rec {
  description = "C++ Brainfuck Interpreter";

  inputs = {
    nixpkgs.url = "nixpkgs"; # Use nixpkgs from system registry
    flake-utils.url = "github:numtide/flake-utils";

    rust-overlay.url = "github:oxalica/rust-overlay";
    rust-overlay.inputs.nixpkgs.follows = "nixpkgs";
  };

  outputs = {
    self,
    nixpkgs,
    flake-utils,
    rust-overlay,
  }:
  # Create a shell (and possibly package) for each possible system, not only x86_64-linux
    flake-utils.lib.eachDefaultSystem (system: let
      pkgs = import nixpkgs {
        inherit system;
        config.allowUnfree = true;
        overlays = [
          rust-overlay.overlays.default
        ];
      };

      inherit (pkgs) lib stdenv;

      python = pkgs.python313.withPackages (p:
        with p; [
          pyside6
          ffmpeg-python
          matplotlib
          numpy
        ]);

      rust = pkgs.rust-bin.stable.latest.default.override {
        extensions = ["rust-src"]; # Include the Rust stdlib source (for IntelliJ)
      };

      # 64 bit C/C++ compilers that don't collide (use the same libc)
      bintools = pkgs.wrapBintoolsWith {
        bintools = pkgs.bintools.bintools; # Unwrapped bintools
        libc = pkgs.glibc;
      };
      gcc = pkgs.hiPrio (pkgs.wrapCCWith {
        cc = pkgs.gcc.cc; # Unwrapped gcc
        libc = pkgs.glibc;
        bintools = bintools;
      });
      clang = pkgs.wrapCCWith {
        cc = pkgs.clang.cc; # Unwrapped clang
        libc = pkgs.glibc;
        bintools = bintools;
      };

      # Multilib C/C++ compilers that don't collide (use the same libc)
      bintools_multilib = pkgs.wrapBintoolsWith {
        bintools = pkgs.bintools.bintools; # Unwrapped bintools
        libc = pkgs.glibc_multi;
      };
      gcc_multilib = pkgs.hiPrio (pkgs.wrapCCWith {
        cc = pkgs.gcc.cc; # Unwrapped gcc
        libc = pkgs.glibc_multi;
        bintools = bintools_multilib;
      });
      clang_multilib = pkgs.wrapCCWith {
        cc = pkgs.clang.cc; # Unwrapped clang
        libc = pkgs.glibc_multi;
        bintools = bintools_multilib;
      };

      # Stuff ran at build-time (e.g. cmake, autoPatchelfHook).
      # Architecture will be the build/target platform (relevant for e.g. cross-compilation).
      # Packages will be added to $PATH.
      nativeBuildInputs = with pkgs; [];

      # Stuff that's linked against.
      # Architecture will be the host platform.
      # Packages will be added to $PATH unless "strictDeps = true;".
      buildInputs = with pkgs; [
        # Languages:
        # python
        # rust
        bintools
        gcc
        clang
        # bintools_multilib
        # gcc_multilib
        # clang_multilib

        # C/C++:
        gdb
        valgrind
        gnumake
        cmake
        # boost
        # sfml

        # Qt:
        # qt6.qtbase
        # qt6.full
        # qt6.wrapQtAppsHook # For the shellHook
      ];
    in {
      # TODO: Add default packages for different languages
      # TODO: check nixpkgs docs for buildPythonApplication
      # packages.${system}.default = pkgs.buildPythonApplication {
      #   pname = "pyside6_image_viewer";
      #   version = "0.1.0";
      # };

      packages.${system}.default = stdenv.mkDerivation {
        pname = "bfuck";
        version = "1.0.0";
        src = ./.;
        inherit nativeBuildInputs buildInputs;
      };

      devShell = pkgs.mkShell {
        name = description;

        # Comments on buildInputs, nativeBuildInputs, buildPackages:
        # https://discourse.nixos.org/t/use-buildinputs-or-nativebuildinputs-for-nix-shell/8464
        # For our "nix develop" shell, buildInputs can be used for everything.

        inherit nativeBuildInputs buildInputs;

        # Rust stdlib source:
        # RUST_SRC_PATH = "${rust}/lib/rustlib/src/rust/library";

        # Custom dynamic libraries:
        # LD_LIBRARY_PATH = builtins.concatStringsSep ":" [
        #   # Rust Bevy GUI app
        #   "${pkgs.xorg.libX11}/lib"
        #   "${pkgs.xorg.libXcursor}/lib"
        #   "${pkgs.xorg.libXrandr}/lib"
        #   "${pkgs.xorg.libXi}/lib"
        #   "${pkgs.libGL}/lib"
        # ];

        # Dynamic libraries from buildinputs:
        # LD_LIBRARY_PATH = nixpkgs.lib.makeLibraryPath buildInputs;

        # Setup the shell when entering the "nix develop" environment (bash script).
        shellHook = let
          mkCmakeScript = type: let
            typeLower = lib.toLower type;
          in
            pkgs.writers.writeFish "cmake-${typeLower}.fish" ''
              cd $FLAKE_PROJECT_ROOT

              echo "Removing build directory ./cmake-build-${typeLower}/"
              rm -rf ./cmake-build-${typeLower}

              echo "Creating build directory"
              mkdir cmake-build-${typeLower}
              cd cmake-build-${typeLower}

              echo "Running cmake"
              cmake -G "Unix Makefiles" -DCMAKE_BUILD_TYPE="${type}" -DCMAKE_EXPORT_COMPILE_COMMANDS="On" ..

              echo "Linking compile_commands.json"
              cd ..
              ln -sf ./cmake-build-${typeLower}/compile_commands.json ./compile_commands.json
            '';

          cmakeDebug = mkCmakeScript "Debug";
          cmakeRelease = mkCmakeScript "Release";

          mkBuildScript = type: let
            typeLower = lib.toLower type;
          in
            pkgs.writers.writeFish "cmake-build.fish" ''
              cd $FLAKE_PROJECT_ROOT/cmake-build-${typeLower}

              echo "Running cmake"
              cmake --build .
            '';

          buildDebug = mkBuildScript "Debug";
          buildRelease = mkBuildScript "Release";

          # Use this to specify commands that should be ran after entering fish shell
          initProjectShell = pkgs.writers.writeFish "init-shell.fish" ''
            echo "Entering \"${description}\" environment..."

            # Determine the project root, used e.g. in cmake scripts
            set -g -x FLAKE_PROJECT_ROOT (git rev-parse --show-toplevel)

            # Add shell abbreviations specific to this build environment

            # Rust Bevy:
            # abbr -a build-release-windows "CARGO_FEATURE_PURE=1 cargo xwin build --release --target x86_64-pc-windows-msvc"

            # C/C++:
            abbr -a cmake-debug "${cmakeDebug}"
            abbr -a cmake-release "${cmakeRelease}"
            abbr -a build-debug "${buildDebug}"
            abbr -a build-release "${buildRelease}"
          '';
        in
          builtins.concatStringsSep "\n" [
            # Launch into pure fish shell
            ''
              exec "$(type -p fish)" -C "source ${initProjectShell} && abbr -a menu '${pkgs.bat}/bin/bat "${initProjectShell}"'"
            ''

            # Qt: Launch into wrapped fish shell
            # ''
            #   fishdir=$(mktemp -d)
            #   makeWrapper "$(type -p fish)" "$fishdir/fish" "''${qtWrapperArgs[@]}"
            #   exec "$fishdir/fish" -C "source ${initProjectShell} && abbr -a menu '${pkgs.bat}/bin/bat "${initProjectShell}"'"
            # ''
          ];
      };
    });
}