diff --git a/pkgs/xo-expression2.nix b/pkgs/xo-expression2.nix
index a821464d..c5064aeb 100644
--- a/pkgs/xo-expression2.nix
+++ b/pkgs/xo-expression2.nix
@@ -17,7 +17,7 @@
   doCheck ? true
 } :
 
-stdenv.mmkDerivation (finalattrs :
+stdenv.mkDerivation (finalattrs :
   {
     name = "xo-expression2";