{
  description = "A Nix-flake-based Rust development environment";
  nixConfig = {
    extra-substituters = [
      # "https://nixcache.vlt81.de"
      "https://llama-cpp.cachix.org"
      "https://cuda-maintainers.cachix.org"
    ];
    extra-trusted-public-keys = [
      # "nixcache.vlt81.de:nw0FfUpePtL6P3IMNT9X6oln0Wg9REZINtkkI9SisqQ="
      "llama-cpp.cachix.org-1:H75X+w83wUKTIPSO1KWy9ADUrzThyGs8P5tmAbkWhQc="
      "cuda-maintainers.cachix.org-1:0dq3bujKpuEPMCX6U4WylrUDZ9JyUG0VpVZa7CNfq5E="
    ];
  };
  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable-small";
    rust-overlay.url = "github:oxalica/rust-overlay";
    flake-utils.url = "github:numtide/flake-utils";
    flake-parts.url = "github:hercules-ci/flake-parts";
    devshell.url = "github:numtide/devshell";
    npmlock2nix = {
      url = "github:nix-community/npmlock2nix";
      flake = false;
    };
    llama-cpp = {
      url = "github:ggerganov/llama.cpp/b4604";
      inputs.nixpkgs.follows = "nixpkgs";
      inputs.flake-parts.follows = "flake-parts";
    };
  };

  outputs =
    { self
    , nixpkgs
    , rust-overlay
    , flake-utils
    , devshell
    , npmlock2nix
    , llama-cpp
    , ...
    }:
    flake-utils.lib.eachDefaultSystem
      (system:
      let
        overlays = [
          llama-cpp.overlays.default
          rust-overlay.overlays.default
          devshell.overlays.default
          (final: prev: {
            customRustToolchain = prev.rust-bin.fromRustupToolchainFile ./rust-toolchain.toml;
          })
          (final: prev: {
            nodejs-16_x = prev.nodePackages.nodejs; # needed for npmlock2nix
          })
          (final: prev: {
            npmlock2nix = import npmlock2nix { pkgs = prev; };
          })
          (final: prev: {
            prev.rocmPackages.clr = prev.rocmPackages.clr.overrideDerivation (oldAttrs: {
              passthru = {
                gpuTargets = rocmTargets;

                updateScript = oldAttrs.passthru.updateScript;

                impureTests = oldAttrs.passthru.impureTests;
              };
            });
          })
        ];
        pkgs = import nixpkgs {
          inherit system overlays;
          config = {
            allowUnfree = true;
            rocmSupport = true;
          };
        };
        customNodeModules = pkgs.npmlock2nix.v2.node_modules {
          src = ./.;
          nodejs = pkgs.nodejs_22;
        };
        buildInputs = with pkgs; [
          harfbuzz
          openssl
          pango
          sqlite
          mariadb
          zlib
          clang
          libclang
          gzip
          coreutils
          gdb
          glib
          glibc
          wayland-utils
          waylandpp
          kdePackages.wayland
          libxkbcommon
          webkitgtk_4_1
          libsoup_3
          gtk3
          libGL
          wayland
        ];
        rocmTargets = [
          "gfx1100"
          "gfx1102"
          "gfx1103"
        ];
      in
      {
        apps.devshell = self.outputs.devShells.${system}.default.flakeApp;
        packages = {
          cargo-leptos = pkgs.callPackage ./.nix/cargo-leptos.nix { };
          # llama-cpp = pkgs.callPackage "${llama-cpp}/.devops/nix/scope.nix" { };
          myllamacpp = with pkgs;
            llamaPackages.llama-cpp.overrideDerivation (oldAttrs: {
              # speeds up builts by only building for a needed rocmTargets...
              cmakeFlags = [
                (lib.cmakeBool "LLAMA_BUILD_SERVER" true)
                (lib.cmakeBool "BUILD_SHARED_LIBS" true)
                (lib.cmakeBool "CMAKE_SKIP_BUILD_RPATH" true)
                (lib.cmakeBool "LLAMA_CURL" true)
                (lib.cmakeBool "GGML_NATIVE" true)
                (lib.cmakeBool "GGML_BLAS" false)
                (lib.cmakeBool "GGML_CUDA" false)
                (lib.cmakeBool "GGML_HIP" true) # new one ? kinda undocumented ?
                (lib.cmakeBool "GGML_HIPBLAS" true) # seems to be depr
                (lib.cmakeBool "GGML_METAL" false)
                (lib.cmakeBool "GGML_VULKAN" false)
                (lib.cmakeBool "GGML_STATIC" false)
                (lib.cmakeBool "GGML_FMA" true)
                (lib.cmakeBool "GGML_F16C" true)
                (lib.cmakeBool "GGML_AVX2" true)
                (lib.cmakeBool "GGML_AVX512" false)
                (lib.cmakeFeature "CMAKE_HIP_COMPILER" "${rocmPackages.llvm.clang}/bin/clang")
                (lib.cmakeFeature "CMAKE_HIP_ARCHITECTURES" (builtins.concatStringsSep ";" rocmTargets))
                (lib.cmakeFeature "AMDGPU_TARGETS" (builtins.concatStringsSep ";" rocmTargets))
              ];
            });
        };
        devShells.default = pkgs.mkShell {
          packages = with pkgs;
            [
              # customNodeModules
              customRustToolchain
              # self.packages.${system}.myllamacpp
              # rustup
              bacon
              binaryen
              cacert
              trunk
              cargo-bloat
              cargo-docset
              cargo-machete
              cargo-limit
              cargo-deny
              cargo-edit
              cargo-watch
              cargo-make
              cargo-generate
              cargo-udeps
              self.packages.${system}.cargo-leptos
              # wasm-bindgen-cli
              wasm-bindgen-cli_0_2_100
              # (wasm-bindgen-cli.override {
              #   version = "0.2.93";
              #   hash = "sha256-DDdu5mM3gneraM85pAepBXWn3TMofarVR4NbjMdz3r0=";
              #   cargoHash = "sha256-birrg+XABBHHKJxfTKAMSlmTVYLmnmqMDfRnmG6g/YQ=";
              # })
              cargo-outdated
              cargo-release
              calc
              # jre8 # needed for xmlls
              dart-sass
              # trunk
              fish
              inotify-tools
              leptosfmt
              mold
              # nodejs_20
              pkg-config
              rustywind
              sccache
              sqlx-cli
              unzip
              rocmPackages.rocminfo
            ]
            ++ buildInputs;

          buildInputs = buildInputs;
          shellHook = ''
            # setup node-modules
            export NPM_LOCAL_PREFIX=${customNodeModules}/node_modules
            (ln -s $NPM_LOCAL_PREFIX ./node_modules 2>/dev/null || unlink ./node_modules) && ln -s $NPM_LOCAL_PREFIX ./node_modules 2>/dev/null

            # export NIX_LD_LIBRARY_PATH=${pkgs.lib.makeLibraryPath buildInputs}:$NIX_LD_LIBRARY_PATH
            export LD_LIBRARY_PATH="${pkgs.lib.makeLibraryPath buildInputs}"
            export LEPTOS_SASS_VERSION=1.71.0
            export LEPTOS_TAILWIND_VERSION=3.4.17
            export MALLOC_CONF=thp:always,metadata_thp:always
          '';
        };
      });
}