diff --git a/Data/PQueue/Internals.hs b/Data/PQueue/Internals.hs
--- a/Data/PQueue/Internals.hs
+++ b/Data/PQueue/Internals.hs
@@ -97,7 +97,7 @@
   Empty `compare` Empty = EQ
   Empty `compare` _ = LT
   _ `compare` Empty = GT
-  MinQueue n1 x1 q1 `compare` MinQueue n2 x2 q2 = compare x1 x2 `mappend` cmp' q1 q2 where
+  MinQueue _n1 x1 q1 `compare` MinQueue _n2 x2 q2 = compare x1 x2 `mappend` cmp' q1 q2 where
     cmp' q1 q2 = case (extractHeap q1, extractHeap q2) of
       (Just (x1, q1'), Just (x2, q2'))
         -> compare x1 x2 `mappend` cmp' q1' q2'
diff --git a/Data/PQueue/Max.hs b/Data/PQueue/Max.hs
--- a/Data/PQueue/Max.hs
+++ b/Data/PQueue/Max.hs
@@ -36,6 +36,7 @@
   getMax,
   deleteMax,
   deleteFindMax,
+  delete,
   maxView,
   -- * Construction operations
   singleton,
diff --git a/Data/PQueue/Min.hs b/Data/PQueue/Min.hs
--- a/Data/PQueue/Min.hs
+++ b/Data/PQueue/Min.hs
@@ -1,4 +1,5 @@
 {-# LANGUAGE CPP #-}
+{-# OPTIONS_GHC -fno-warn-orphans #-}
 
 -----------------------------------------------------------------------------
 -- |
diff --git a/Data/PQueue/Prio/Internals.hs b/Data/PQueue/Prio/Internals.hs
--- a/Data/PQueue/Prio/Internals.hs
+++ b/Data/PQueue/Prio/Internals.hs
@@ -27,7 +27,8 @@
   foldrWithKeyU,
   foldlWithKeyU,
   traverseWithKeyU,
-  seqSpine
+  seqSpine,
+  mapForest
   ) where
 
 import Control.Applicative (Applicative(..), (<$>))
@@ -101,7 +102,7 @@
 infixr 6 <>
 
 instance (Ord k, Ord a) => Ord (MinPQueue k a) where
-  MinPQ n1 k1 a1 ts1 `compare` MinPQ n2 k2 a2 ts2 =
+  MinPQ _n1 k1 a1 ts1 `compare` MinPQ _n2 k2 a2 ts2 =
     k1 `compare` k2 <> a1 `compare` a2 <> ts1 `cmpHeap` ts2
    where
     ts1 `cmpHeap` ts2 = case (extract ts1, extract ts2) of
@@ -318,7 +319,7 @@
 data MExtract rk k a = No | Yes {-# UNPACK #-} !(Extract rk k a)
 
 incrExtract :: LEq k -> Maybe (BinomTree rk k a) -> Extract (Succ rk) k a -> Extract rk k a
-incrExtract (<=) Nothing (Extract k a (Succ t ts) tss)
+incrExtract _    Nothing (Extract k a (Succ t ts) tss)
   = Extract k a ts (Cons t tss)
 incrExtract (<=) (Just t) (Extract k a (Succ t' ts) tss)
   = Extract k a ts (Skip (incr (<=) (meld (<=) t t') tss))
diff --git a/Data/PQueue/Prio/Max.hs b/Data/PQueue/Prio/Max.hs
--- a/Data/PQueue/Prio/Max.hs
+++ b/Data/PQueue/Prio/Max.hs
@@ -1,4 +1,5 @@
 {-# LANGUAGE CPP #-}
+{-# OPTIONS_GHC -fno-warn-orphans #-}
 
 -----------------------------------------------------------------------------
 -- |
@@ -140,9 +141,6 @@
 first' :: (a -> b) -> (a, c) -> (b, c)
 first' f (a, c) = (f a, c)
 
