API Documentation

mkLib

mkLib :: pkgs -> set

Creates a lib instance bound to the specified (and instantiated) pkgs set. This is a convenience escape hatch in case you want to use your own custom instantiation of nixpkgs with the overlays you may need.

mkLib (import inputs.nixpkgs { system = "armv7l-linux"; })

Note that if you wish to override a particular package without having to overlay it across all of nixpkgs, consider using overrideScope:

(mkLib pkgs).overrideScope (final: prev: {
  cargo-tarpaulin = myCustomCargoTarpaulinVersion;
})

To overlay an entire rust toolchain (e.g. cargo, rustc, clippy, rustfmt, etc.) consider using overrideToolchain.

craneLib

craneLib represents an instantiated value crated by mkLib above.

craneLib.appendCrateRegistries

appendCrateRegistries :: [registry mapping] -> new lib

Creates a new lib instance which will make additional registries available for use when downloading crate sources. Each entry can be defined using:

• registryFromDownloadUrl: if you know the exact dl URL as defined in the registry's config.json file
• registryFromGitIndex: if you would like the download URL to be inferred from the index's source directly.
• registryFromSparse: if you would like the download URL to be inferred from the index's source directly, and the index is a sparse index.

See the documentation on each function for more specifics.

newLib = craneLib.appendCrateRegistries [
  (craneLib.registryFromDownloadUrl {
    indexUrl = "https://github.com/rust-lang/crates.io-index";
    dl = "https://static.crates.io/crates";
    fetchurlExtraArgs = {};
  })

  # Or, alternatively
  (craneLib.registryFromGitIndex {
    indexUrl = "https://github.com/Hirevo/alexandrie-index";
    rev = "90df25daf291d402d1ded8c32c23d5e1498c6725";
    fetchurlExtraArgs = {};
  })

  # Or even
  (lib.registryFromSparse {
    indexUrl = "https://index.crates.io/config.json";
    configSha256 = "1cxgzdm1ipqmgwnq7kgym92axna7pfyhgfla63vl7dvydwn3m52v";
    fetchurlExtraArgs = {};
  })
];

craneLib.buildDepsOnly

buildDepsOnly :: set -> drv

Create a derivation which will only build all dependencies of a cargo workspace.

Useful for splitting up cargo projects into two derivations: one which only builds dependencies and needs to be rebuilt when a Cargo.lock file changes, and another which inherits the cargo artifacts from the first and (quickly) builds just the application itself.

The exact cargo commands being run (or the arguments passed into it) can be easily updated to suit your needs. By default all artifacts from running cargo {check,build,test} will be cached.

In addition to all default and overridden values being set as documented below, all derivation attributes are delegated to mkCargoDerivation, and can be used to influence its behavior.

• cargoArtifacts: set to null since this is our entry point for generating cargo artifacts
• doInstallCargoArtifacts: set to true
• pnameSuffix: set to "-deps"
• src: set to the result of mkDummySrc after applying the arguments set. This ensures that we do not need to rebuild the cargo artifacts derivation whenever the application source changes.
• CRANE_BUILD_DEPS_ONLY is exported as an environment variable, in case this is handy for scripts or hooks which may want to customize how they run

Optional attributes

• buildPhaseCargoCommand: A command to run during the derivation's build phase. Pre and post build hooks will automatically be run.
  • Default value: "${cargoCheckCommand} ${cargoExtraArgs}\n${cargoBuildCommand} ${cargoExtraArgs}"
• cargoBuildCommand: A cargo (build) invocation to run during the derivation's build phase
  • Default value: "cargo build --profile release"
    • CARGO_PROFILE can be set on the derivation to alter which cargo profile is selected; setting it to "" will omit specifying a profile altogether.
• cargoCheckCommand: A cargo (check) invocation to run during the derivation's build phase (in order to cache additional artifacts)
  • Default value: "cargo check --profile release ${cargoCheckExtraArgs}"
    • CARGO_PROFILE can be set on the derivation to alter which cargo profile is selected; setting it to "" will omit specifying a profile altogether.
• cargoCheckExtraArgs: additional flags to be passed in the cargoCheckCommand invocation
  • Default value: "--all-targets" if doCheck is set to true, "" otherwise
• cargoExtraArgs: additional flags to be passed in the cargo invocation (e.g. enabling specific features)
  • Default value: "--locked"
• cargoTestCommand: A cargo invocation to run during the derivation's check phase
  • Default value: "cargo test --profile release"
    • CARGO_PROFILE can be set on the derivation to alter which cargo profile is selected; setting it to "" will omit specifying a profile altogether.
• cargoTestExtraArgs: additional flags to be passed in the cargoTestCommand invocation (e.g. enabling specific tests)
  • Default value: "--no-run"
• cargoVendorDir: A path (or derivation) of vendored cargo sources which can be consumed without network access. Directory structure should basically follow the output of cargo vendor.
  • Default value: the result of vendorCargoDeps after applying the arguments set (with the respective default values). Note if dummySrc is specified, it will be used as the src passed into vendorCargoDeps
• checkPhaseCargoCommand: A command to run during the derivation's check phase. Pre and post check hooks will automatically be run.
  • Default value: "${cargoTestCommand} ${cargoExtraArgs}"
• doCheck: whether the derivation's check phase should be run
  • Default value: true
• dummySrc: the "dummy" source to use when building this derivation. Automatically derived if not passed in
  • Default value: mkDummySrc args.src
• pname: package name of the derivation
  • Default value: inherited from calling crateNameFromCargoToml. Note if dummySrc is specified, it will be used as the src passed into crateNameFromCargoToml
• version: version of the derivation
  • Default value: inherited from calling crateNameFromCargoToml. Note if dummySrc is specified, it will be used as the src passed into crateNameFromCargoToml

Remove attributes

The following attributes will be removed before being lowered to mkCargoDerivation. If you absolutely need these attributes present as environment variables during the build, you can bring them back via .overrideAttrs.

• cargoBuildCommand
• cargoCheckCommand
• cargoCheckExtraArgs
• cargoExtraArgs
• cargoTestCommand
• cargoTestExtraArgs
• dummySrc
• outputHashes
• outputs

craneLib.buildPackage

buildPackage :: set -> drv

A(n opinionated) version of mkCargoDerivation which will install to the output any binaries which were built by cargo in this invocation. All options understood by mkCargoDerivation apply here as well, with the only difference being some additional book keeping necessary to log cargo's results and subsequently install from that log.

Note that only bin, cdylib, dylib, and staticlib, targets will be installed by default (namely rlib targets will be ignored), though it is possible to adjust the behavior by changing the installPhaseCommand or registering additional install hooks.

Optional attributes

• buildPhaseCargoCommand: A command to run during the derivation's build phase. Pre and post build hooks will automatically be run.
  • Default value: cargoBuildCommand will be invoked along with cargoExtraArgs passed in, except cargo's build steps will also be captured and written to a log so that it can be used to find the build binaries.
  • Note that the default install hook assumes that the build phase will create a log of cargo's build results. If you wish to customize this command completely, make sure that cargo is run with --message-format json-render-diagnostics and the standard output captured and saved to a file. The cargoBuildLog shell variable should point to this log.
• cargoArtifacts: A path (or derivation) which contains an existing cargo target directory, which will be reused at the start of the derivation. Useful for caching incremental cargo builds.
  • Default value: the result of buildDepsOnly after applying the arguments set (with the respective default values).
  • installPhase and installPhaseCommand will be removed, and no installation hooks will be run
• cargoBuildCommand: A cargo invocation to run during the derivation's build phase
  • Default value: "cargo build --profile release"
    • CARGO_PROFILE can be set on the derivation to alter which cargo profile is selected; setting it to "" will omit specifying a profile altogether.
• cargoExtraArgs: additional flags to be passed in the cargo invocation (e.g. enabling specific features)
  • Default value: "--locked"
• cargoTestCommand: A cargo invocation to run during the derivation's check phase
  • Default value: "cargo test --profile release"
    • CARGO_PROFILE can be set on the derivation to alter which cargo profile is selected; setting it to "" will omit specifying a profile altogether.
• cargoTestExtraArgs: additional flags to be passed in the cargoTestCommand invocation (e.g. enabling specific tests)
  • Default value: ""
• doCheck: whether the derivation's check phase should be run
  • Default value: true
• doInstallCargoArtifacts: controls whether cargo's target directory should be copied as an output
  • Default value: false
• installPhaseCommand: the command(s) which are expected to install the derivation's outputs.
  • Default value: will look for a temporary installation directory created by installFromCargoBuildLogHook and then install all of its contents

Remove attributes

The following attributes will be removed before being lowered to mkCargoDerivation. If you absolutely need these attributes present as environment variables during the build, you can bring them back via .overrideAttrs.

