream-profile.ts — optional local profiler for the main pure planning stages behind the large split-stream benchmark.
• memory.ts — optional local RSS/heap profiler after fixture loading, planning, first frame, and next-hunk navigation.
• competitors.ts — optional local informational comparisons against git diff --no-ext-diff, delta, difftastic, and diff-so-fancy when installed.
• large-stream-fixture.ts and lib/fixtures.ts — shared deterministic synthetic fixtures.

Each script prints METRIC name=value lines. benchmarks/run.ts repeats scripts, aggregates samples, prints a readable summary, and can write JSON:

{
  "version": 1,
  "samplesPerBenchmark": 3,
  "results": [
    {
      "name": "large-stream/cold_first_frame_ms",
      "unit": "ms",
      "samples": [61.2, 60.8, 62.1],
      "median": 61.2,
      "p75": 62.1,
      "p95": 62.1,
      "threshold": {
        "maxRegressionRatio": 1.15,
        "minAbsoluteRegression": 5
      },
      "comparable": true
    }
  ]
}

• These benchmarks are intentionally local-only for now. They are useful diagnostics, but CI proved too noisy and slow for PR gating.
• The default local suite excludes optional memory profiling, pure-planning profiling, and competitor comparisons. Run those focused scripts when deeper diagnostics are needed.
• Competitor comparisons are informational because installed tool versions and feature parity vary by environment.
• Use --samples 5 locally when validating borderline changes.
• Use benchmarks/results/ for local benchmark output; result files in that directory are ignored by default.