-second' :: (b -> c) -> (a, b) -> (a, c)
-second' f (a, b) = (a, f b)
-
 instance Ord k => Monoid (MaxPQueue k a) where
   mempty = empty
   mappend = union
@@ -439,13 +437,13 @@
 -- | /O(n)/.  An unordered traversal over a priority queue, in no particular order.
 -- While there is no guarantee in which order the elements are traversed, the resulting
 -- priority queue will be perfectly valid.
-traverseU :: (Applicative f, Ord b) => (a -> f b) -> MaxPQueue k a -> f (MaxPQueue k b)
+traverseU :: (Applicative f) => (a -> f b) -> MaxPQueue k a -> f (MaxPQueue k b)
 traverseU = traverseWithKeyU . const
 
 -- | /O(n)/.  An unordered traversal over a priority queue, in no particular order.
 -- While there is no guarantee in which order the elements are traversed, the resulting
 -- priority queue will be perfectly valid.
-traverseWithKeyU :: (Applicative f, Ord b) => (k -> a -> f b) -> MaxPQueue k a -> f (MaxPQueue k b)
+traverseWithKeyU :: (Applicative f) => (k -> a -> f b) -> MaxPQueue k a -> f (MaxPQueue k b)
 traverseWithKeyU f (MaxPQ q) = MaxPQ <$> Q.traverseWithKeyU (f . unDown) q
 
 -- | /O(n)/.  Return all keys of the queue in no particular order.
diff --git a/Data/PQueue/Prio/Min.hs b/Data/PQueue/Prio/Min.hs
--- a/Data/PQueue/Prio/Min.hs
+++ b/Data/PQueue/Prio/Min.hs
@@ -1,4 +1,5 @@
 {-# LANGUAGE CPP #-}
+{-# OPTIONS_GHC -fno-warn-orphans #-}
 
 -----------------------------------------------------------------------------
 -- |
@@ -137,12 +138,6 @@
 
 (.:) :: (c -> d) -> (a -> b -> c) -> a -> b -> d
 (f .: g) x y = f (g x y)
-
-first' :: (a -> b) -> (a, c) -> (b, c)
-first' f (a, c) = (f a, c)
-
-second' :: (b -> c) -> (a, b) -> (a, c)
-second' f (a, b) = (a, f b)
 
 uncurry' :: (a -> b -> c) -> (a, b) -> c
 uncurry' f (a, b) = f a b
diff --git a/pqueue.cabal b/pqueue.cabal
--- a/pqueue.cabal
+++ b/pqueue.cabal
@@ -1,5 +1,5 @@
 Name:               pqueue
-Version:            1.3.1
+Version:            1.3.1.1
 Category:           Data Structures
 Author:             Louis Wasserman
 License:            BSD3
@@ -13,13 +13,17 @@
 Build-type:         Simple
 cabal-version:      >= 1.6
 extra-source-files: include/Typeable.h
+tested-with:        GHC == 7.0.4, GHC == 7.2.2, GHC == 7.6.3, GHC == 7.8.4, GHC == 7.10.1, GHC == 8.0.1
 
 source-repository head
   type: git
   location: git@github.com:lspitzner/pqueue.git
 
 Library {
-  build-depends: base >= 4 && < 4.9, deepseq
+  build-depends:
+  { base >= 4 && < 4.10
+  , deepseq >= 1.3 && < 1.5
+  }
   exposed-modules:
     Data.PQueue.Prio.Min
     Data.PQueue.Prio.Max
@@ -33,5 +37,15 @@
   if impl(ghc) {
     extensions: DeriveDataTypeable
   }
-  ghc-options: -fdicts-strict
+  ghc-options: {
+    -fdicts-strict
+    -Wall
+    -fno-warn-name-shadowing
+    -fno-warn-unused-imports
+  }
+ if impl(ghc>=7.8) {
+  ghc-options: {
+    -fno-warn-inline-rule-shadowing
+  }
+ }
 }