Rust Packages

Rust packages live in pkgs/<name>/default.nix using rustPlatform.buildRustPackage.

Minimal Example

{
  lib,
  rustPlatform,
  fetchFromGitHub,
}:

rustPlatform.buildRustPackage (finalAttrs: {
  pname = "example";
  version = "1.0.0";

  src = fetchFromGitHub {
    owner = "example";
    repo = "example";
    tag = "v${finalAttrs.version}";
    hash = "sha256-...";
  };

  cargoHash = "sha256-...";

  meta = {
    description = "Example Rust tool";
    license = lib.licenses.mit;
    mainProgram = "example";
  };
})

Essential Attributes

• cargoHash — SRI hash of vendored Cargo dependencies. Set to lib.fakeHash to get the correct value from the build error.
• cargoBuildFlags — extra flags passed to cargo build (e.g., [ "--package" "foo" "--bin" "foo" ] for workspaces)
• cargoTestFlags — extra flags passed to cargo test
• checkFlags — flags appended to the test command. Use --skip to disable specific tests:

  checkFlags = [
    "--skip=tests::network_test"
    "--skip=tests::flaky_timing"
  ];
  

Auto-Generated Tests

buildRustPackage automatically provides passthru.tests.build — a variant that re-runs with doCheck = true. User-supplied passthru.tests entries merge alongside it.

Native Dependencies

Rust crates that link C libraries need explicit inputs:

nativeBuildInputs = [ pkg-config ];
buildInputs = [ openssl zlib ];

Shell Completions

nativeBuildInputs = [ installShellFiles ];

postInstall = ''
  installShellCompletion --cmd example \
    --bash <($out/bin/example completions bash) \
    --fish <($out/bin/example completions fish) \
    --zsh <($out/bin/example completions zsh)
'';

Guard with build platform check when cross-compiling:

postInstall = lib.optionalString (stdenv.hostPlatform.emulatorAvailable buildPackages) ''
  installShellCompletion ...
'';

Complete Example

{
  lib,
  rustPlatform,
  fetchFromGitHub,
  pkg-config,
  erlang,
  git,
}:

rustPlatform.buildRustPackage (finalAttrs: {
  pname = "gleam";
  version = "1.18.1";

  src = fetchFromGitHub {
    owner = "gleam-lang";
    repo = "gleam";
    tag = "v${finalAttrs.version}";
    hash = "sha256-...";
  };

  cargoHash = "sha256-...";

  nativeBuildInputs = [ pkg-config erlang ];
  nativeCheckInputs = [ git ];

  checkFlags = [
    "--skip=tests::all_files_have_copyright_notice"
    "--skip=tests::echo::"
  ];

  meta = {
    description = "Statically typed language for the Erlang VM";
    homepage = "https://gleam.run/";
    license = lib.licenses.asl20;
    mainProgram = "gleam";
  };
})