• cargoBuildCommand
• cargoExtraArgs
• cargoTestCommand
• cargoTestExtraArgs
• outputHashes

Native build dependencies and included hooks

The following hooks are automatically added as native build inputs:

• installFromCargoBuildLogHook
• removeReferencesToRustToolchainHook
• removeReferencesToVendoredSourcesHook

craneLib.buildTrunkPackage

buildTrunkPackage :: set -> drv

Create a derivation which will build a distributable directory for a WASM application.

Except where noted below, all derivation attributes are delegated to mkCargoDerivation, and can be used to influence its behavior.

Optional attributes

• buildPhaseCargoCommand: A command to run during the derivation's build phase. Pre and post build hooks will automatically be run.
  • Default value: trunk build will be invoked along with trunkExtraArgs, trunkExtraBuildArgs, and trunkIndexpath passed in. If $CARGO_PROFILE is set to release then the --release flag will also be set for the build
• cargoArtifacts: A path (or derivation) which contains an existing cargo target directory, which will be reused at the start of the derivation. Useful for caching incremental cargo builds.
  • Default value: the result of buildDepsOnly after applying the arguments set (with the respective default values).
  • CARGO_BUILD_TARGET will be set to "wasm32-unknown-unknown" if not specified.
  • doCheck will be set to false if not specified.
  • installPhase and installPhaseCommand will be removed (in favor of their default values provided by buildDepsOnly)
• installPhaseCommand: the command(s) which are expected to install the derivation's outputs.
  • Default value: will install trunk's dist output directory
• trunkExtraArgs pass additional arguments to trunk
  • Default value: ""
• trunkExtraBuildArgs pass additional arguments to trunk build
  • Default value: ""
• trunkIndexPath A path to the index.html of your trunk project
  • Default value: "./index.html"
• wasm-bindgen-cli The package used to satisfy the wasm-bindgen-cli dependency of trunk, the version used here must match the version of wasm-bindgen in the Cargo.lock file of your project exactly.
  • Default value: pkgs.wasm-bindgen-cli

Remove attributes

The following attributes will be removed before being lowered to mkCargoDerivation. If you absolutely need these attributes present as environment variables during the build, you can bring them back via .overrideAttrs.

• trunkExtraArgs
• trunkExtraBuildArgs
• trunkIndexPath

Native build dependencies and included hooks

The following hooks are automatically added as native build inputs:

• binaryen
• dart-sass
• trunk
• removeReferencesToRustToolchainHook
• removeReferencesToVendoredSourcesHook

craneLib.cargoAudit

cargoAudit :: set -> drv

Create a derivation which will run a cargo audit invocation in a cargo workspace.

Except where noted below, all derivation attributes are delegated to mkCargoDerivation, and can be used to influence its behavior.

• buildPhaseCargoCommand will be set to run cargo audit -n -d ${advisory-db} in the workspace.
• cargoArtifacts will be set to null as they are not needed
• cargoVendorDir will be set to null as it is not needed
• doInstallCargoArtifacts is disabled
• pnameSuffix will be set to "-audit"
• src will be filtered to only keep Cargo.lock files

Required attributes

• advisory-db: A path (or derivation) which contains the advisory database
  • It is possible to track the advisory database as a flake input and avoid having to manually update hashes or specific revisions to check out
• src: The project source to audit, it must contain a Cargo.lock file
  • Note that the source will internally be filtered to omit any files besides Cargo.lock. This avoids having to audit the project again until either the advisory database or the dependencies change.

Optional attributes

• cargoAuditExtraArgs: additional flags to be passed in the cargo-audit invocation
  • Default value: "--ignore yanked"
• pname: the name of the derivation; will not be introspected from a Cargo.toml file
  • Default value: "crate"
• version: the version of the derivation, will not be introspected from a Cargo.toml file
  • Default value: "0.0.0"

Native build dependencies

The cargo-audit package is automatically appended as a native build input to any other nativeBuildInputs specified by the caller.

Remove attributes

The following attributes will be removed before being lowered to mkCargoDerivation. If you absolutely need these attributes present as environment variables during the build, you can bring them back via .overrideAttrs.

• cargoAuditExtraArgs

craneLib.cargoDeny

cargoDeny :: set -> drv

Create a derivation which will run a cargo deny invocation in a cargo workspace.

Note that although cargo deny can serve as a replacement for cargo audit, craneLib.cargoDeny does not expose this functionality because cargo deny requires the full source tree, rather than working from just the Cargo.lock file, meaning it will be re-run when any source file changes, rather than only when dependencies change.

Except where noted below, all derivation attributes are delegated to mkCargoDerivation, and can be used to influence its behavior.

• buildPhaseCargoCommand will be set to run cargo --offline $cargoExtraArgs deny $cargoDenyExtraArgs check $cargoDenyChecks in the workspace.
• cargoArtifacts will be set to null
• doInstallCargoArtifacts will be set to false
• pnameSuffix will be set to "-deny"

Optional attributes

• cargoDenyChecks: check types to run
  • Default value: "bans licenses sources"
• cargoDenyExtraArgs: additional flags to be passed in the cargo-deny invocation
  • Default value: ""
• cargoExtraArgs: additional flags to be passed in the cargo invocation
  • Default value: ""

Native build dependencies

The cargo-deny package is automatically appended as a native build input to any other nativeBuildInputs specified by the caller.

Remove attributes

The following attributes will be removed before being lowered to mkCargoDerivation. If you absolutely need these attributes present as environment variables during the build, you can bring them back via .overrideAttrs.

• cargoDenyExtraArgs
• cargoExtraArgs

craneLib.cargoBuild

cargoBuild :: set -> drv

Create a derivation which will run a cargo build invocation in a cargo workspace. Consider using buildPackage if all you need is to build the workspace and install the resulting application binaries.

Except where noted below, all derivation attributes are delegated to mkCargoDerivation, and can be used to influence its behavior.

• buildPhaseCargoCommand will be set to run cargo build --profile release for the workspace.
  • CARGO_PROFILE can be set on the derivation to alter which cargo profile is selected; setting it to "" will omit specifying a profile altogether.
• pnameSuffix will be set to "-build"

Required attributes

• cargoArtifacts: A path (or derivation) which contains an existing cargo target directory, which will be reused at the start of the derivation. Useful for caching incremental cargo builds.
  • This can be prepared via buildDepsOnly
  • Alternatively, any cargo-based derivation which was built with doInstallCargoArtifacts = true will work as well

Optional attributes

• cargoExtraArgs: additional flags to be passed in the cargo invocation (e.g. enabling specific features)
  • Default value: "--locked"

Remove attributes

The following attributes will be removed before being lowered to mkCargoDerivation. If you absolutely need these attributes present as environment variables during the build, you can bring them back via .overrideAttrs.

• cargoExtraArgs

craneLib.cargoClippy

cargoClippy :: set -> drv

Create a derivation which will run a cargo clippy invocation in a cargo workspace.

Except where noted below, all derivation attributes are delegated to mkCargoDerivation, and can be used to influence its behavior.

• buildPhaseCargoCommand will be set to run cargo clippy --profile release for the workspace.
  • CARGO_PROFILE can be set on the derivation to alter which cargo profile is selected; setting it to "" will omit specifying a profile altogether.
• pnameSuffix will be set to "-clippy"

Required attributes

• cargoArtifacts: A path (or derivation) which contains an existing cargo target directory, which will be reused at the start of the derivation. Useful for caching incremental cargo builds.
  • This can be prepared via buildDepsOnly
  • Alternatively, any cargo-based derivation which was built with doInstallCargoArtifacts = true will work as well

Optional attributes

• cargoClippyExtraArgs: additional flags to be passed in the clippy invocation (e.g. deny specific lints)
  • Default value: "--all-targets"
• cargoExtraArgs: additional flags to be passed in the cargo invocation (e.g. enabling specific features)
  • Default value: "--locked"

Native build dependencies

The clippy package is automatically appended as a native build input to any other nativeBuildInputs specified by the caller.

Remove attributes

The following attributes will be removed before being lowered to mkCargoDerivation. If you absolutely need these attributes present as environment variables during the build, you can bring them back via .overrideAttrs.

• cargoClippyExtraArgs
• cargoExtraArgs

craneLib.cargoDoc

cargoDoc :: set -> drv

Create a derivation which will run a cargo doc invocation in a cargo workspace.

Except where noted below, all derivation attributes are delegated to mkCargoDerivation, and can be used to influence its behavior.

