{
  description = "A simple Go package";

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

  outputs = { self, nixpkgs }:
    let

      # System types to support.
      supportedSystems = [ "x86_64-linux" "x86_64-darwin" "aarch64-linux" "aarch64-darwin" ];

      # Helper function to generate an attrset '{ x86_64-linux = f "x86_64-linux"; ... }'.
      forAllSystems = nixpkgs.lib.genAttrs supportedSystems;

      # Nixpkgs instantiated for supported system types.
      nixpkgsFor = forAllSystems (system: import nixpkgs { inherit system; });

    in
    {

      # Requires dirty nixbld with access to docker daemon
      packages = forAllSystems (system:
        let
          pkgs = nixpkgsFor.${system};
          getImageWithSkopeo =
          let
          fixName = name: builtins.replaceStrings [ "/" ":" ] [ "-" "-" ] name;
          in
          { imageName
          , transport
            # To find the digest of an image, you can use skopeo:
            # see doc/functions.xml
          , imageDigest
          , sha256
          , os ? "linux"
          , # Image architecture, defaults to the architecture of the `hostPlatform` when unset
            arch ? pkgs.go.GOARCH
            # This is used to set name to the pulled image
          , finalImageName ? imageName
            # This used to set a tag to the pulled image
          , finalImageTag ? "latest"
            # This is used to disable TLS certificate verification, allowing access to http registries on (hopefully) trusted networks
          , tlsVerify ? true

          , name ? fixName "image-${finalImageName}-${finalImageTag}.tar"
          }:
                pkgs.runCommand name
            {
              inherit imageDigest;
              imageName = finalImageName;
              imageTag = finalImageTag;
              impureEnvVars = pkgs.lib.fetchers.proxyImpureEnvVars;
              outputHashMode = "flat";
              outputHashAlgo = "sha256";
              outputHash = sha256;

              nativeBuildInputs = [ pkgs.skopeo ];
              SSL_CERT_FILE = "${pkgs.cacert.out}/etc/ssl/certs/ca-bundle.crt";

              sourceURL = if transport == "docker-daemon:" then "${transport}${imageDigest}" else "${transport}${imageName}@${imageDigest}";
              destNameTag = "${finalImageName}:${finalImageTag}";
            } ''
            skopeo \
              --insecure-policy \
              --tmpdir=$TMPDIR \
              --override-os ${os} \
              --override-arch ${arch} \
              copy \
              --src-tls-verify=${pkgs.lib.boolToString tlsVerify} \
              "$sourceURL" "docker-archive://$out:$destNameTag" \
              | cat  # pipe through cat to force-disable progress bar
          '';
          pnsh = getImageWithSkopeo {
            transport   = "docker-daemon:";
            imageName   = "";
            imageDigest = "";
            sha256      = "";
          };

          # from: https://github.com/nix-community/home-manager/blob/70824bb5c790b820b189f62f643f795b1d2ade2e/modules/programs/neovim.nix#L412
          neovimConfig = pkgs.neovimUtils.makeNeovimConfig {
            viAlias = true;
            vimAlias = true;
            withPython3 = false;
            withRuby = false;
            withNodeJs = false;
            extraPython3Packages = _: [];
            extraLuaPackages = _: [];

            plugins = with pkgs.vimPlugins; [
              # highlighting
              nvim-treesitter.withAllGrammars
              playground
              gruvbox-material
              kanagawa-nvim
              lsp_lines-nvim
              gitsigns-nvim
              vim-helm
              lualine-nvim

              # external
              oil-nvim
              vim-fugitive
              venn-nvim
              gv-vim
              zoxide-vim
              obsidian-nvim
              go-nvim

              # Coding
              fzf-lua
              nvim-lspconfig
              null-ls-nvim
              lsp_signature-nvim
              nvim-dap
              nvim-dap-ui
              nvim-nio
              nvim-dap-python
              luasnip
              vim-test
              nvim-lint
              vim-surround
              conform-nvim
              trouble-nvim
              vim-easy-align
              nvim-comment

              # cmp
              nvim-cmp
              cmp-cmdline
              cmp-nvim-lsp
              cmp-buffer
              cmp-path
              cmp_luasnip

              # conjure
              vim-racket
              nvim-parinfer
              hotpot-nvim
            ];
            customRC = "";
          };

          neovim-package = pkgs.wrapNeovimUnstable pkgs.neovim-unwrapped (neovimConfig
            // {
              wrapRc = false;
            });
        in
        {
          pnsh-container = pnsh;
          neovim-container = pkgs.dockerTools.buildImage {
            name =  "";
            fromImage = pnsh;
            copyToRoot = pkgs.buildEnv {
              extraPrefix = "/usr";
              name = "neovim-nix-ide-usr";
              paths =  with pkgs; [
                neovim-package
                docker-client
                zoxide
              ];
            };
            config = {
              Entrypoint = ["/bin/zsh"];
              Cmd = ["-c" "boot"];
            };
          };
        });

      # The default package for 'nix build'. This makes sense if the
      # flake provides only one package or there is a clear "main"
      # package.
      defaultPackage = forAllSystems (system: self.packages.${system}.neovim-container);
    };
}