let's try this

.forgejo/install-emacs/flake.nix

@@ -0,0 +1,21 @@
+{
+  description = "Setup Emacs Action";
+
+  inputs =
+    {
+      nixpkgs.url = "nixpkgs/nixpkgs-unstable";
+      flake-utils.url = "github:numtide/flake-utils";
+    };
+
+  outputs = { self, nixpkgs, flake-utils }:
+    flake-utils.lib.eachDefaultSystem (system:
+      let
+        pkgs = import nixpkgs { inherit system; };
+      in
+      {
+        devShell = pkgs.mkShell {
+          buildInputs = with pkgs; [ pkgs.shellcheck ];
+        };
+      }
+    );
+}