Use modules folder

modules/startpage/default.nix

@@ -0,0 +1,26 @@
+{ pkgs, lib, ... }:
+
+let
+  theme = import ../theme;
+  startpageDir = import ./dir.nix;
+  out = "${startpageDir}.tmp/";
+in
+{
+  home.file = {
+    "${out}" = {
+      source = ./html;
+      recursive = true;
+    };
+    "${out}colors.css".text = ":root {\n" + (theme.css lib) + "\n}";
+  };
+  # Make files not symlinks, this causes issues displaying in Firefox
+  home.activation.startpage = lib.hm.dag.entryAfter["writeBoundary"] ''
+    mkdir -p ${startpageDir}
+    mv ${out}* ${startpageDir}
+    rmdir ${out}
+    cd ${startpageDir}
+    for file in `find -type l`; do
+      cp --remove-destination `readlink $file` $file
+    done
+  '';
+}