• buildPhaseCargoCommand will be set to run cargo doc --profile release for the workspace.
  • CARGO_PROFILE can be set on the derivation to alter which cargo profile is selected; setting it to "" will omit specifying a profile altogether.
• doInstallCargoArtifacts will default to false if not specified
• pnameSuffix will be set to "-doc"

Required attributes

• cargoArtifacts: A path (or derivation) which contains an existing cargo target directory, which will be reused at the start of the derivation. Useful for caching incremental cargo builds.
  • This can be prepared via buildDepsOnly
  • Alternatively, any cargo-based derivation which was built with doInstallCargoArtifacts = true will work as well

Optional attributes

• cargoDocExtraArgs: additional flags to be passed in the rustdoc invocation (e.g. deny specific lints)
  • Default value: "--no-deps"
• cargoExtraArgs: additional flags to be passed in the cargo invocation (e.g. enabling specific features)
  • Default value: "--locked"
• docInstallRoot: defines the exact directory to install to $out/share, useful for overriding when compiling different targets. By default will honor $CARGO_TARGET_DIR (or default to ./target if not set) and $CARGO_BUILD_TARGET (if set).
  • Default value: "${CARGO_TARGET_DIR:-target}/${CARGO_BUILD_TARGET:-}/doc" if such a directory exists, otherwise falls back to "${CARGO_TARGET_DIR:-target}/doc"

Remove attributes

The following attributes will be removed before being lowered to mkCargoDerivation. If you absolutely need these attributes present as environment variables during the build, you can bring them back via .overrideAttrs.

• cargoDocExtraArgs
• cargoExtraArgs

craneLib.cargoDocTest

cargoDocTest :: set -> drv

Create a derivation which will run a cargo test --doc invocation in a cargo workspace. To run all or any tests for a workspace, consider cargoTest.

Except where noted below, all derivation attributes are delegated to mkCargoDerivation, and can be used to influence its behavior.

• buildPhaseCargoCommand will be set to run cargo test --profile release in the workspace.
  • CARGO_PROFILE can be set on the derivation to alter which cargo profile is selected; setting it to "" will omit specifying a profile altogether.
• pnameSuffix will be set to "-doctest"

Optional attributes

• cargoExtraArgs: additional flags to be passed in the cargo invocation
  • Default value: "--locked"
• cargoTestExtraArgs: additional flags to be passed in the cargo invocation
  • Default value: ""

craneLib.cargoFmt

cargoFmt :: set -> drv

Create a derivation which will run a cargo fmt invocation in a cargo workspace.

Except where noted below, all derivation attributes are delegated to mkCargoDerivation, and can be used to influence its behavior.

• buildPhaseCargoCommand will be set to run cargo fmt (in check mode) in the workspace.
• cargoArtifacts is disabled/cleared
• cargoVendorDir is disabled/cleared
• pnameSuffix will be set to "-fmt"

Optional attributes

• cargoExtraArgs: additional flags to be passed in the cargo invocation
  • Default value: ""
• rustFmtExtraArgs: additional flags to be passed in the rustfmt invocation
  • Default value: ""

Native build dependencies

The rustfmt package is automatically appended as a native build input to any other nativeBuildInputs specified by the caller.

Remove attributes

The following attributes will be removed before being lowered to mkCargoDerivation. If you absolutely need these attributes present as environment variables during the build, you can bring them back via .overrideAttrs.

• cargoExtraArgs
• rustFmtExtraArgs

craneLib.taploFmt

taploFmt :: set -> drv

Create a derivation which will run a taplo fmt invocation in a cargo workspace.

Except where noted below, all derivation attributes are delegated to mkCargoDerivation, and can be used to influence its behavior.

• buildPhaseCargoCommand will be set to run taplo fmt (in check mode) in the workspace.
• cargoArtifacts is disabled/cleared
• cargoVendorDir is disabled/cleared
• pnameSuffix will be set to "-tomlfmt"

Optional attributes

• taploExtraArgs: additional flags to be passed in the taplo invocation
  • Default value: ""

taplo command line options for setting taploExtraArgs and configuration options for taplo.toml config files can be found in the Command Line and Configuration sections of the taplo documentation.

Native build dependencies

The taplo package is automatically appended as a native build input to any other nativeBuildInputs specified by the caller.

Remove attributes

The following attributes will be removed before being lowered to mkCargoDerivation. If you absolutely need these attributes present as environment variables during the build, you can bring them back via .overrideAttrs.

• taploExtraArgs

craneLib.cargoLlvmCov

cargoLlvmCov :: set -> drv

Create a derivation which will run a cargo llvm-cov invocation in a cargo workspace.

Except where noted below, all derivation attributes are delegated to mkCargoDerivation, and can be used to influence its behavior.

• buildPhaseCargoCommand will be set to run cargo llvm-cov test --release in the workspace.
• installPhaseCommand will be set to "", as the default settings creates a file instead of directory at $out.
• doInstallCargoArtifacts will be set to false for the same reason as installPhaseCommand
• pnameSuffix will be set to "-llvm-cov"

Required attributes

• cargoArtifacts: A path (or derivation) which contains an existing cargo target directory, which will be reused at the start of the derivation. Useful for caching incremental cargo builds.
  • This can be prepared via buildDepsOnly
  • Alternatively, any cargo-based derivation which was built with doInstallCargoArtifacts = true will work as well

Optional attributes

• cargoExtraArgs: additional flags to be passed in the cargo invocation
  • Default value: "--locked"
• cargoLlvmCovCommand: cargo-llvm-cov command to run
  • Default value: "test"
• cargoLlvmCovExtraArgs: additional flags to be passed in the cargo llvm-cov invocation
  • Default value: "--lcov --output-path $out"

Native build dependencies

The cargo-llvm-cov package is automatically appended as a native build input to any other nativeBuildInputs specified by the caller.

Note that this would require the llvm-tools-preview component for the Rust toolchain, which you would need to provide yourself using fenix or rust-overlay.

Remove attributes

The following attributes will be removed before being lowered to mkCargoDerivation. If you absolutely need these attributes present as environment variables during the build, you can bring them back via .overrideAttrs.

• cargoExtraArgs
• cargoLlvmCovCommand
• cargoLlvmCovExtraArgs

craneLib.cargoNextest

cargoNextest :: set -> drv

Create a derivation which will run a cargo nextest invocation in a cargo workspace. Note that cargo nextest doesn't run doctests, so you may also want to build a cargoDocTest derivation.

Except where noted below, all derivation attributes are delegated to mkCargoDerivation, and can be used to influence its behavior.

• checkPhaseCargoCommand will be set to run cargo nextest run --profile release for the workspace.
  • CARGO_PROFILE can be set on the derivation to alter which cargo profile is selected; setting it to "" will omit specifying a profile altogether.
• pnameSuffix will be set to "-nextest" and may include partition numbers

Required attributes

• cargoArtifacts: A path (or derivation) which contains an existing cargo target directory, which will be reused at the start of the derivation. Useful for caching incremental cargo builds.
  • This can be prepared via buildDepsOnly
  • Alternatively, any cargo-based derivation which was built with doInstallCargoArtifacts = true will work as well

Optional attributes

• buildPhaseCargoCommand, unless specified, will be set to print the nextest version
• cargoExtraArgs: additional flags to be passed in the cargo invocation (e.g. enabling specific features)
  • Default value: ""
• cargoLlvmCovExtraArgs: additional flags to be passed in the cargo llvm-cov invocation
  • Default value: "--lcov --output-path $out/coverage"
• cargoNextestExtraArgs: additional flags to be passed in the nextest invocation (e.g. specifying a profile)
  • Default value: ""
  • Note that all flags from cargo test are supported.
• cargoNextestPartitionsExtraArgs: additional flags to be passed in the nextest partition invocation
  • Default value: ""
• partitions: The number of separate nextest partitions to run. Useful if the test suite takes a long time and can be parallelized across multiple build nodes.
  • Default value: 1
• partitionType: The kind of nextest partition to run (e.g. "count" or "hash" based).
  • Default value: "count"
• withLlvmCov: Whether or not to run nextest through cargo llvm-cov
  • Default value: false
  • Note that setting withLlvmCov = true; is not currently supported if partitions > 1.

Native build dependencies

The cargo-nextest package is automatically appended as a native build input to any other nativeBuildInputs specified by the caller.

Remove attributes

The following attributes will be removed before being lowered to mkCargoDerivation. If you absolutely need these attributes present as environment variables during the build, you can bring them back via .overrideAttrs.

• cargoExtraArgs
• cargoLlvmCovExtraArgs
• cargoNextestExtraArgs
• cargoNextestPartitionsExtraArgs
• partitions
• partitionType
• withLlvmCov

craneLib.cargoTarpaulin

cargoTarpaulin :: set -> drv

Create a derivation which will run a cargo tarpaulin invocation in a cargo workspace.

