template-nix-rust/flake.nix

{
  inputs = {
    advisory-db = {
      url = "github:rustsec/advisory-db";
      flake = false;
    };
    crane.url = "github:ipetkov/crane";
    flake-utils.url = "github:numtide/flake-utils";
    nix-filter.url = "github:numtide/nix-filter";
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-24.05";
    rust-overlay.url = "github:oxalica/rust-overlay";
    treefmt-nix.url = "github:numtide/treefmt-nix";
  };

  outputs =
    {
      self,
      advisory-db,
      crane,
      flake-utils,
      nix-filter,
      nixpkgs,
      rust-overlay,
      treefmt-nix,
    }:
    flake-utils.lib.eachDefaultSystem (
      system:
      let
        overlays = [
          (import rust-overlay)
          (final: prev: {
            nix-filter = nix-filter.lib;
            rust-toolchain = pkgs.rust-bin.stable.latest.default;
            rust-dev-toolchain = pkgs.rust-toolchain.override {
              extensions = [
                "rust-analyzer"
                "rust-src"
              ];
            };
          })
        ];

        pkgs = import nixpkgs { inherit overlays system; };
        craneLib = (crane.mkLib pkgs).overrideToolchain pkgs.rust-toolchain;
        stdenv = pkgs.stdenvAdapters.useMoldLinker pkgs.stdenv;

        nativeBuildInputs = with pkgs; [
          clang_18
          mold
        ];

        sourceAndFixtures = path: type: (craneLib.filterCargoSources path type);
        src = pkgs.lib.cleanSourceWith {
          src = ./.;
          filter = sourceAndFixtures;
        };

        commonArgs = {
          inherit src stdenv nativeBuildInputs;
          strictDeps = true;
          LIBCLANG_PATH = "${pkgs.llvmPackages.libclang.lib}/lib";
        };

        cargoArtifacts = craneLib.buildDepsOnly commonArgs;

        treefmtEval = treefmt-nix.lib.evalModule pkgs {
          projectRootFile = "flake.nix";
          programs = {
            nixfmt.enable = true;
            nixfmt.package = pkgs.nixfmt-rfc-style;
            shfmt.enable = true;
            rustfmt.enable = true;
          };
          settings.formatter.rustfmt.command = pkgs.lib.mkForce "${pkgs.rust-toolchain}/bin/rustfmt";
        };

        my-project = craneLib.buildPackage (commonArgs // { inherit cargoArtifacts; });
      in
      rec {
        # `nix build`
        packages.default = my-project;

        # Tests
        checks = {
          clippy = craneLib.cargoClippy (
            commonArgs
            // {
              inherit cargoArtifacts;
              cargoClippyExtraArgs = "--all-targets -- --deny warnings";
            }
          );

          fmt = craneLib.cargoFmt (commonArgs // { inherit src; });

          audit = craneLib.cargoAudit (commonArgs // { inherit src advisory-db; });

          nextest = craneLib.cargoNextest (
            commonArgs
            // {
              inherit cargoArtifacts;
              partitions = 1;
              partitionType = "count";
            }
          );
        };

        # For `nix fmt`
        formatter = treefmtEval.config.build.wrapper;

        # `nix develop`
        devShells.default = pkgs.mkShell {
          inherit nativeBuildInputs;
          buildInputs = with pkgs; [
            bacon
            cargo-edit
            cargo-features-manager
            cargo-machete
            cargo-nextest
            cargo-watch
            hyperfine
            just
            rust-dev-toolchain
            watchexec
          ];
          shellHook = ''
            export RUST_SRC_PATH=${pkgs.rustPlatform.rustLibSrc} # Required for rust-analyzer
            echo
            echo "✨ Welcome to the My Project development environment! ✨"
            echo "Run 'just' to see available commands."
            echo
          '';
        };

      }
    );
}