before deadnix

modules/fonts.nix

@@ -1,13 +1,13 @@
 { pkgs, ... }:
 let
-  # Fetch the JSON file
+  # Fetch the JSON file and read its content
   fontsJson = builtins.fetchurl {
     url = "https://raw.githubusercontent.com/NixOS/nixpkgs/nixos-unstable/pkgs/data/fonts/nerd-fonts/manifests/fonts.json";
     sha256 = "1kdmk4ayckixxckxbik9jg4fdqqgm7s5x1lvzd95v1g09bhn33wg";
   };
 
   # Parse the JSON and extract package names
-  fonts = builtins.fromJSON fontsJson;
+  fonts = builtins.fromJSON (builtins.readFile fontsJson);
   packageNames = map (font: font.package) fonts;
 in
 {
@@ -18,5 +18,5 @@ in
       comic-mono
       nerdfonts
     ]
-    ++ packageNames;
+    ++ builtins.filter lib.attrsets.isDerivation (builtins.attrValues pkgs.nerd-fonts);
 }