Git Bench

Benchmarks git client implementations against a clone of vercel/next.js:

Runner	Implementation description
git-cli	Subprocess to system git
libgit2-ffi	bun:ffi bindings to system libgit2
gitoxide	gix CLI (Rust)
isomorphic-git	Pure JS over node:fs
ziggit	Pure Zig implementation

Operations measured:

1. Current branch: Resolve HEAD to a short branch name.
2. Status: Worktree and index status (porcelain).
3. Log (100): Walk the 100 most recent commits from HEAD.
4. Tracked files: Enumerate all paths tracked in the index.
5. Changed files: Name-only diff between HEAD~1 and HEAD.
6. Read 25 blobs: Read 25 fixed file blobs at HEAD by path.

Prerequisites

• Docker installed and running on your system.
• Bun installed locally (for running the web dashboard).

No local installation of git, gix (gitoxide), or libgit2 is required; all benchmark runners are executed inside a Docker container.

Running

bun install
bun run bench         # Build Docker image, clone repo, run benchmarks (all inside Docker)
bun run dev           # Start the dashboard at http://localhost:3000

Configuration

You can configure the benchmark using packages/bench/bench.config.json:

{
  "git": {
    "remote": "https://github.com/vercel/next.js.git",
    "repo": ".git-bench-repos/next.js"
  },
  "bench": {
    "samples": 5,
    "results": "results.json"
  },
  "bin": {
    "gix": "gix",
    "libgit2": null,
    "ziggit": "ziggit"
  }
}

Key	Description
git.remote	Clone URL for the repository to benchmark
git.repo	Local path (relative to project root) for the cloned repo
bench.samples	Number of timed iterations per operation
bench.results	Output path for results JSON (relative to packages/bench/)
bin.gix	Path to the gix (gitoxide) binary
bin.libgit2	Path to the libgit2 shared library, or null to skip
bin.ziggit	Path to the ziggit binary

Methodology

Each runner runs one warmup iteration, followed by SAMPLES timed iterations of each operation. Setup tasks (like opening the repository or loading JS modules) run outside the timed region to avoid skewing the results. The dashboard displays the median time per operation; the underlying JSON also records the mean, min, max, and sample count.

The libgit2-ffi runner uses minimal bun:ffi bindings in packages/bench/src/runners/libgit2-ffi.ts.