diff --git a/sv2v.cabal b/sv2v.cabal
index 65d9eb4..e0f8d24 100644
--- a/sv2v.cabal
+++ b/sv2v.cabal
@@ -73,6 +73,7 @@ executable sv2v
     -with-rtsopts=-N
     -funbox-strict-fields
     -Wall
+    -j
 
 source-repository head
   type:     git