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

{
  description = "Elvish configuration";

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

  outputs = { self, nixpkgs }:
    {
      packages.x86_64-linux.carapace-bin =
        with import nixpkgs {
          system = "x86_64-linux";
        };
        buildGoModule rec {
          pname = "carapace-bin";
          version = "0.19.0";

          src = fetchFromGitHub {
            owner = "rsteube";
            repo = "carapace-bin";
            rev = "v${version}";
            sha256 = "sha256-Bdtuehfp81fq1ZSV+7jwSmxViu8FzVbBGoZ2HfDda5g=";
          };

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

          patches = [
            # https://github.com/rsteube/carapace-bin/pull/1480
            ./carapace-nix-build.patch
          ];

          tags = [ "release" ];

          subPackages = [ "cmd/carapace" ];

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

          vendorSha256 = "sha256-WXntyDbpGEXHkYgv21vN/JG/CVn6SqnMhmgXfFEQ9eM=";
        };

      packages.x86_64-linux.elvish =
        with import nixpkgs {
          system = "x86_64-linux";
        };
        let
          carapace-bin = self.packages.x86_64-linux.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:$PATH"
          if [ -z "$KEYCTL_INIT" ]; then
            export KEYCTL_INIT=1
            keyctl new_session >/dev/null
          fi
          exec ${elvish}/bin/elvish -rc "${config}/elvish/rc.elv" "$@"
        '';

      packages.x86_64-linux.default = self.packages.x86_64-linux.elvish;
    };
}