home: put modules into folders

home/comma/default.nix

@@ -0,0 +1,29 @@
+{ config, lib, pkgs, ... }:
+let
+  cfg = config.my.home.comma;
+in
+{
+  options.my.home.comma = with lib; {
+    enable = my.mkDisableOption "comma configuration";
+
+    pkgsFlake = mkOption {
+      type = types.str;
+      default = "pkgs";
+      example = "nixpkgs";
+      description = ''
+        Which flake from the registry should be used with
+        <command>nix shell</command>.
+      '';
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    home.packages = with pkgs; [
+      ambroisie.comma
+    ];
+
+    home.sessionVariables = {
+      COMMA_PKGS_FLAKE = cfg.pkgsFlake;
+    };
+  };
+}