diff --git a/default.nix b/default.nix
index e13afcdb3..fb41a1297 100644
--- a/default.nix
+++ b/default.nix
@@ -1,10 +1,18 @@
 { pkgs ? import <nixpkgs> { } }:
 let
   src = import ./source.nix;
+  phase1 = pkgs.mastodon.override {
+    pname = "mastodon-queer-af";
+    version = "main";
+    srcOverride = src;
+    dependenciesDir = src;
+  };
 in
-pkgs.mastodon.override {
-  pname = "mastodon-queer-af";
-  version = "main";
-  srcOverride = src;
-  dependenciesDir = src;
-}
+  phase1.overrideAttrs (prev: {
+    mastodon-modules = phase1.mastodon-modules.overrideAttrs (prev: {
+      yarnOfflineCache = pkgs.fetchYarnDeps {
+        yarnLock = "${src}/yarn.lock";
+        sha256 = "0v47h3a0cw5fhffp0bajazd3731zkzqvn0vh4klpd4a29mf26y6n";
+      };
+    });
+  })