rust-binary-template/flake.nix

{
  description = "A flake for building ${REPO_NAME}.";

  inputs = {
    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";

    flake-utils.url = "github:numtide/flake-utils";

    treefmt-nix.url = "github:numtide/treefmt-nix";
    treefmt-nix.inputs.nixpkgs.follows = "nixpkgs";
  };

  outputs = { self, nixpkgs, flake-utils, treefmt-nix, ... }@inputs:
    (flake-utils.lib.eachSystem
      (with flake-utils.lib.system; [ x86_64-linux aarch64-darwin ])
      (system: { checks.builds = self.packages.$${system}.default; })
      // flake-utils.lib.eachDefaultSystem (system:
        let
          pkgs = nixpkgs.legacyPackages.$${system};

          cargoToml = builtins.fromTOML (builtins.readFile ./Cargo.toml);

          treefmtEval = treefmt-nix.lib.evalModule pkgs (pkgs: {
            projectRootFile = "flake.nix";
            programs.rustfmt.enable = true;
            programs.nixfmt.enable = true;
          });
        in {
          packages.default = pkgs.rustPlatform.buildRustPackage {
            inherit (cargoToml.package) name version;
            src = ./.;
            cargoLock.lockFile = ./Cargo.lock;
          };

          formatter = treefmtEval.config.build.wrapper;
        }));
}