Except where noted below, all derivation attributes are delegated to mkCargoDerivation, and can be used to influence its behavior.

• buildPhaseCargoCommand will be set to run cargo tarpaulin --profile release in the workspace.
  • CARGO_PROFILE can be set on the derivation to alter which cargo profile is selected; setting it to "" will omit specifying a profile altogether.
• pnameSuffix will be set to "-tarpaulin"

Required attributes

• cargoArtifacts: A path (or derivation) which contains an existing cargo target directory, which will be reused at the start of the derivation. Useful for caching incremental cargo builds.
  • This can be prepared via buildDepsOnly
  • Alternatively, any cargo-based derivation which was built with doInstallCargoArtifacts = true will work as well

Optional attributes

• cargoExtraArgs: additional flags to be passed in the cargo invocation
  • Default value: ""
• cargoTarpaulinExtraArgs: additional flags to be passed in the cargo tarpaulin invocation
  • Default value: "--skip-clean --out xml --output-dir $out"
• doNotLinkInheritedArtifacts will be set to true if not specified.

Native build dependencies

The cargo-tarpaulin package is automatically appended as a native build input to any other nativeBuildInputs specified by the caller.

Remove attributes

The following attributes will be removed before being lowered to mkCargoDerivation. If you absolutely need these attributes present as environment variables during the build, you can bring them back via .overrideAttrs.

• cargoExtraArgs
• cargoTarpaulinExtraArgs

craneLib.cargoTest

cargoTest :: set -> drv

Create a derivation which will run a cargo test invocation in a cargo workspace.

Except where noted below, all derivation attributes are delegated to mkCargoDerivation, and can be used to influence its behavior.

• buildPhaseCargoCommand will be set to run cargo test --profile release in the workspace.
  • CARGO_PROFILE can be set on the derivation to alter which cargo profile is selected; setting it to "" will omit specifying a profile altogether.
• pnameSuffix will be set to "-test"

Optional attributes

• cargoExtraArgs: additional flags to be passed in the cargo invocation
  • Default value: "--locked"
• cargoTestExtraArgs: additional flags to be passed in the cargo invocation
  • Default value: ""

Remove attributes

The following attributes will be removed before being lowered to mkCargoDerivation. If you absolutely need these attributes present as environment variables during the build, you can bring them back via .overrideAttrs.

• cargoExtraArgs
• cargoTestExtraArgs

Remove attributes

The following attributes will be removed before being lowered to mkCargoDerivation. If you absolutely need these attributes present as environment variables during the build, you can bring them back via .overrideAttrs.

• cargoExtraArgs
• cargoTestExtraArgs

craneLib.cleanCargoSource

cleanCargoSource :: path or drv -> drv

Cleans a source tree to omit things like version control directories as well omit any non-Rust/non-cargo related files. Useful to avoid rebuilding a project when unrelated files are changed (e.g. flake.nix or any other nix files).

The final output will be cleaned by both cleanSource (from nixpkgs) and craneLib.filterCargoSources. See each of them for more details on which files are kept.

If it is necessary to customize which files are kept, a custom filter can be written (which may want to also call craneLib.filterCargoSources) to achieve the desired behavior.

craneLib.cleanCargoSource ./.

craneLib.cleanCargoToml

cleanCargoToml :: set -> set

Cleans all definitions from a Cargo.toml file which are irrelevant for a minimal build of a package's dependencies. See mkDummySrc for more information on how the result is applied.

In general, the following types of attributes are kept from the original input:

• basic package definitions (like name and version)
• dependency definitions
• feature definitions
• workspace definitions
• anything pertaining to project structure (like bin/lib targets, tests, etc.)

craneLib.cleanCargoToml { cargoToml = ./Cargo.toml; }
# { dependencies = { byteorder = "*"; }; package = { edition = "2021"; name = "simple"; version = "0.1.0"; }; }

Input attributes

• cargoToml: a path to a Cargo.toml file
• cargoTomlContents: the contents of a Cargo.toml file as a string

At least one of the above attributes must be specified, or an error will be raised during evaluation.

craneLib.crateNameFromCargoToml

crateNameFromCargoToml :: set -> set

Extract a crate's name and version from its Cargo.toml file.

The resulting pname attribute will be populated with the value of the Cargo.toml's (top-level) attributes in the following order, where the first attribute (with a string value) will be chosen:

1. package.metadata.crane.name
2. package.name
3. workspace.metadata.crane.name
4. (Deprecated) workspace.package.name
5. Otherwise a placeholder name will be used

The resulting version attribute will be populated with the value of the Cargo.toml's (top-level) attributes in the following order, where the first attribute (with a string value) will be chosen:

1. package.version
2. workspace.package.version
3. Otherwise a placeholder version will be used

Note that only the root Cargo.toml of the specified source will be checked. Directories will not be crawled to resolve potential workspace inheritance.

craneLib.crateNameFromCargoToml { cargoToml = ./Cargo.toml; }
# { pname = "simple"; version = "0.1.0"; }

craneLib.crateRegistries

crateRegistries :: set

A set of crate registries made available for use in downloading crate sources. The keys are registry URLs as used in the Cargo.lock file (e.g. "registry+https://...") and the values are the download URL for that registry, including any placeholder values cargo is expected to populate for downloads.

This definition can be updated via appendCrateRegistries.

Input attributes

• src: a directory which includes a Cargo.toml file at its root.
• cargoToml: a path to a Cargo.toml file
• cargoTomlContents: the contents of a Cargo.toml file as a string

At least one of the above attributes must be specified, or an error will be raised during evaluation.

Output attributes

• pname: the name of the crate
  • Default value: "cargo-package" if the specified Cargo.toml file did not include a name
• version: the version of the crate
  • Default value: "0.0.1" if the specified Cargo.toml file did not include a version

craneLib.devShell

devShell :: set -> drv

A thin wrapper around pkgs.mkShell for creating development shells for use with nix develop (see “Local Development”). Except where noted below, all derivation attributes are passed straight through, so any mkShell behavior can be used as expected: namely, all key-value pairs other than those mkShell consumes will be set as environment variables in the resulting shell.

Note that the current toolchain's cargo, clippy, rustc, and rustfmt packages will automatically be added to the devShell.

Optional attributes

• checks: A set of checks to inherit inputs from, typically self.checks.${system}. Build inputs from the values in this attribute set are added to the created shell environment for interactive use.
• inputsFrom: A list of extra packages to inherit inputs from. Note that these packages are not added to the result environment; use packages for that.
• packages: A list of extra packages to add to the created shell environment.
• shellHook: A string of bash statements that will be executed when the shell is entered with nix develop.

See the quick start example for usage in a flake.nix file.

craneLib.devShell {
  checks = self.checks.${system};

  packages = [
    pkgs.ripgrep
  ];

  # Set a `cargo-nextest` profile:
  NEXTEST_PROFILE = "local";
}

craneLib.devShell {
  checks = {
    my-package-clippy = craneLib.cargoClippy commonArgs;
    my-package-doc = craneLib.cargoDoc commonArgs;
    my-package-nextest = craneLib.cargoNextest commonArgs;
  };
}

Note that it is possible to override the underlying mkShell (for example to customize the build environment further) like so:

let
  moldDevShell = craneLib.devShell.override {
    # For example, use the mold linker
    mkShell = pkgs.mkShell.override {
      stdenv = pkgs.stdenvAdapters.useMoldLinker pkgs.stdenv;
    };
  };
in
moldDevShell {
  packages = [
    # etc...
  ];
}

craneLib.downloadCargoPackage

downloadCargoPackage :: set -> drv

Download a packaged cargo crate (e.g. from crates.io) and prepare it for vendoring.

The registry's fetchurlExtraArgs will be passed through to fetchurl when downloading the crate, making it possible to influence interacting with the registry's API if necessary.

Required input attributes

• checksum: the (sha256) checksum recorded in the Cargo.lock file
• name: the name of the crate
• source: the source key recorded in the Cargo.lock file
• version: the version of the crate

Attributes of the vendor-prep derivation

• dontBuild: true
• dontConfigure: true
• dontFixup: true
• pname: "cargo-package-" suffixed by the package name in Cargo.lock
• sourceRoot: "./crate"
• version: inherited from the package version in Cargo.lock
• unpackPhase: This phase will:
  1. run the preUnpack hook
  2. create an empty directory named ./crate
  3. unpack the crate's tarball under ./crate
  4. run the postUnpack hook
• installPhase: This phase will:
  1. run the preInstall hook
  2. move the contents of the current directory (i.e. ./crate by default) to $out
  3. populate $out/.cargo-checksum.json
  4. run the postInstall hook

craneLib.downloadCargoPackageFromGit

downloadCargoPackageFromGit :: set -> drv

Download a git repository containing a cargo crate or workspace, and prepare it any crates it contains for vendoring.

