Setup Rust

GitHub Action to set up a Rust toolchain with sensible CI defaults and caching.

Features

• Installs rustup and the requested toolchain (or reads rust-toolchain.toml)
• Caches the Cargo registry and build artifacts via Swatinem/rust-cache
• Sets CI-optimized environment variables (no incremental builds, sparse registry, etc.)
• Installs extra cargo binaries via pre-compiled binaries (install-action)
• Includes clippy and rustfmt by default

Usage

- uses: crustacean-dev/setup-rust@v1

With options

- uses: crustacean-dev/setup-rust@v1
  with:
    toolchain: nightly
    components: clippy,rustfmt,miri
    targets: wasm32-unknown-unknown
    cargo-bins: cargo-nextest cargo-llvm-cov
    rustflags: "-D warnings -A dead_code"

Using rust-toolchain.toml

When the toolchain input is left empty and a rust-toolchain or rust-toolchain.toml file is present, the action lets rustup read it automatically. Additional components and targets are still installed on top.

- uses: crustacean-dev/setup-rust@v1
  with:
    components: "" # already defined in rust-toolchain.toml

Accessing outputs

- uses: crustacean-dev/setup-rust@v1
  id: rust
- run: echo "Using ${{ steps.rust.outputs.rustc-version }}"

Inputs

Input	Default	Description
toolchain	""	Rust toolchain to install (e.g. stable, nightly, 1.80.0). Reads rust-toolchain.toml if empty.
components	clippy,rustfmt	Comma-separated list of rustup components to install
targets	""	Comma-separated list of additional targets to install
cache	true	Enable Cargo caching via Swatinem/rust-cache
cache-key	""	Additional cache key for differentiation
cache-shared-key	""	Shared cache key stable across jobs
cargo-bins	""	Space-separated list of cargo binaries to install (e.g. cargo-nextest cargo-llvm-cov)
rustflags	-D warnings	Value for RUSTFLAGS. Empty string to not override.

Outputs

Output	Description
rustc-version	Installed rustc version string
cargo-version	Installed cargo version string
cachekey	Short hash (12 chars) suitable for cache keying

CI Environment Variables

The action sets the following environment variables unless they are already defined:

Variable	Value	Reason
CARGO_INCREMENTAL	0	Incremental compilation is useless in CI and wastes disk
CARGO_PROFILE_DEV_DEBUG	0	Reduces debug info for faster compilation
CARGO_TERM_COLOR	always	Forces color output in logs
RUST_BACKTRACE	short	Short backtraces on panic
CARGO_REGISTRIES_CRATES_IO_PROTOCOL	sparse	Faster registry index updates
RUSTFLAGS	-D warnings	Denies warnings by default (configurable)

License

MIT