{
  description = "A CLI to display information about x509 certificates.";

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

    fenix = {
      url = "github:nix-community/fenix";
      inputs.nixpkgs.follows = "nixpkgs";
    };

    naersk = {
      url = "github:nix-community/naersk";
      inputs.nixpkgs.follows = "nixpkgs";
    };

    nix = {
      url = "github:nixos/nix/2.13.2";
    };

    flake-compat = { url = "github:edolstra/flake-compat"; flake = false; };
  };

  outputs =
    { self
    , nixpkgs
    , fenix
    , naersk
    , nix
    , ...
    } @ inputs:
    let
      supportedSystems = [ "x86_64-linux" "x86_64-darwin" "aarch64-darwin" ];

      forAllSystems = f: nixpkgs.lib.genAttrs supportedSystems (system: (forSystem system f));

      forSystem = system: f: f rec {
        inherit system;
        pkgs = import nixpkgs { inherit system; overlays = [ self.overlays.default ]; };
        lib = pkgs.lib;
      };

      fenixToolchain = system: with fenix.packages.${system};
        combine ([
          stable.clippy
          stable.rustc
          stable.cargo
          stable.rustfmt
          stable.rust-src
        ] ++ nixpkgs.lib.optionals (system == "x86_64-linux") [
          targets.x86_64-unknown-linux-musl.stable.rust-std
        ]);
    in
    {
      overlays.default = final: prev:
        let
          toolchain = fenixToolchain final.stdenv.system;
          naerskLib = final.callPackage naersk {
            cargo = toolchain;
            rustc = toolchain;
          };
          sharedAttrs = {
            pname = "x509-info";
            version = "0.1.0";
            src = builtins.path {
              name = "x509-info";
              path = self;
            };

            nativeBuildInputs = with final; [ ];
            buildInputs = with final; [ ] ++ lib.optionals (final.stdenv.isDarwin) (with final.darwin.apple_sdk.frameworks; [
              SystemConfiguration
            ]);

            copyBins = true;
            copyDocsToSeparateOutput = true;

            doCheck = true;
            doDoc = true;
            doDocFail = true;
            cargoTestOptions = f: f ++ [ "--all" ];

            override = { preBuild ? "", ... }: {
              preBuild = preBuild + ''
                # logRun "cargo clippy --all-targets --all-features -- -D warnings"
              '';
            };
          };
        in
        rec {
          x509-info = naerskLib.buildPackage sharedAttrs;
        } // nixpkgs.lib.optionalAttrs (prev.stdenv.system == "x86_64-linux") rec {
          default = x509-info-static;
          x509-info-static = naerskLib.buildPackage
            (sharedAttrs // {
              CARGO_BUILD_TARGET = "x86_64-unknown-linux-musl";
            });
        };

      devShells = forAllSystems ({ system, pkgs, ... }:
        let
          toolchain = fenixToolchain system;
          check = import ./nix/check.nix { inherit pkgs toolchain; };
        in
        {
          default = pkgs.mkShell {
            name = "x509-info-shell";

            RUST_SRC_PATH = "${toolchain}/lib/rustlib/src/rust/library";

            nativeBuildInputs = with pkgs; [ ];
            buildInputs = with pkgs; [
              toolchain
              rust-analyzer
              cargo-outdated
              cacert
              cargo-audit
              nixpkgs-fmt
              check.check-rustfmt
              check.check-spelling
              check.check-nixpkgs-fmt
              check.check-semver
            ]
            ++ lib.optionals (pkgs.stdenv.isDarwin) (with pkgs; [
              libiconv
              darwin.apple_sdk.frameworks.Security
            ])
            ++ lib.optionals (pkgs.stdenv.isLinux) (with pkgs; [
              checkpolicy
            ]);
          };
        });

      checks = forAllSystems ({ system, pkgs, ... }:
        let
          toolchain = fenixToolchain system;
          check = import ./nix/check.nix { inherit pkgs toolchain; };
        in
        {
          check-rustfmt = pkgs.runCommand "check-rustfmt" { buildInputs = [ check.check-rustfmt ]; } ''
            cd ${./.}
            check-rustfmt
            touch $out
          '';
          check-spelling = pkgs.runCommand "check-spelling" { buildInputs = [ check.check-spelling ]; } ''
            cd ${./.}
            check-spelling
            touch $out
          '';
          check-nixpkgs-fmt = pkgs.runCommand "check-nixpkgs-fmt" { buildInputs = [ check.check-nixpkgs-fmt ]; } ''
            cd ${./.}
            check-nixpkgs-fmt
            touch $out
          '';
        });

      packages = forAllSystems ({ system, pkgs, ... }:
        {
          inherit (pkgs) x509-info;
        } // nixpkgs.lib.optionalAttrs (system == "x86_64-linux") {
          inherit (pkgs) x509-info-static;
          default = pkgs.x509-info-static;
        } // nixpkgs.lib.optionalAttrs (pkgs.stdenv.isDarwin) {
          default = pkgs.x509-info;
        });
    };
}