diff --git a/flake.nix b/flake.nix
index 6240e10..6d2d5b9 100644
--- a/flake.nix
+++ b/flake.nix
@@ -9,7 +9,7 @@
       system:
         let
 	  pkgs = import nixpkgs { inherit system; };
-	  katex-server = pkgs.callPackage ./default.nix {};
+	  katex-server = import ./default.nix { inherit (pkgs) mkYarnPackage; };
 	in
           {
             packages = { inherit katex-server; };