0.5.0

Release Notes

Released on 2026-08-27.

Highlights

Choose where hook toolchains come from

language_version now accepts a source preference alongside the version
request, letting you control where prek looks for a compatible toolchain when
it creates a hook environment. Use managed (the default) or system to choose
which source prek tries first while still allowing fallback and downloads. Use
only-managed or only-system to require one source.

For example, this local Ruff hook requires a Python 3.12 toolchain managed by
prek:

repos:
  - repo: local
    hooks:
      - id: ruff
        name: ruff
        language: python
        entry: ruff check
        additional_dependencies: [ruff]
        language_version:
          request: "3.12"
          preference: only-managed

With only-managed, prek reuses a compatible toolchain from its managed store
or downloads one when needed. It never falls back to Python from PATH, an OS
package manager, or a version manager, so toolchain selection does not depend on
the developer or CI machine's external environment.

Existing scalar values such as language_version: "3.12" continue to work. See
toolchain management and language_version
for the full source-selection behavior. (#2613)

Breaking changes

The breaking changes in this release are mostly small cleanups, and most users should not be affected.

• Group names can no longer start with @. This prefix is now reserved for special group selectors such as the new @ungrouped selector. (#2617)
• PREK_MAX_CONCURRENCY has been removed. Use PREK_CONCURRENT_HOOKS and PREK_CONCURRENT_BATCHES to control hook and per-hook batch concurrency separately. (#2620)
• The top-level prek init-template-dir command has been removed. Use prek util init-template-dir, or prek init-templatedir for drop-in compatibility with pre-commit. (#2623)
• prek auto-update has been removed. Use prek update, or prek autoupdate for drop-in compatibility with pre-commit. (#2619)

Enhancements

• Add configurable toolchain source preferences (#2613)
• Allow explicit language: python to opt out of fast-path hooks (#2608)
• Group run and update options in CLI help (#2629)
• Preserve terminal theme contrast for status labels (#2592)
• Add @ungrouped group selector (#2617)
• Retry uv installation with static musl binary (#2600)
• Support {hook_repo} placeholder in hook entry (#2602)

Bug fixes

• Expose the git work tree to hooks running outside the git root (#2579)
• Isolate local hook environment installation (#2615)
• Preserve hook config deserialization error locations (#2573)
• Resolve hook log files from their config directory (#2580)
• Track explicit config paths as absolute paths (#2574)

Documentation

• Document prek run architecture (#2630)
• Publish versioned documentation (#2626)

Contributors

• @jeromeheissler
• @gurgeous
• @j178

Install prek 0.5.0

Install prebuilt binaries via shell script

curl --proto '=https' --tlsv1.2 -LsSf https://github.com/j178/prek/releases/download/v0.5.0/prek-installer.sh | sh

Install prebuilt binaries via powershell script

powershell -ExecutionPolicy Bypass -c "irm https://github.com/j178/prek/releases/download/v0.5.0/prek-installer.ps1 | iex"

Install prebuilt binaries via Homebrew

brew install prek

Download prek 0.5.0

File	Platform	Checksum
prek-aarch64-apple-darwin.tar.gz	Apple Silicon macOS	checksum
prek-x86_64-apple-darwin.tar.gz	Intel macOS	checksum
prek-aarch64-pc-windows-msvc.zip	ARM64 Windows	checksum
prek-i686-pc-windows-msvc.zip	x86 Windows	checksum
prek-x86_64-pc-windows-msvc.zip	x64 Windows	checksum
prek-aarch64-unknown-linux-gnu.tar.gz	ARM64 Linux	checksum
prek-i686-unknown-linux-gnu.tar.gz	x86 Linux	checksum
prek-riscv64gc-unknown-linux-gnu.tar.gz	RISCV Linux	checksum
prek-s390x-unknown-linux-gnu.tar.gz	S390x Linux	checksum
prek-x86_64-unknown-linux-gnu.tar.gz	x64 Linux	checksum
prek-armv7-unknown-linux-gnueabihf.tar.gz	ARMv7 Linux	checksum
prek-aarch64-unknown-linux-musl.tar.gz	ARM64 MUSL Linux	checksum
prek-i686-unknown-linux-musl.tar.gz	x86 MUSL Linux	checksum
prek-x86_64-unknown-linux-musl.tar.gz	x64 MUSL Linux	checksum
prek-arm-unknown-linux-musleabihf.tar.gz	ARMv6 MUSL Linux (Hardfloat)	checksum
prek-armv7-unknown-linux-musleabihf.tar.gz	ARMv7 MUSL Linux	checksum

Verifying GitHub Artifact Attestations

The artifacts in this release have attestations generated with GitHub Artifact Attestations. These can be verified by using the GitHub CLI:

gh attestation verify <file-path of downloaded artifact> --repo j178/prek

You can also download the attestation from GitHub and verify against that directly:

gh attestation verify <file-path of downloaded artifact> --bundle <file-path of downloaded attestation>