diff --git a/pkgs/fabric-server/default.nix b/pkgs/fabric-server/default.nix
index c2100ad..b4c81f0 100644
--- a/pkgs/fabric-server/default.nix
+++ b/pkgs/fabric-server/default.nix
@@ -1,7 +1,7 @@
 { callPackage, writeTextFile, writeShellScriptBin, minecraft-server, jre_headless }:
 
 let
-  loader = callPackage ./generate-loader.nix { };
+  loader = callPackage ./generate-loader.nix { lock = import ./lock.nix; };
   log4j = writeTextFile {
     name = "log4j.xml";
     text = ''
diff --git a/pkgs/fabric-server/generate-loader.nix b/pkgs/fabric-server/generate-loader.nix
index 252f9f7..e1daeab 100644
--- a/pkgs/fabric-server/generate-loader.nix
+++ b/pkgs/fabric-server/generate-loader.nix
@@ -1,7 +1,6 @@
-{ lib, fetchurl, stdenv, unzip, zip, jre_headless }:
+{ lib, fetchurl, stdenv, unzip, zip, jre_headless, lock }:
 
 let
-  lock = import ./lock.nix;
   libraries = lib.forEach lock.libraries fetchurl;
 in
 stdenv.mkDerivation {
@@ -23,7 +22,7 @@ stdenv.mkDerivation {
     EOF
 
     cat > fabric-server-launch.properties << EOF
-    launch.mainClass=net.fabricmc.loader.impl.launch.knot.KnotServer
+    launch.mainClass=${lock.mainClass}
     EOF
   '';