diff --git a/src/Data/Validity.hs b/src/Data/Validity.hs
--- a/src/Data/Validity.hs
+++ b/src/Data/Validity.hs
@@ -4,6 +4,9 @@
 {-# LANGUAGE FlexibleContexts #-}
 {-# LANGUAGE FlexibleInstances #-}
 {-# LANGUAGE TypeOperators #-}
+#if MIN_VERSION_base(4,9,0)
+{-# OPTIONS_GHC -fno-warn-redundant-constraints #-}
+#endif
 
 {-|
 
@@ -37,9 +40,9 @@
     -}
 module Data.Validity
     ( Validity(..)
-    , isValid
     -- * Helper functions to define 'validate'
     , trivialValidation
+    , genericValidate
     , check
     , declare
     , annotate
@@ -49,6 +52,7 @@
     , valid
     -- * Utilities
     -- ** Utilities for validity checking
+    , isValid
     , isInvalid
     , constructValid
     , constructValidUnsafe
@@ -70,22 +74,26 @@
 #if MIN_VERSION_base(4,9,0)
 import Data.List.NonEmpty (NonEmpty((:|)))
 #endif
-import Data.Maybe (Maybe, fromMaybe)
+import Data.Maybe (fromMaybe)
 #if MIN_VERSION_base(4,8,0)
 #else
 import Data.Monoid
 import Data.Ratio
 #endif
-import Data.Int (Int, Int16, Int32, Int64, Int8)
+import Data.Int (Int16, Int32, Int64, Int8)
+#if MIN_VERSION_base(4,8,0)
+import Data.Word (Word16, Word32, Word64, Word8)
+#else
 import Data.Word (Word, Word16, Word32, Word64, Word8)
+#endif
 import GHC.Generics
 #if MIN_VERSION_base(4,8,0)
-import GHC.Natural (Natural, isValidNatural)
+import GHC.Natural
 #endif
 import GHC.Real (Ratio(..))
 
 -- | A class of types that have additional invariants defined upon them
--- that aren't enforced by the type system
+
 --
 -- === Purpose
 --
@@ -112,7 +120,7 @@
 --
 -- === Semantics
 --
--- 'isValid' should be an underapproximation of actual validity.
+-- 'validate' should be an underapproximation of actual validity.
 --
 -- This means that if 'isValid' is not a perfect representation of actual
 -- validity, for safety reasons, it should never return 'True' for invalid
@@ -120,18 +128,18 @@
 --
 -- For example:
 --
--- > isValid = const False
+-- > validate = const $ invalid "always"
 --
--- is a valid implementation for any type, because it never returns 'True'
--- for invalid values.
+-- is a valid implementation for any type, because now 'isValid' never returns
+-- 'True' for invalid values.
 --
--- > isValid (Even i) = i == 2
+-- > validate (Even i) = declare "The integer is equal to two" $ i == 2
 --
 -- is a valid implementation for @newtype Even = Even Int@, but
 --
--- > isValid (Even i) = even i || i == 1
+-- > validate (Even i) = declare "The integer is even or equal to one" $ even i || i == 1
 --
--- is not because it returns 'True' for an invalid value: '1'.
+-- is not because then `isValid` returns 'True' for an invalid value: '1'.
 --
 -- === Automatic instances with 'Generic'
 --
@@ -154,16 +162,16 @@
 --
 -- > instance Validity MyType where
 -- >     validate (MyType d s)
--- >         = d <?!> "myDouble"
--- >        <> s <?!> "myString"
+-- >         = annotate d "myDouble"
+-- >        <> annotate s "myString"
 class Validity a where
     validate :: a -> Validation
     default validate :: (Generic a, GValidity (Rep a)) =>
         a -> Validation
-    validate = gValidate . from
+    validate = genericValidate
 
-isValid :: Validity a => a -> Bool
-isValid = isRight . checkValidity
+genericValidate :: (Generic a, GValidity (Rep a)) => a -> Validation
+genericValidate = gValidate . from
 
 data ValidationChain
     = Violated String
@@ -426,6 +434,7 @@
         mconcat
             [ declare "The Float is not Nan." $ not (isNaN f)
             , declare "The Float is not infinite." $ not (isInfinite f)
+            , declare "The Float is not zegative zero." $ not (isNegativeZero f)
             ]
 
 -- | NOT trivially valid:
@@ -437,6 +446,7 @@
         mconcat
             [ declare "The Double is not NaN." $ not (isNaN d)
             , declare "The Double is not infinite." $ not (isInfinite d)
+            , declare "The Double is not zegative zero." $ not (isNegativeZero d)
             ]
 
 -- | Trivially valid
@@ -454,7 +464,7 @@
 --
 -- Only available with @base >= 4.8@.
 instance Validity Natural where
-    validate n = check (isValidNatural n) "The Natural is valid."
+    validate = declare "The Natural is valid." . isValidNatural
 #endif
 -- | Valid if the contained numbers are valid and the denominator is
 -- strictly positive.
@@ -503,7 +513,11 @@
 instance (Validity a) => GValidity (K1 R a) where
     gValidate (K1 x) = validate x
 
--- | Check whether 'isInvalid' is not valid.
+-- | Check whether a value is valid.
+isValid :: Validity a => a -> Bool
+isValid = isRight . checkValidity
+
+-- | Check whether a value is not valid.
 --
 -- > isInvalid = not . isValid
 isInvalid :: Validity a => a -> Bool
diff --git a/test/Data/ValiditySpec.hs b/test/Data/ValiditySpec.hs
--- a/test/Data/ValiditySpec.hs
+++ b/test/Data/ValiditySpec.hs
@@ -1,13 +1,14 @@
 {-# LANGUAGE DeriveGeneric #-}
+{-# LANGUAGE CPP #-}
 
 module Data.ValiditySpec
     ( spec
     ) where
 
 import GHC.Generics (Generic)
-
+#if !MIN_VERSION_base(4,11,0)
 import Data.Monoid
-
+#endif
 import Data.Validity
 
 import Test.Hspec
diff --git a/validity.cabal b/validity.cabal
--- a/validity.cabal
+++ b/validity.cabal
@@ -1,11 +1,11 @@
--- This file has been generated from package.yaml by hpack version 0.20.0.
+-- This file has been generated from package.yaml by hpack version 0.28.2.
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: 0352fc096299ba22bf145acdce658a27d3bf5898a040f8b0829d6aaa82332fd2
+-- hash: bf53a19ba2c00de66db95f83937a6950f4b805b648cadb0e7f4a224b954970f6
 
 name:           validity
-version:        0.6.0.0
+version:        0.7.0.0
 synopsis:       Validity typeclass
 description:    For more info, see <https://github.com/NorfairKing/validity the readme>.
                 .
@@ -34,7 +34,8 @@
 homepage:       https://github.com/NorfairKing/validity#readme
 bug-reports:    https://github.com/NorfairKing/validity/issues
 author:         Tom Sydney Kerckhove
-maintainer:     syd.kerckhove@gmail.com
+maintainer:     syd.kerckhove@gmail.com,
+                nick.van.den.broeck666@gmail.com
 copyright:      Copyright: (c) 2016-2018 Tom Sydney Kerckhove
 license:        MIT
 license-file:   LICENSE