diff --git a/mkClojureLib.nix b/mkClojureLib.nix
index 18e4bc3..b31ec6a 100644
--- a/mkClojureLib.nix
+++ b/mkClojureLib.nix
@@ -39,7 +39,7 @@ in stdenv.mkDerivation {
     clojure \
       -Scp     .:${build-tools-jar}:${classpath} \
       -Sdeps   ${build-tools-deps} \
-      -X:build \
+      -T:build \
       lib-uberjar \
       :project ${group}/${name} \
       :version ${version} \