Required input attributes

• git: the URL to the repository
• rev: the exact revision to check out

Optional attributes

• allRefs: whether all git refs should be fetched in order to look for the specified rev
  • Default value: true if ref is set to null, false otherwise
• ref: the ref (i.e. branch or tag) to which rev belongs to. For branches it should be "refs/head/${branch}" and for tags it should be "refs/tags/${tag}"
  • Default value: null
• sha256: the sha256 hash of the (unpacked) download. If provided fetchgit will be used (instead of builtins.fetchGit) which allows for offline evaluations.
  • Default value: null

Attributes of the vendor-prep derivation

• depsBuildBuild: a list of the following packages:
  • cargo
  • craneUtils
  • jq
  • remarshal
  • ripgrep
• dontBuild: true
• dontConfigure: true
• dontFixup: true
• installPhase: This phase will:
  1. run the preInstall hook
  2. Prepare the current directory for vendoring by:
     • Searching for all Cargo.toml files
     • Copying their parent directory to $out/$crate (where $crate is the package name and version as defined in Cargo.toml)
     • Populating .cargo-checksum.json
     • Running crane-resolve-workspace-inheritance on the Cargo.toml
     • Note that duplicate crates (whose name and version collide) are ignored
  3. run the postInstall hook
• name: set to "cargo-git"
• src: the git repo checkout, as determined by the input parameters

craneLib.findCargoFiles

findCargoFiles :: path -> set of lists

Given a path, recursively search it for any Cargo.toml, .cargo/config or .cargo/config.toml files.

craneLib.findCargoFiles ./src
# { cargoTomls = [ "..." ]; cargoConfigs = [ "..." ]; }

craneLib.filterCargoSources

filterCargoSources :: path -> string -> bool

A source filter which when used with cleanSourceWith (from nixpkgs's lib) will retain the following files from a given source:

• Cargo files (Cargo.toml, Cargo.lock, .cargo/config.toml, .cargo/config)
• Rust files (files whose name end with .rs)
• TOML files (files whose name end with .toml)

cleanSourceWith {
  src = ./.;
  filter = craneLib.filterCargoSources;
  name = "source"; # Be reproducible, regardless of the directory name
}

Note that it is possible to compose source filters, especially if filterCargoSources omits files which are relevant to the build. For example:

let
  # Only keeps markdown files
  markdownFilter = path: _type: builtins.match ".*md$" path != null;
  markdownOrCargo = path: type:
    (markdownFilter path type) || (craneLib.filterCargoSources path type);
in
cleanSourceWith {
  src = ./.;
  filter = markdownOrCargo;
  name = "source"; # Be reproducible, regardless of the directory name
}

craneLib.fileset.cargoTomlAndLock

cargoTomlAndLock :: path -> fileset

A fileset helper which will only include any Cargo.toml and Cargo.lock files from the specified path.

craneLib.fileset.commonCargoSources

commonCargoSources :: path -> fileset

A fileset helper which will only include any files commonly used by cargo projects from the specified path. Essentially a union of:

• craneLib.fileset.cargoTomlAndLock
• craneLib.fileset.rust
• craneLib.fileset.toml

craneLib.fileset.configToml

configToml :: path -> fileset

A fileset helper which will only include config.toml files from the specified path.

Note that cargo usually only pays attention to config.toml files if they are present inside of a directory named .cargo. This fileset will contain any config.toml file, even if its parent directory is not named .cargo.

craneLib.fileset.rust

rust :: path -> fileset

A fileset helper which will only include *.rs files from the specified path.

craneLib.fileset.toml

toml :: path -> fileset

A fileset helper which will only include *.toml files from the specified path.

craneLib.mkCargoDerivation

mkCargoDerivation :: set -> drv

A thin wrapper around stdenv.mkDerivation which includes common hooks for building a derivation using cargo. Except where noted below, all derivation attributes are passed straight through, so any common derivation behavior can be used as expected: namely all key-value pairs will be set as environment variables for the derivation's build script.

This is a fairly low-level abstraction, so consider using buildPackage or cargoBuild if they fit your needs.

Required attributes

• buildPhaseCargoCommand: A command (likely a cargo invocation) to run during the derivation's build phase. Pre and post build hooks will automatically be run.
• cargoArtifacts: A path (or derivation) which contains an existing cargo target directory, which will be reused at the start of the derivation. Useful for caching incremental cargo builds.
  • This can be prepared via buildDepsOnly
  • Alternatively, any cargo-based derivation which was built with doInstallCargoArtifacts = true will work as well

Optional attributes

• buildPhase: the commands used by the build phase of the derivation
  • Default value: the build phase will run preBuild hooks, print the cargo version, log and evaluate buildPhaseCargoCommand, and run postBuild hooks
• cargoLock: if set will be passed through to the derivation and the path it points to will be copied as the workspace Cargo.lock
  • Unset by default
• cargoLockContents: if set and cargoLock is missing or null, its value will be written as the workspace Cargo.lock
  • Unset by default
• cargoLockParsed: if set and both cargoLock and cargoLockContents are missing or null, its value will be serialized as TOML and the result written as the workspace Cargo.lock
  • Unset by default
• cargoVendorDir: A path (or derivation) of vendored cargo sources which can be consumed without network access. Directory structure should basically follow the output of cargo vendor.
  • Default value: the result of vendorCargoDeps after applying the arguments set (with the respective default values)
• checkPhase: the commands used by the check phase of the derivation
  • Default value: the check phase will run preCheck hooks, log and evaluate checkPhaseCargoCommand, and run postCheck hooks
• checkPhaseCargoCommand: A command (likely a cargo invocation) to run during the derivation's check phase. Pre and post check hooks will automatically be run.
  • Default value: ""
• configurePhase: the commands used by the configure phase of the derivation
  • Default value: the configure phase will run preConfigureHooks hooks, then run postConfigure hooks
• doIncludeCrossToolchainEnv: enables the default configuration of the cross-compilation toolchain using mkCrossToolchainEnv. Useful if you want to perform this configuration yourself.
  • Default value: true
• doInstallCargoArtifacts: controls whether cargo's target directory should be copied as an output
  • Default value: true
• installPhase: the commands used by the install phase of the derivation
  • Default value: the install phase will run preInstall hooks, log and evaluate installPhaseCommand, and run postInstall hooks
• installPhaseCommand: the command(s) which are expected to install the derivation's outputs.
  • Default value: "mkdir -p $out"
  • By default an output directory is created such that any other postInstall hooks can successfully run. Consider overriding this value with an appropriate installation commands for the package being built.
• pname: the name of the derivation
  • Default value: the package name listed in Cargo.toml
• pnameSuffix: a suffix appended to pname
  • Default value: ""
• stdenv: a function to select the standard build environment to use for this derivation. For backwards compatibility a non-function value (i.e. stdenv = pkgs.stdenv;) will still be accepted.
  • Default value: p: p.stdenv
• version: the version of the derivation
  • Default value: the version listed in Cargo.toml

Remove attributes

The following attributes will be removed before being lowered to stdenv.mkDerivation. If you absolutely need these attributes present as environment variables during the build, you can bring them back via .overrideAttrs.

• buildPhaseCargoCommand
• cargoLock
• cargoLockContents
• cargoLockParsed
• checkPhaseCargoCommand
• installPhaseCommand
• outputHashes
• pnameSuffix
• stdenv

Native build dependencies and included hooks

The following packages and hooks are automatically appended as a native build input to any other nativeBuildInputs specified by the caller:

• cargo
• cargoHelperFunctionsHook
• configureCargoCommonVarsHook
• configureCargoVendoredDepsHook
• inheritCargoArtifactsHook
• installCargoArtifactsHook
• replaceCargoLockHook
• rustc
• rsync
• zstd

craneLib.mkCrossToolchainEnv

mkCrossToolchainEnv :: (set -> drv) -> set

A method which returns a set of derivation arguments to configure the Rust toolchain for cross compilation. This configures both the target and host toolchains, setting environment variables both for cargo as well as for the cc crate. If the given pkgs instance is not set up for cross compilation, an empty set is returned.

The input should be a function which takes an instantiation of pkgs, returning the stdenv to use for this target.

mkCrossToolchainEnv (p: p.clangStdenv)

craneLib.mkDummySrc

mkDummySrc :: set -> drv

Converts a given source directory of a cargo workspace to the smallest, most trivial form needed to build all dependencies such that their artifacts can be cached.

