Developing with Cargo

Every NativeLink crate compiles cleanly with plain Cargo. Use this workflow if you want a smaller dev shell, faster incremental builds during iteration, or just don't have Bazel installed.

Prerequisites

• A recent stable Rust toolchain. The exact version is pinned in rust-toolchain.toml; rustup will pick it up automatically.
• protoc 3+ on $PATH (for the gRPC proto generation step).
• On Linux: mold is automatic if installed.

First build

git clone https://github.com/TraceMachina/nativelink
cd nativelink
cargo build --workspace

First build is a few minutes (dependency compilation); subsequent incremental builds are typically a few seconds.

Common commands

# Build everything.
cargo build --workspace

# Run all tests.
cargo test --workspace

# Run a specific crate's tests.
cargo test -p nativelink-store

# Run the server.
cargo run -p nativelink -- /path/to/config.json5

# Format.
cargo fmt --all

# Lint (CI runs this too).
cargo clippy --all-targets -- -D warnings

Faster incremental builds

A few flags that help:

• mold as linker (Linux):

  # ~/.cargo/config.toml
  [target.x86_64-unknown-linux-gnu]
  linker = "clang"
  rustflags = ["-C", "link-arg=-fuse-ld=mold"]

• CARGO_TARGET_DIR set to a shared directory across checkouts to reuse incremental artifacts.

• Pointing Cargo at a sccache backed by NativeLink:

  export RUSTC_WRAPPER=sccache
  export SCCACHE_BUCKET_URL=grpc://localhost:50051

Caveats

• Some Bazel-only crates (the LRE flake outputs, the Bazel-generated proto bindings) don't have Cargo equivalents. If you're touching those, you'll need Bazel.
• The CI image runs Bazel — your Cargo build passing doesn't guarantee CI passes. Run bazel test //... (or nix develop- based equivalent) before submitting.

For the Bazel-based workflow, see Develop with Bazel.