diff --git a/Data/Repa/Eval/Elt.hs b/Data/Repa/Eval/Elt.hs
--- a/Data/Repa/Eval/Elt.hs
+++ b/Data/Repa/Eval/Elt.hs
@@ -3,9 +3,8 @@
 module Data.Repa.Eval.Elt
         (Elt (..))
 where
-import GHC.Prim
 import GHC.Exts
-import GHC.Types
+import GHC.IO (IO(IO))
 import GHC.Word
 import GHC.Int
 import GHC.Generics
@@ -142,7 +141,7 @@
 
 -- Floating -------------------------------------------------------------------
 instance Elt Float where
- touch (F# f)
+ touch f
   = IO (\state -> case touch# f state of
                         state' -> (# state', () #))
  {-# INLINE touch #-}
@@ -155,7 +154,7 @@
 
 
 instance Elt Double where
- touch (D# d)
+ touch d
   = IO (\state -> case touch# d state of
                         state' -> (# state', () #))
  {-# INLINE touch #-}
@@ -169,7 +168,7 @@
 
 -- Int ------------------------------------------------------------------------
 instance Elt Int where
- touch (I# i)
+ touch i
   = IO (\state -> case touch# i state of
                         state' -> (# state', () #))
  {-# INLINE touch #-}
@@ -182,7 +181,7 @@
 
 
 instance Elt Int8 where
- touch (I8# w)
+ touch w
   = IO (\state -> case touch# w state of
                         state' -> (# state', () #))
  {-# INLINE touch #-}
@@ -195,7 +194,7 @@
 
 
 instance Elt Int16 where
- touch (I16# w)
+ touch w
   = IO (\state -> case touch# w state of
                         state' -> (# state', () #))
  {-# INLINE touch #-}
@@ -208,7 +207,7 @@
 
 
 instance Elt Int32 where
- touch (I32# w)
+ touch w
   = IO (\state -> case touch# w state of
                         state' -> (# state', () #))
  {-# INLINE touch #-}
@@ -221,7 +220,7 @@
 
 
 instance Elt Int64 where
- touch (I64# w)
+ touch w
   = IO (\state -> case touch# w state of
                         state' -> (# state', () #))
  {-# INLINE touch #-}
@@ -235,7 +234,7 @@
 
 -- Word -----------------------------------------------------------------------
 instance Elt Word where
- touch (W# i)
+ touch i
   = IO (\state -> case touch# i state of
                         state' -> (# state', () #))
  {-# INLINE touch #-}
@@ -248,7 +247,7 @@
 
 
 instance Elt Word8 where
- touch (W8# w)
+ touch w
   = IO (\state -> case touch# w state of
                         state' -> (# state', () #))
  {-# INLINE touch #-}
@@ -261,7 +260,7 @@
 
 
 instance Elt Word16 where
- touch (W16# w)
+ touch w
   = IO (\state -> case touch# w state of
                         state' -> (# state', () #))
  {-# INLINE touch #-}
@@ -274,7 +273,7 @@
 
 
 instance Elt Word32 where
- touch (W32# w)
+ touch w
   = IO (\state -> case touch# w state of
                         state' -> (# state', () #))
  {-# INLINE touch #-}
@@ -287,7 +286,7 @@
 
 
 instance Elt Word64 where
- touch (W64# w)
+ touch w
   = IO (\state -> case touch# w state of
                         state' -> (# state', () #))
  {-# INLINE touch #-}
diff --git a/repa-eval.cabal b/repa-eval.cabal
--- a/repa-eval.cabal
+++ b/repa-eval.cabal
@@ -1,11 +1,11 @@
 Name:           repa-eval
-Version:        4.2.3.1
+Version:        4.2.4.0
 License:        BSD3
 License-file:   LICENSE
 Author:         The Repa Development Team
 Maintainer:     Ben Lippmeier <benl@ouroborus.net>
 Build-Type:     Simple
-Cabal-Version:  >=1.6
+Cabal-Version:  >=1.10
 Stability:      experimental
 Category:       Data Structures
 Homepage:       http://repa.ouroborus.net
@@ -19,14 +19,14 @@
 
 Library
   Build-Depends: 
-        base            == 4.9.*,
-        ghc-prim        == 0.5.*
-
+        base            >= 4.9 && <4.22
   Exposed-modules:
         Data.Repa.Eval.Elt
         Data.Repa.Eval.Gang
         Data.Repa.Eval.Generic.Seq
         Data.Repa.Eval.Generic.Par
+  
+  Default-Language: Haskell2010
 
   Other-modules:
         Data.Repa.Eval.Generic.Seq.Chunked
@@ -42,7 +42,7 @@
         -Wall -fno-warn-missing-signatures
         -O2
 
-  extensions:
+  default-extensions:
         NoMonomorphismRestriction
         BangPatterns
         MagicHash