SimplicityHL toolchain

This action installs precompiled Simplex and Simfmt binaries. It does not install, select, or modify Rust or Cargo.

Usage

Set up the Rust version required by your project separately, then select the SimplicityHL components to install:

steps:
  - uses: actions/checkout@v6

  - name: Install Rust
    uses: dtolnay/rust-toolchain@stable
    with:
      toolchain: "1.91.0"

  - id: toolchain
    name: Install SimplicityHL tools
    uses: BlockstreamResearch/simplicityhl-toolchain@v1
    with:
      components: simplex@0.0.10,simfmt@0.0.2

  - run: simplex --version
  - run: simfmt --version

For security-sensitive workflows, pin actions to the full commit SHA of the release you reviewed instead of a movable tag.

Inputs

components

Required. A comma-separated list containing simplex, simfmt, or both. Add @VERSION to an entry to install a specific release:

components: simplex,simfmt
components: simplex@0.0.10
components: simplex@v0.0.10,simfmt@0.0.2

An entry without a version resolves the latest stable release. Empty entries, unknown components, duplicates, and malformed versions are rejected.

binstall-version

Optional. Version of cargo-binstall used to download and install the precompiled simfmt binary. Defaults to 1.22.0 and is ignored unless simfmt is selected.

Outputs

Output	Description
simplex-version	Installed Simplex version, or empty if it was not selected.
simfmt-version	Installed simfmt version, or empty if it was not selected.

- id: toolchain
  uses: BlockstreamResearch/simplicityhl-toolchain@v1
  with:
    components: simplex,simfmt

- run: printf '%s / %s\n' "$SIMPLEX_VERSION" "$SIMFMT_VERSION"
  env:
    SIMPLEX_VERSION: ${{ steps.toolchain.outputs.simplex-version }}
    SIMFMT_VERSION: ${{ steps.toolchain.outputs.simfmt-version }}

Precompiled binaries only

• Simplex is installed through simplexup.
• Simfmt is installed by the standalone precompiled cargo-binstall executable with only its official crate-metadata release strategy enabled.

Supported platforms are determined by each project's published release assets. The action does not maintain a separate architecture table. See the Simplex releases and Simfmt releases.

Development and releases

After checking out this repository, workflows can test the unpublished action with uses: ./. The action implementation is the root install script; the separate .github/scripts/simfmt-check helper is used only for repository format checks.