The actual source files of the project itself are ignored/replaced with empty programs, such that changes to the source files does not invalidate any build caches. More specifically:

• The Cargo.lock file is kept as-is
  • Any changes to it will invalidate the build cache
• Any cargo configuration files (i.e. files name config or config.toml whose parent directory is named .cargo) are kept as-is.
  • Any changes to these files will invalidate the build cache
• Any files named Cargo.toml are reduced via cleanCargoToml and the result is kept. Only the following changes will result in invalidating the build cache:
  • Any changes to listed dependencies
  • Any changes to feature definitions
  • Any changes to the workspace member metadata
  • Any changes to the [package] definition such as name and version
  • Any changes to the name or path of any target (such as benches, bins, examples, libs, or tests)
  • Any removal or new definition of a [[bin]] target, or, any removal or new definition of a file under src/bin when autolib is enabled in the Cargo.toml file (this setting is true by default)

Required attributes

• src: a source directory which should be turned into a "dummy" form

Optional attributes

• cargoLock: a path to a Cargo.lock file
  • Default value: src + /Cargo.lock
• dummyrs: a path to a file which will be used in place of all dummy rust files (e.g. main.rs, lib.rs, etc.). This can be useful to customize dummy source files (e.g. enable certain lang features for a given target).
  • Default value: an empty fn main declaration and conditionally enabled #![no_std] if the target_os cfg is set to "none" or "uefi".
• dummyBuildrs: similar to dummyrs but will only be used in place of build scripts
  • Default value: dummyrs, if specified, otherwise, an empty fn main declaration and conditionally enabled #![no_std] if the target_os cfg is set to "none" or "uefi".
• extraDummyScript: additional shell script which will be run inside the builder verbatim. Useful for customizing what the dummy sources include by running any arbitrary commands.
  • Default value: ""
  • Note that this script will run in an environment where the original source is not present as doing so would cause a rebuild if any part of the source changed. Additional files can be copied to the derivation's result, but care must be taken that the derivation only depends on (i.e. is rebuilt if) the smallest subset of the original source as required.
  • Here is an example of how to include an entire directory, in this case .cargo, but any other directory would work as well:

    let
      # The _entire_ source of the project. mkDummySrc will automatically
      # filter out irrelevant files as described above
      src = craneLib.path ./.;
    
      dotCargoOnly = lib.cleanSourceWith {
        inherit src;
        # Only keep `*/.cargo/*`
        filter = path: _type: lib.hasInfix ".cargo" path;
      };
    in
    mkDummySrc {
      inherit src;
    
      # Note that here we scope the path to only contain any `.cargo` directory
      # and its contents and not any other  directories which may exist at the
      # root of the project. Also note that the entire path is inside of the
      # `${ }` which ensures that the derivation only consumes that directory.
      # Writing `${./.}/.cargo` would incorrectly consume the entire source root,
      # and therefore rebuild everything when any file changes, which defeats
      # artifact caching.
      #
      # Also note the `--no-target-directory` flag which ensures the results are
      # copied to `$out/.cargo` instead of something like `$out/HASH-.cargo`
      extraDummyScript = ''
        cp -r ${dotCargoOnly} --no-target-directory $out/
      '';
    }
    

craneLib.overrideToolchain

overrideToolchain :: (set -> drv) -> set overrideToolchain :: drv -> set (legacy)

A convenience method to override and use tools (like cargo, clippy, rustfmt, rustc, etc.) from one specific toolchain. The input should be a single derivation which contains all the tools as binaries. For example, this can be the output of oxalica/rust-overlay.

Note that in order to best support cross compilation, overrideToolchain should be provided a function (whose argument is a cross-compilation aware version of pkgs) which constructs the toolchain:

craneLib.overrideToolchain (p: myCustomToolchainForPkgs p)

craneLib.path

path :: path -> drv

path :: set -> drv

A convenience wrapper around builtins.path which will automatically set the path's name to the workspace's package name (or a placeholder value of "source" if a name cannot be determined).

It should be used anywhere a relative path like ./. or ./.. is needed so that the result is reproducible and caches can be reused. Otherwise the store path will depend on the name of the parent directory which may cause unnecessary rebuilds.

craneLib.path ./.
# "/nix/store/wbhf6c7wiw9z53hsn487a8wswivwdw81-source"

craneLib.path ./checks/simple
# "/nix/store/s9scn97c86kqskf7yv5n2k85in5y5cmy-simple"

It is also possible to use as a drop in replacement for builtins.path:

craneLib.path {
  path = ./.;
  name = "asdf";
}
# "/nix/store/23zy3c68v789cg8sysgba0rbgbfcjfhn-asdf"

craneLib.registryFromDownloadUrl

registryFromDownloadUrl :: set -> set

Prepares a crate registry into a format that can be passed directly to appendCrateRegistries using the registry's download URL.

If the registry in question has a stable download URL (which either never changes, or it does so very infrequently), then registryFromDownloadUrl is a great and lightweight choice for including the registry. To get started, look up the config.json at the registry's root and copy the value of the dl entry.

If the registry's download endpoint changes more frequently and you would like to infer the configuration directly from a git revision, consider using registryFromGitIndex as an alternative.

If the registry needs a special way of accessing crate sources the fetchurlExtraArgs set can be used to influence the behavior of fetching the crate sources (e.g. by setting curlOptsList)

Required attributes

• dl: the value of the dl entry in the registry's config.json file
• indexUrl: an HTTP URL to the index

Optional attributes

• fetchurlExtraArgs: a set of arguments which will be passed on to the fetchurl for each crate being sourced from this registry

craneLib.registryFromDownloadUrl {
  dl = "https://static.crates.io/crates";
  indexUrl = "https://github.com/rust-lang/crates.io-index";
}
# {
#   "registry+https://github.com/rust-lang/crates.io-index" = {
#     downloadUrl = "https://static.crates.io/crates/{crate}/{version}/download";
#     fetchurlExtraArgs = {};
#   };
# }

craneLib.registryFromGitIndex

registryFromGitIndex :: set -> set

Prepares a crate registry into a format that can be passed directly to appendCrateRegistries using a revision of the registry index to infer the download URL.

Note that the specified git revision does not need to track updates to the index itself as long as the pinned revision contains the most recent version of the config.json file. In other words, this commit revision only needs to be updated if the config.json file changes.

Also note that this approach means that the contents of the entire index at the specified revision will be added to the Nix store during evaluation time, and that IFD will need to be enabled. If this is unsatisfactory, consider using registryFromDownloadUrl as a simpler alternative.

If the registry needs a special way of accessing crate sources the fetchurlExtraArgs set can be used to influence the behavior of fetching the crate sources (e.g. by setting curlOptsList)

Required attributes

• indexUrl: an HTTP URL to the index
• rev: any git revision which contains the latest config.json definition

Optional attributes

• fetchurlExtraArgs: a set of arguments which will be passed on to the fetchurl for each crate being sourced from this registry

craneLib.registryFromGitIndex {
  url = "https://github.com/Hirevo/alexandrie-index";
  rev = "90df25daf291d402d1ded8c32c23d5e1498c6725";
}
# {
#   "registry+https://github.com/Hirevo/alexandrie-index" = {
#     downloadUrl = "https://crates.polomack.eu/api/v1/crates/{crate}/{version}/download";
#     fetchurlExtraArgs = {};
#   };
# }

craneLib.registryFromSparse

registryFromSparse :: set -> set

Prepares a (sparse) crate registry into a format that can be passed directly to appendCrateRegistries using the registry's download URL.

If the registry in question has a stable download URL (which either never changes, or it does so very infrequently), then registryFromDownloadUrl is a great and lightweight choice for including the registry. To get started, download the registry's config.json and copy the value of the dl entry.

If the registry's download endpoint changes more frequently and you would like to infer the configuration directly from a git revision, consider using registryFromGitIndex as an alternative.

If the registry needs a special way of accessing crate sources (such as for authorization), the fetchurlExtraArgs set can be used to influence the behavior of fetching the crate sources (e.g. by setting curlOptsList)

Required attributes

• indexUrl: an HTTP URL to the registry's config.json
• configSha256: a sha256 hash of the contents of config.json

Optional attributes

• fetchurlExtraArgs: a set of arguments which will be passed on to the fetchurl for each crate being sourced from this registry, and to the initial query for the registry's config.json.

craneLib.registryFromSparse {
  indexUrl = "https://index.crates.io/config.json";
  configSha256 = "1cxgzdm1ipqmgwnq7kgym92axna7pfyhgfla63vl7dvydwn3m52v";
}
# {
#   "sparse+https://index.crates.io/config.json/" = {
#     downloadUrl = "https://static.crates.io/crates/{crate}/{version}/download";
#     fetchurlExtraArgs = { };
#   };
# }

craneLib.urlForCargoPackage

urlForCargoPackage :: set -> set

Returns info pertaining to the URL for downloading a particular crate if the crate's registry is configured (an error will be thrown if it is not).

