diff --git a/DDC/Core/Transform/Boxing.hs b/DDC/Core/Transform/Boxing.hs
--- a/DDC/Core/Transform/Boxing.hs
+++ b/DDC/Core/Transform/Boxing.hs
@@ -213,7 +213,7 @@
 -- | Manage boxing in the type of an imported value.
 boxingImportValue 
         :: Config a n
-        => (n, ImportSource n)
+        -> (n, ImportSource n)
         -> (n, ImportSource n)
 
 boxingImportValue config (n, isrc)
diff --git a/ddc-core-simpl.cabal b/ddc-core-simpl.cabal
--- a/ddc-core-simpl.cabal
+++ b/ddc-core-simpl.cabal
@@ -1,5 +1,5 @@
 Name:           ddc-core-simpl
-Version:        0.4.1.1
+Version:        0.4.1.2
 License:        MIT
 License-file:   LICENSE
 Author:         The Disciplined Disciple Compiler Strike Force