setup-march

A GitHub Action that installs the March programming language in your CI workflow.

Usage

- uses: march-language/setup-march@v1
  with:
    march-version: main

Inputs

Input	Description	Default
march-version	Branch, tag, or commit SHA to install	main
ocaml-compiler	OCaml compiler version used to build March	5.3.0
github-token	GitHub token to avoid API rate limits	${{ github.token }}

Outputs

Output	Description
march-version	The commit SHA of the installed March version
march-path	Path to the March installation directory

Example

name: CI
on: [push, pull_request]

jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - uses: march-language/setup-march@v1
        with:
          march-version: main

      - run: march my_program.march

How it works

1. Resolves the march-version input to a commit SHA for reliable cache keying.
2. Restores the March build from cache if available (keyed by SHA + OS + OCaml version).
3. Always installs system dependencies (blake3, brotli, zstd, llvm).
4. On a cache miss: sets up OCaml via ocaml/setup-ocaml, clones the march repo, installs opam dependencies, and builds with dune.
5. Adds march to PATH.

Cached runs skip OCaml setup and the March build — the expensive parts — keeping them fast.

Step 3 is deliberately not cache-gated. The march binary dynamically links against these libraries, and they install to system paths outside the cached directory (~/.local/march). Skipping them on a cache hit yields a restored binary that cannot load, failing with exit 127 on every invocation.

Platform support

OS	Status
Ubuntu	Supported
macOS	Supported
Windows	Not supported