The result will contain two attributes:

• url: A string representing the URL at which the crate can be fetched
• fetchurlExtraArgs: A set of attributes specific to this registry which will be passed on to the fetchurl invocation.

Required input attributes

• name: the name of the crate
• source: the source key recorded in the Cargo.lock file
• version: the version of the crate

craneLib.vendorCargoDeps

vendorCargoDeps :: set -> drv

Creates a derivation which will download all crates referenced by a Cargo.lock file, and prepare a vendored directory which cargo can use for subsequent builds without needing network access.

Each unique crate index will be vendored as its own subdirectory within the output of the derivation. A config.toml file will also be placed at the root of the output which will contain the necessary configurations to point cargo to the vendored directories (i.e. this configuration can be appended to the .cargo/config.toml definition of the project).

Input attributes

• src: a directory which includes a Cargo.lock file at its root.
• cargoLock: a path to a Cargo.lock file
• cargoLockContents: the contents of a Cargo.lock file as a string
• cargoLockParsed: the parsed contents of Cargo.lock as an attribute set

At least one of the above attributes must be specified, or an error will be raised during evaluation.

Optional attributes

• outputHashes: a mapping of package-source to the hash attribute of the (unpacked) download. Useful for supporting fully offline evaluations.
  • Default value: []
• overrideVendorCargoPackage: a function that will be called on every crate vendored from a cargo registry, which allows for modifying the derivation which will unpack the cargo tarball (e.g. to patch the crate source). It will be called with the following parameters:
  1. The Cargo.lock entry for that package (to allow conditional overrides based on the package name/version/source, etc.)
  2. The default downloadCargoPackage derivation
  • Default value: _p: drv: drv
• overrideVendorGitCheckout: a function that will be called on every unique checkout vendored from a git repository, which allows for modifying the derivation which will unpack the cargo crates found in the checkout (e.g. to patch the crate sources). It will be called with the following parameters:
  1. A list of the Cargo.lock entries for each package which shares the same repo URL and revision to checkout (to allow conditional overrides based on the repo/checkout etc.)
  2. The default downloadCargoPackageFromGit derivation
  • Default value: _ps: drv: drv

craneLib.vendorCargoRegistries

vendorCargoRegistries :: set -> set

Creates the derivations necessary to download all crates from all registries referenced by a Cargo.lock file, and prepare the vendored directories which cargo can use for subsequent builds without needing network access.

Input attributes

• lockPackages: a list of all [[package]] entries found in the project's Cargo.lock file (parsed via builtins.fromTOML)

Optional attributes

• cargoConfigs: a list of paths to all .cargo/config.toml files which may appear in the project. Ignored if registries is set.
  • Default value: []
• overrideVendorCargoPackage: a function that will be called on every crate vendored from a cargo registry, which allows for modifying the derivation which will unpack the cargo tarball (e.g. to patch the crate source). It will be called with the following parameters:
  1. The Cargo.lock entry for that package (to allow conditional overrides based on the package name/version/source, etc.)
  2. The default downloadCargoPackage derivation
  • Default value: _p: drv: drv
• registries: an attrset of registry names to their index URL. The default ("crates-io") registry need not be specified, as it will automatically be available, but it can be overridden if required.
  • Default value: if not specified, cargoConfigs will be used to identify any configured registries

Output attributes

• config: the configuration entires needed to point cargo to the vendored crates. This is intended to be appended to $CARGO_HOME/config.toml verbatim
• sources: an attribute set of all the newly created cargo sources' names to their location in the Nix store

craneLib.vendorGitDeps

vendorGitDeps :: set -> set

Creates the derivations necessary to download all crates from all git dependencies referenced by a Cargo.lock file, and prepare the vendored directories which cargo can use for subsequent builds without needing network access.

Input attributes

• lockPackages: a list of all [[package]] entries found in the project's Cargo.lock file (parsed via builtins.fromTOML)

Optional attributes

• outputHashes: a mapping of package-source to the hash attribute of the (unpacked) download. Useful for supporting fully offline evaluations.
  • Default value: []
• overrideVendorGitCheckout: a function that will be called on every unique checkout vendored from a git repository, which allows for modifying the derivation which will unpack the cargo crates found in the checkout (e.g. to patch the crate sources). It will be called with the following parameters:
  1. A list of the Cargo.lock entries for each package which shares the same repo URL and revision to checkout (to allow conditional overrides based on the repo/checkout etc.)
  2. The default downloadCargoPackageFromGit derivation
  • Default value: _ps: drv: drv

Output attributes

• config: the configuration entires needed to point cargo to the vendored sources. This is intended to be appended to $CARGO_HOME/config.toml verbatim
• sources: an attribute set of all the newly created cargo sources' names to their location in the Nix store

craneLib.vendorMultipleCargoDeps

vendorMultipleCargoDeps :: set -> drv

Creates a derivation which will download all crates referenced by several Cargo.lock files, and prepare a vendored directory which cargo can use for subsequent builds without needing network access. Duplicate packages listed in different Cargo.lock files will automatically be filtered out.

Each unique crate index will be vendored as its own subdirectory within the output of the derivation. A config.toml file will also be placed at the root of the output which will contain the necessary configurations to point cargo to the vendored directories (i.e. this configuration can be appended to the .cargo/config.toml definition of the project).

Optional attributes

• cargoConfigs: a list of paths to all .cargo/config.toml files which may appear in the project. Ignored if registries is set.
  • Default value: []
• cargoLockContentsList: a list of strings representing the contents of different Cargo.lock files to be included while vendoring. The strings will automatically be parsed during evaluation.
  • Default value: []
• cargoLockList: a list of paths to different Cargo.lock files to be included while vendoring. The paths will automatically be read and parsed during evaluation.
  • Default value: []
• cargoLockParsedList: a list of attrsets representing the parsed contents of different Cargo.lock files to be included while vendoring.
  • Default value: []
• outputHashes: a mapping of package-source to the hash attribute of the (unpacked) download. Useful for supporting fully offline evaluations.
  • Default value: []
• overrideVendorCargoPackage: a function that will be called on every crate vendored from a cargo registry, which allows for modifying the derivation which will unpack the cargo tarball (e.g. to patch the crate source). It will be called with the following parameters:
  1. The Cargo.lock entry for that package (to allow conditional overrides based on the package name/version/source, etc.)
  2. The default downloadCargoPackage derivation
  • Default value: _p: drv: drv
• overrideVendorGitCheckout: a function that will be called on every unique checkout vendored from a git repository, which allows for modifying the derivation which will unpack the cargo crates found in the checkout (e.g. to patch the crate sources). It will be called with the following parameters:
  1. A list of the Cargo.lock entries for each package which shares the same repo URL and revision to checkout (to allow conditional overrides based on the repo/checkout etc.)
  2. The default downloadCargoPackageFromGit derivation
  • Default value: _ps: drv: drv
• registries: an attrset of registry names to their index URL. The default ("crates-io") registry need not be specified, as it will automatically be available, but it can be overridden if required.
  • Default value: if not specified, cargoConfigs will be used to identify any configured registries

craneLib.writeTOML

writeTOML :: String -> String -> drv

Takes a file name and an attribute set, converts the set to a TOML document and writes it to a file with the given name.

craneLib.writeTOML "foo.toml" { foo.bar = "baz"; }
# «derivation /nix/store/...-foo.toml.drv»

Hooks

craneLib.cargoHelperFunctionsHook

Defines helper functions for internal use. It is probably not a great idea to depend on these directly as their behavior can change at any time, but it is worth documenting them just in case:

• Defines a cargo() function which will immediately invoke the cargo command found on the $PATH after echoing the exact arguments that were passed in. Useful for automatically logging all cargo invocations to the log.
• Defines a cargoWithProfile() function which will invoke cargo with the provided arguments. If $CARGO_PROFILE is set, then --profile $CARGO_PROFILE will be injected into the cargo invocation
  • Note: a default value of $CARGO_PROFILE is set via configureCargoCommonVarsHook. You can set CARGO_PROFILE = "something" in your derivation to change which profile is used, or set CARGO_PROFILE = ""; to omit it altogether.

craneLib.configureCargoCommonVarsHook

Defines configureCargoCommonVars() which will set various common cargo-related variables, such as honoring the amount of parallelism dictated by Nix, disabling incremental artifacts, etc. More specifically:

• CARGO_BUILD_INCREMENTAL is set to false if not already defined
• CARGO_BUILD_JOBS is set to $NIX_BUILD_CORES if not already defined
• CARGO_HOME is set to $PWD/.cargo-home if not already defined.
  • The directory that CARGO_HOME points to will be created
• CARGO_PROFILE is set to release if not already defined.
  • Note that this is is used internally specify a cargo profile (e.g. cargo build --profile release) and not something natively understood by cargo.
• RUST_TEST_THREADS is set to $NIX_BUILD_CORES if not already defined

Automatic behavior: runs as a post-patch hook

craneLib.configureCargoVendoredDepsHook

Defines configureCargoVendoredDeps() which will prepare cargo to use a directory of vendored crate sources. It takes two positional arguments:

1. a path to the vendored sources
   • If not specified, the value of $cargoVendorDir will be used
   • If cargoVendorDir is not specified, an error will be raised
2. a path to a cargo config file to modify
   • If not specified, the value of $CARGO_HOME/config.toml will be used
   • This cargo config file will be appended with a stanza which will instruct cargo to use the vendored sources (instead of downloading the sources directly) as follows:
     • If the vendored directory path contains a file named config.toml, then its contents will be appended to the specified cargo config path.
     • Otherwise the entire vendored directory path will be treated as if it only vendors the crates.io index and will be configured as such.

