GitHub Action to install Crystal programming language and Shards package manager.

Works on Ubuntu, macOS, Windows.

Configurator: get a pre-made config for your exact use case!

steps:
  - uses: crystal-lang/install-crystal@v1
  - run: crystal eval "puts 1337"

steps:
  - uses: actions/checkout@v4
  - uses: crystal-lang/install-crystal@v1
    with:
      crystal: 1.11
  - run: shards install
  - run: crystal spec

    strategy:
      fail-fast: false
      matrix:
        include:
          - {os: ubuntu-latest, crystal: latest}
          - {os: ubuntu-latest, crystal: nightly}
          - {os: macos-latest}
          - {os: windows-latest}
    runs-on: ${{matrix.os}}
    steps:
      - uses: crystal-lang/install-crystal@v1
        with:
          crystal: ${{matrix.crystal}}
      - uses: actions/checkout@v4
      - run: shards install
      - run: crystal spec
      - run: crystal tool format && git diff --exit-code
        if: matrix.crystal == 'latest'

Find usages in the wild!

Alternatively, you can use the container-based approach as in the starter workflow (without this action), but the advantage here is the unified approach to installation across 3 systems. Using a custom container has disadvantages on its own, too.

• • crystal: 1.1.0, crystal: 1.2

    Install a particular release of Crystal (if the full version is specified), or the latest patch version of a release series.

  • crystal: latest (default)

    Install the latest released version of Crystal.

  • crystal: nightly

    Install Crystal from the latest continuous build on crystal.git master.

  • crystal: "branch:foo/bar"

    Install Crystal from the latest maintenance build on crystal.git branch specified after branch:.

• • shards: true (default)

    Ensure that some released version of Shards is available. This uses the build that's bundled with Crystal's releases. Other options are slower, as building Shards is a necessary step then.

  • shards: false

    Ensure that shards executable is not available.

  • shards: latest

    Build and install the latest released version of Shards.

  • shards: 0.14.0, shards: 0.16

    Build and install a particular release of Shards (if the full version is specified), or the latest patch version of a release series.

  • shards: nightly

    Build and install the latest commit of shards.git master.

• arch: x86_64, arch: x86 (defaults to current OS arch)

  The architecture of the build of Crystal to download.

• destination: some/path

  The directory to store Crystal in, after extracting. Will directly affect outputs.path (the default is in a temporary location).

• annotate: true (default)

  Display compilation and spec errors as GitHub code annotations.

• token: ${{ github.token }}

  Personal access token (auto-populated).

• crystal (${{ steps.some_step_id.outputs.crystal }})

  The actual version of Crystal (as a ref in crystal-lang/crystal.git) that was installed.

• shards (${{ steps.some_step_id.outputs.shards }})

  The actual version of Shards (as a ref in crystal-lang/shards.git) that was installed.

• path (${{ steps.some_step_id.outputs.path }})

  The path where Crystal was extracted to, so you can use '[path]/bin/crystal', '[path]/src' etc.