Built-in Hooks¶

prek includes fast, Rust-native implementations of popular hooks for speed and low overhead.

Use repo: builtin to select them directly, or keep a supported remote hook config and let prek use its automatic fast path.

	`repo: builtin`	Automatic fast path
Config remains usable by upstream `pre-commit`	No	Yes
Remote repository and manifest	Not used	Cloned at the pinned `rev`
Environment available for fallback	Not needed	Yes
Network needed for first preparation	No	Yes
How to opt out	Replace `repo: builtin` with a remote or local hook	Set the hook's declared language or `PREK_NO_FAST_PATH=1`

Check implementation notes when behavior matters

The Rust implementations target the same purpose as their upstream hooks, but a hook can have documented differences in arguments, defaults, or edge cases. Check its entry in the Hook Reference. To compare behavior, disable the fast path and run the pinned implementation.

Use built-in hooks directly¶

Add repo: builtin and select hooks by ID:

prek.toml.pre-commit-config.yaml

[[repos]]
repo = "builtin"
hooks = [
  { id = "trailing-whitespace" },
  { id = "check-added-large-files" },
]

repos:
  - repo: builtin
    hooks:
      - id: trailing-whitespace
      - id: check-added-large-files

List the builtins bundled with your installed prek version using:

prek util list-builtins

See the built-in hook reference for the complete list of hooks, supported arguments, and behavior notes.

Use the automatic fast path¶

For supported hooks from https://github.com/pre-commit/pre-commit-hooks, prek runs the built-in implementation automatically. Your existing remote config can stay compatible with upstream pre-commit. The rev field does not affect fast-path detection. It still selects the manifest that prek reads and the repository implementation used for fallback.

repos:
  - repo: https://github.com/pre-commit/pre-commit-hooks  # Enables fast path
    rev: v6.0.0  # Used for the manifest and fallback, not fast-path detection
    hooks:
      - id: trailing-whitespace

Note

In this mode, prek will still clone the repository and create the environment (e.g., a Python venv) to ensure full compatibility and fallback capabilities. However, the actual hook execution bypasses the environment and runs the native Rust code.

See fast-path support for the list of hooks that use the built-in implementation automatically. Other hooks run via the standard method.

Run the repository implementation¶

To use the pinned repository implementation for a single hook, explicitly set the language declared by that hook:

repos:
  - repo: https://github.com/pre-commit/pre-commit-hooks
    rev: v6.0.0
    hooks:
      - id: check-yaml
        language: python  # Use the pinned repository implementation

To disable the fast path for every hook in a prek invocation:

PREK_NO_FAST_PATH=1 prek run