Automatic behavior: if cargoVendorDir is set, then configureCargoVendoredDeps "$cargoVendorDir" "$CARGO_HOME/config.toml" will be run as a pre configure hook.

craneLib.craneLib

A self-reference to the crane lib instance.

craneLib.inheritCargoArtifactsHook

Defines inheritCargoArtifacts() which will pre-populate cargo's artifact directory using a previous derivation. It takes two positional arguments:

1. a path to the previously prepared artifacts
   • If not specified, the value of $cargoArtifacts will be used
   • If cargoArtifacts is not specified, an error will be raised
   • If the specified path is a directory which contains a file called target.tar.zst, then that file will be used as specified below
   • If the specified path is a file (and not a directory) it is assumed that it contains a zstd compressed tarball and will be decompressed and unpacked into the specified cargo artifacts directory
   • If the specified path is a directory which contains another directory called target, then that directory will be used as specified below
   • If the specified path is a directory, its contents will be copied into the specified cargo artifacts directory
   • The previously prepared artifacts are expected to be a zstd compressed tarball
2. the path to cargo's artifact directory, where the previously prepared artifacts should be unpacked
   • If not specified, the value of $CARGO_TARGET_DIR will be used
   • If CARGO_TARGET_DIR is not set, cargo's default target location (i.e. ./target) will be used.

Note that as an optimization, some dependency artifacts will be symlinked instead of (deeply) copied to $CARGO_TARGET_DIR. To disable this behavior set doNotLinkInheritedArtifacts, and all artifacts will be copied as plain, writable files.

Automatic behavior: if cargoArtifacts is set, then inheritCargoArtifacts "$cargoArtifacts" "$CARGO_TARGET_DIR" will be run as a post patch hook.

Required nativeBuildInputs: assumes zstd is available on the $PATH

craneLib.installCargoArtifactsHook

Defines compressAndInstallCargoArtifactsDir() which handles installing cargo's artifact directory to the derivation's output as a zstd compressed tarball. It takes two positional arguments:

1. the installation directory for the output.
   • An error will be raised if not specified
   • Cargo's artifact directory will be compressed as a reproducible tarball with zstd compression. It will be written to this directory and named target.tar.zstd
2. the path to cargo's artifact directory
   • An error will be raised if not specified

If $zstdCompressionExtraArgs is set, compressAndInstallCargoArtifactsDir() will pass its contents along to zstd when compressing artifacts.

Defines dedupAndInstallCargoArtifactsDir() which handles installing cargo's artifact directory to the derivation's output after deduplicating identical files against a directory of previously prepared cargo artifacts. It takes three positional arguments:

1. the installation directory for the output.
   • An error will be raised if not specified
   • If the specified path is a directory which exists then the current cargo artifacts will be compared with the contents of said directory. Any files whose contents and paths match will be symbolically linked together to reduce the size of the data stored in the Nix store.
2. the path to cargo's artifact directory
   • An error will be raised if not specified
3. a path to the previously prepared cargo artifacts
   • An error will be raised if not specified
   • /dev/null can be specified here if there is no previous directory to deduplicate against

Defines prepareAndInstallCargoArtifactsDir() which handles installing cargo's artifact directory to the derivation's output. It takes three positional arguments:

1. the installation directory for the output.
   • If not specified, the value of $out will be used
   • Cargo's artifact directory will be installed based on the installation mode selected below
2. the path to cargo's artifact directory
   • If not specified, the value of $CARGO_TARGET_DIR will be used
   • If CARGO_TARGET_DIR is not set, cargo's default target location (i.e. ./target) will be used.
3. the installation mode to apply
   • If specified, the value of $installCargoArtifactsMode will be used, otherwise, a default value of "use-zstd" will be used
   • If set to "use-symlink" then dedupAndInstallCargoArtifactsDir() will be used.
     • If $cargoArtifacts is defined and $cargoArtifacts/target is a valid directory, it will be used during file deduplication
   • If set to "use-zstd" then compressAndInstallCargoArtifactsDir() will be used.
   • Otherwise an error will be raised if the mode is not recognized

Automatic behavior: if doInstallCargoArtifacts is set to 1, then prepareAndInstallCargoArtifactsDir "$out" "$CARGO_TARGET_DIR" will be run as a post install hook.

Required nativeBuildInputs: assumes zstd is available on the $PATH

craneLib.installFromCargoBuildLogHook

Defines installFromCargoBuildLog() which will use a build log produced by cargo to find and install any binaries and libraries which have been built. It takes two positional arguments:

1. a path to where artifacts should be installed
   • If not specified, the value of $out will be used
   • Binaries will be installed in a bin subdirectory
   • Libraries will be installed in a lib subdirectory
     • Note that only library targets with the staticlib and cdylib crate-types will be installed. Library targets with the rlib crate-type will be ignored
2. a path to a JSON formatted build log written by cargo
   • If not specified, the value of $cargoBuildLog will be used
   • If cargoBuildLog is not set, an error will be raised
   • This log can be captured, for example, via cargo build --message-format json-render-diagnostics >cargo-build.json

Defines postBuildInstallFromCargoBuildLog() which will use a build log produced by cargo to find and install any binaries and libraries which have been built into a temporary location defined by $postBuildInstallFromCargoBuildLogOut

Automatic behavior: if doNotPostBuildInstallCargoBinaries is not set, then $postBuildInstallFromCargoBuildLogOut will be set to a temporary directory and postBuildInstallFromCargoBuildLog will be run as a post build hook.

Required nativeBuildInputs: assumes cargo is available on the $PATH

craneLib.removeReferencesToRustToolchainHook

Defines removeReferencesToRustToolchain() which handles removing all references to the Rust toolchain from the installed binaries, ensuring that the final binaries do not have a (false) runtime dependency on the toolchain (usually due to references in panic messages). The current toolchain is detected via rustc --print sysroot. It takes 1 positional argument:

1. the installation directory for the output.

• If not specified, the value of $out will be used.
• If out is not specified, an error will be raised.

Automatic behavior: if doNotRemoveReferencesToRustToolchain is not set, then removeReferencesToRustToolchain "$out" will be run as a post install hook.

Required nativeBuildInputs: assumes rustc is available on the $PATH

craneLib.removeReferencesToVendoredSourcesHook

Defines removeReferencesToVendoredSources() which handles removing all references to vendored sources from the installed binaries, which ensures that nix does not consider the binaries as having a (runtime) dependency on the sources themselves. It takes two positional arguments:

1. the installation directory for the output.
   • If not specified, the value of $out will be used
   • If out is not specified, an error will be raised
2. a path to the vendored sources
   • If not specified, the value of $cargoVendorDir will be used
   • If cargoVendorDir is not specified, an error will be raised
   • Note: it is expected that this directory has the exact structure as would be produced by craneLib.vendorCargoDeps

Any patched binaries on aarch64-darwin will be signed. You can disable this functionality by setting doNotSign.

Automatic behavior: if cargoVendorDir is set and doNotRemoveReferencesToVendorDir is not set, then removeReferencesToVendoredSources "$out" "$cargoVendorDir" will be run as a post install hook.

craneLib.replaceCargoLockHook

Defines replaceCargoLock() which handles replacing or inserting a specified Cargo.lock file in the current directory. It takes one positional argument:

1. a file which will be copied to Cargo.lock in the current directory
   • If not specified, the value of $cargoLock will be used
   • If $cargoLock is not set, an error will be raised

Automatic behavior: if cargoLock is set and doNotReplaceCargoLock is not set, then replaceCargoLock "$cargoLock" will be run as a pre patch hook.