diff --git a/src/Type/Data/Num/Decimal/Digit.hs b/src/Type/Data/Num/Decimal/Digit.hs
--- a/src/Type/Data/Num/Decimal/Digit.hs
+++ b/src/Type/Data/Num/Decimal/Digit.hs
@@ -45,7 +45,6 @@
 
 class C d => Pos d where
     switchPos ::
-        (Pos d) =>
         f Dec1 ->
         f Dec2 ->
         f Dec3 ->
diff --git a/tfp.cabal b/tfp.cabal
--- a/tfp.cabal
+++ b/tfp.cabal
@@ -1,5 +1,5 @@
 name:           tfp
-version:        1.0
+version:        1.0.0.1
 build-type:     Simple
 license:        BSD3
 license-file:   LICENSE
@@ -17,19 +17,19 @@
   which provides an intuitive way to parameterize data types
   and functions on numerical values at compile time.
 category:       Type System
-tested-with:    GHC == 7.4.2, GHC == 7.6.3, GHC == 7.8.1
+tested-with:    GHC == 7.4.2, GHC == 7.6.3, GHC == 7.8.4, GHC == 8.0.1
 cabal-version:  >= 1.14
 extra-source-files:
   CHANGES
 
 source-repository head
   type:         darcs
-  location:     http://code.haskell.org/~thielema/tfp/
+  location:     http://hub.darcs.net/thielema/tfp/
 
 source-repository this
-  tag:          1.0
+  tag:          1.0.0.1
   type:         darcs
-  location:     http://code.haskell.org/~thielema/tfp/
+  location:     http://hub.darcs.net/thielema/tfp/
 
 
 library {
@@ -38,6 +38,8 @@
     utility-ht >=0.0.10 && <0.1,
     base >=3.0 && <5
   ghc-options: -Wall
+  if impl(ghc>=8.0)
+    ghc-options: -fno-warn-redundant-constraints
   hs-source-dirs: src
   exposed-modules:
     Data.SizedInt