prek

prek: pre-commit hooks

prek (github.com/j178/prek) reads the same .pre-commit-config.yaml as Python pre-commit — existing configs work unchanged. Migration is: install prek, run prek install.

Install

Via	How
mise (preferred)	prek = "latest" under [tools] (registry: aqua:j178/prek)
Homebrew	brew install prek
cargo	cargo install prek

Repo-local hooks (the common case)

Repo-local toolchain commands use repo: local + language: system:

# .pre-commit-config.yaml
repos:
  - repo: local
    hooks:
      - id: fmt
        name: cargo fmt (check)
        entry: cargo fmt --all --check
        language: system
        types: [rust]
        pass_filenames: false
      - id: clippy
        name: cargo clippy (-D warnings)
        entry: cargo clippy --workspace --all-targets -- -D warnings
        language: system
        types: [rust]
        pass_filenames: false
      - id: workspace-lints
        name: cargo workspace-lints
        entry: cargo workspace-lints
        language: system
        files: (^|/)Cargo\.toml$
        pass_filenames: false

Remote-repo hooks work as in pre-commit; pin rev: to a tag.

Activate and run

prek install            # write the git hook (once per clone)
prek run --all-files    # run every hook against the whole tree (CI / first run)

Offer a repo task so clones activate consistently, e.g. mise: [tasks.hooks] run = "prek install".

Rules

• pass_filenames: false for whole-workspace commands (cargo, tsc, …) — otherwise the hook receives the staged file list as arguments.
• Scope manifest-only hooks with files: (regex) instead of types:.
• language: system runs commands from the committer's PATH — toolchain managers (mise, rustup) must be active in the git environment.
• Hooks see staged files only; use prek run --all-files in CI to gate the full tree.