Setup Roc

A GitHub Action to download and setup the Roc compiler for Linux and macOS.

Usage

Add this step to your CI workflow:

For New Compiler Nightly Releases

- uses: roc-lang/setup-roc@cbe782d6f165b89c87d99f50a59ac4f5f73b4427
  with:
    version: nightly-new-compiler
    nightly-tag: nightly-2026-June-27-127861d # remove nightly-tag to just get the latest one

For Old Major Releases

- uses: roc-lang/setup-roc@cbe782d6f165b89c87d99f50a59ac4f5f73b4427
  with:
    version: alpha4-rolling

Note: we recommend using this @commit-sha way to specify the setup-roc version. This makes sure that the alpha4 release can not be altered if one of our github accounts is hacked.

For Old Nightly Releases

- uses: roc-lang/setup-roc@cbe782d6f165b89c87d99f50a59ac4f5f73b4427
  with:
    # Note: nightly hashes are not verified because they are updated regularly.
    version: nightly

Platform Support

This action supports the following platforms:

OS	Architecture	Status
Linux	x86_64	✅
Linux	arm64	✅
macOS	x86_64 (Intel)	✅
macOS	arm64 (Apple Silicon)	✅
Windows	x86_64	✅
Windows	arm64	❌

Windows arm64 can be made available again with the next zig release (after 0.16.0).

What it does

1. Detects your operating system and architecture
2. Downloads the appropriate Roc compiler release for your platform
3. Verifies the SHA256 checksum to ensure file integrity (skipped for nightly releases)
4. Extracts the compiler
5. Adds the Roc executable to the PATH

For new-compiler nightlies that include glue support, this action also exports:

Environment variable	Description
ROC_GLUE_DIR	Directory containing generated glue specs for the installed Roc version
ROC_RUST_GLUE	Rust glue spec path
ROC_ZIG_GLUE	Zig glue spec path
ROC_C_GLUE	C glue spec path
ROC_GLUE_PLATFORM_URL	URL of the matching glue platform package

Example:

- uses: roc-lang/setup-roc@<commit-sha-with-glue-support>
  with:
    version: nightly-new-compiler

- run: roc glue "$ROC_RUST_GLUE" ./platform/main.roc --output-dir ./platform

Pin to a setup-roc commit that includes glue support; older pinned commits do not export these variables.

Security

For major releases, the action verifies the SHA256 checksum of the downloaded file to ensure it hasn't been tampered with. If the checksum doesn't match, the action will fail.

For nightly releases, SHA256 verification is skipped because the files are updated regularly.