diff --git a/Type/Digits.hs b/Type/Digits.hs
--- a/Type/Digits.hs
+++ b/Type/Digits.hs
@@ -43,7 +43,7 @@
 
 -- | Convert a number to the name of the corresponding digit -- error if the
 -- argument is out of range.
-digit :: Num a => a -> Name
+digit :: (Show a, Eq a, Num a) => a -> Name
 digit r = $(caseE [| r |] $ [
   match (litP (IntegerL k))
           (normalB $ liftNameG $ mkName n) []
@@ -78,7 +78,7 @@
 
 -- | Converts an @Integral@ to a type-level numeral using as many digits as it
 -- takes that particular number.
-flexible :: Integral a => a -> [Name]
+flexible :: (Show a, Eq a, Integral a) => a -> [Name]
 flexible
   | 0 == radix = digit' -- NB guard against @/0@ -- e.g. number of elements in @a@ = radix
   | otherwise = w where
@@ -90,7 +90,7 @@
 
 -- | Converts a @Bounded@ @Integral@ to a type-level numeral using exactly the
 -- number of digits it takes to represent each value of that type uniquely.
-fixed :: forall a. (Bounded a, Integral a) => a -> [Name]
+fixed :: forall a. (Bounded a, Show a, Eq a, Integral a) => a -> [Name]
 fixed = exactly (ceiling $ width [qProxy|a|]) . flexible
 
 
diff --git a/type-digits.cabal b/type-digits.cabal
--- a/type-digits.cabal
+++ b/type-digits.cabal
@@ -1,5 +1,5 @@
 Name:           type-digits
-Version:        0.1.0.1
+Version:        0.1.0.2
 License:        BSD3
 License-File:   LICENSE
 Author:         Nicolas Frisby <nicolas.frisby@gmail.com>