Differences from pre-commit

General differences

• prek supports .pre-commit-config.yaml, .pre-commit-config.yml, and native prek.toml configuration files. Use prek util yaml-to-toml to convert an existing YAML config.
• prek implements some common hooks from pre-commit-hooks in Rust for better performance.
• prek supports repo: builtin for offline, zero-setup hooks.
• prek uses ~/.cache/prek as the default cache directory for repos, environments and toolchains.
• prek decouples hook environments from their repositories, allowing shared toolchains and environments across hooks.
• prek supports language_version as a semver specifier and automatically installs the required toolchains.
• prek supports files and exclude as glob lists (in addition to regex) via glob mappings. See Configuration Reference.
• prek supports a shell hook option for explicit shell-source execution through predefined adapters such as bash, sh, and pwsh. Upstream pre-commit runs entry directly; shell behavior must be spelled into entry itself.
• prek reports more precise configuration parsing errors, including exact source locations.

Behavioral divergences

These differences intentionally change upstream behavior instead of adding a compatible superset.

• File identification gives recognized extensions precedence over loose filename-prefix matches. For example, makefile.png is treated as a PNG image, while upstream identify also gives it makefile and text tags. Exact filename matches such as Cargo.toml still keep their name-specific tags.

Workspace mode

prek supports workspace mode, allowing you to run hooks for multiple projects in a single command. Each subproject can keep its own prek.toml or .pre-commit-config.yaml file.

See Workspace Mode for more information.

Language support

See the dedicated Language Support page for a complete list of supported languages, prek-specific behavior, and unsupported languages.

Recent releases added support for more managed hook runtimes, including Bun, Julia, Deno, and experimental .NET support.

Managed runtime download verification

For supported managed runtime downloads, prek verifies the downloaded archive or installer against the checksum published by the runtime's own distribution channel before extracting or installing it.

This helps catch corrupted or unexpectedly changed downloads before they are unpacked. It does not add an independent trust root: if an upstream release, mirror, or checksum file is compromised together with the archive, SHA-256 verification alone cannot detect that.

uv downloads are not covered by this behavior yet.

Command line interface

For a compatibility-focused command mapping, see Compatibility with pre-commit.

prek run

• prek run [HOOK|PROJECT]... supports selecting or skipping multiple projects or hooks in workspace mode, instead of only accepting a single optional hook id. See Running Specific Hooks or Projects for details.
• prek run can execute hooks in parallel by priority (hooks with the same priority may run concurrently), instead of strictly serial execution.
• In workspace mode, prek run can execute independent projects at the same directory depth concurrently, while still running child projects before their parents.
• prek provides dynamic completion for hook ids.
• prek run --dry-run shows which hooks would run without executing them.
• prek run --last-commit runs hooks on files changed by the last commit.
• prek run --directory <DIR> runs hooks on a specified directory.
• prek run --no-fail-fast lets you override the configured fail_fast setting for a single run and continue after failures.

prek install

• prek install and prek uninstall honor repo-local and worktree-local core.hooksPath when choosing where to manage Git shims.

prek validate-config

• prek validate-config accepts both prek.toml and .pre-commit-config.yaml.

prek list

prek list lists all available hooks, their ids, and descriptions. This provides a better overview of the configured hooks.

prek auto-update

• prek auto-update updates all projects in the workspace to their latest revisions.
• prek auto-update checks updates for the same repository only once, speeding up the process in workspace mode.
• prek auto-update supports --dry-run to preview the updates without applying them.
• prek auto-update supports --exit-code to exit non-zero when updates are available, and --check as an alias for --dry-run --exit-code.
• prek auto-update validates pinned SHA revisions against fetched upstream refs, including impostor-commit detection, and keeps stale # frozen: comments in sync when it can.
• prek auto-update supports the --cooldown-days option to skip releases newer than the specified number of days (based on the tag creation timestamp for annotated tags, or the tagged commit timestamp for lightweight tags).
• prek auto-update supports --exclude-repo to skip selected repositories while updating everything else.
• prek auto-update supports tag filtering with --include-tag, --exclude-tag, --repo-include-tag, and --repo-exclude-tag, using glob patterns to keep or remove matching tags before selecting an update.

prek sample-config

• prek sample-config can generate either YAML or TOML and can write directly to a file with --file.

prek util

• prek util identify shows the file-identification tags prek uses for filtering and debugging hook selection.
• prek util list-builtins lists all built-in hooks bundled with prek.
• prek util yaml-to-toml converts .pre-commit-config.yaml to prek.toml.

prek cache

• prek groups cache maintenance under prek cache instead of separate top-level clean and gc commands.
• prek cache gc removes unused cached repositories, environments and toolchains, and supports --dry-run.
• prek cache clean removes all cached data.
• prek cache dir and prek cache size help inspect the cache before or after cleanup.

Not implemented

The pre-commit hazmat subcommand introduced in pre-commit v4.5.0 is not implemented. This command is niche and unlikely to be widely used.