diff --git a/plailude.cabal b/plailude.cabal
--- a/plailude.cabal
+++ b/plailude.cabal
@@ -1,5 +1,5 @@
 name:                plailude
-version:             0.2.1
+version:             0.2.2
 synopsis:            plaimi's prelude
 description:         The prelude used internally at plaimi.
 
@@ -30,7 +30,7 @@
                        Function
                        Function.Compose
   other-extensions:    GeneralizedNewtypeDeriving
-  build-depends:       base >=4.6 && <4.7,
+  build-depends:       base >=4.6 && <4.8,
                        bytestring >=0.10 && <0.11,
                        time >=1.4 && <1.5
   hs-source-dirs:      src
diff --git a/src/Data/Time/Units.hs b/src/Data/Time/Units.hs
--- a/src/Data/Time/Units.hs
+++ b/src/Data/Time/Units.hs
@@ -16,7 +16,7 @@
 class TimeUnit t where
   -- | Get out the value in a 'TimeUnit'. The value's type is
   -- polymorphic and constrained to 'Num'.
-  timeVal :: (TimeUnit t, Num n) => t -> n
+  timeVal :: Num n => t -> n
 
 instance TimeUnit Int where
   -- | The value of a 'TimeUnit' 'Int' is simply the 'Int' value.