Use cx in GitHub Actions

Use the setup-cx action when a workflow needs a small conda bootstrapper without installing Miniconda, Miniforge, or a larger distribution first.

The default action path downloads the cx release asset, verifies the published SHA256 checksum, adds cx to PATH, and runs cx info. That first conda command automatically bootstraps the managed prefix.

Add cx to a workflow

Pin the action to a conda-express release tag:

jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - uses: jezdez/conda-express/.github/actions/setup-cx@26.5.2.post6
      - run: cx info

When the action ref is a conda-express release tag and version is omitted, the action installs that same cx release. This keeps the action code and the downloaded binary aligned.

After automatic bootstrap, use cx the same way you would use conda:

jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - uses: jezdez/conda-express/.github/actions/setup-cx@26.5.2.post6
      - run: cx create -n test python=3.12 pytest
      - run: cx run -n test pytest

Install without eager bootstrap

Set bootstrap: false when a job only needs to inspect the binary or wants to defer automatic bootstrap:

jobs:
  inspect:
    runs-on: ubuntu-latest
    steps:
      - id: setup-cx
        uses: jezdez/conda-express/.github/actions/setup-cx@26.5.2.post6
        with:
          bootstrap: false
      - run: test -x "${{ steps.setup-cx.outputs.cx-path }}"

Any later cx command bootstraps the prefix before conda handles its arguments. Set CX_PREFIX, CX_BUNDLE, or CX_OFFLINE on that command when the job needs non-default bootstrap controls.

Install a different cx version

Pass version when the action ref and binary version should differ:

steps:
  - uses: jezdez/conda-express/.github/actions/setup-cx@26.5.2.post6
    with:
      version: 26.5.2.post6

This is mainly useful for testing the action from a branch or local checkout. For normal workflows, prefer pinning the action to the release tag you want to run.

Verify artifact attestations

Checksum verification is enabled by default. For stricter provenance checks, enable GitHub Artifact Attestation verification and grant the job the additional read permission:

jobs:
  test:
    runs-on: ubuntu-latest
    permissions:
      contents: read
      attestations: read
    steps:
      - uses: jezdez/conda-express/.github/actions/setup-cx@26.5.2.post6
        with:
          verify-attestation: true
          github-token: ${{ github.token }}
      - run: cx info

verify-attestation: true fails closed when github-token is missing. The token is passed to gh attestation verify; it is not needed for the default checksum-only path.

Use a custom install directory

By default the action installs cx into the runner temp directory. Use install-dir if later workflow steps expect a stable location:

steps:
  - uses: jezdez/conda-express/.github/actions/setup-cx@26.5.2.post6
    with:
      install-dir: ${{ runner.temp }}/tools

The install directory is added to PATH unless add-to-path: false is set.

See Installer reference for the complete action input and output reference.