dotfiles/.config/nixpkgs/elvish/flake.nix

{
  description = "Elvish configuration";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
    flake-utils.url = "github:numtide/flake-utils";
  };

  outputs = { self, nixpkgs, flake-utils }:
    flake-utils.lib.eachDefaultSystem (system:
      with nixpkgs.legacyPackages.${system}; {
        packages.carapace-bin = buildGo121Module rec {
          pname = "carapace-bin";
          version = "0.27.0";

          src = fetchFromGitHub {
            owner = "rsteube";
            repo = "carapace-bin";
            rev = "v${version}";
            hash = "sha256-UcJbWOYkNUJEilJL/LG5o+I1ugqEOEGfs+uvKUMnTMU=";
          };

          ldflags = [ "-s" "-w" ];

          tags = [ "release" ];

          subPackages = [ "cmd/carapace" ];

          preBuild = ''
            go generate ./...
          '';

          vendorSha256 = "sha256-PN8ARsJQqRj333ervoy24PZoWkrCIYiGxOovzEhPNZQ=";
        };

        packages.elvish =
          let
            carapace-bin = self.packages.${system}.carapace-bin;
            config = runCommand "elvish-config" {
              nativeBuildInputs = [ makeWrapper ];
            } ''
              mkdir -p $out/elvish

              cp -r ${./lib} $out/elvish/lib

              cat <<EOF > $out/elvish/rc.elv
              use config
              eval (carapace _carapace|slurp)
              EOF
            '';
          in
          writeScriptBin "elvish" ''
            #!/bin/sh
            export XDG_DATA_DIRS="${config}:$XDG_DATA_DIRS"
            export PATH="${carapace-bin}/bin:$PATH"
            if command -v keyctl > /dev/null && [ -z "$KEYCTL_INIT" ]; then
              export KEYCTL_INIT=1
              keyctl new_session >/dev/null
            fi
            if [ -z "$XDG_RUNTIME_DIR" ] && [ -n "$TMPDIR" ]; then
              export XDG_RUNTIME_DIR="$TMPDIR"
            fi
            exec ${elvish}/bin/elvish -rc "${config}/elvish/rc.elv" "$@"
          '';

        packages.default = self.packages.${system}.elvish;
      }
    );
}