diff --git a/.travis.yml b/.travis.yml
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,4 +1,58 @@
-language: haskell
+# NB: don't set `language: haskell` here
+
+# See also https://github.com/hvr/multi-ghc-travis for more information
+env:
+ # we have to use CABALVER=1.16 for GHC<7.6 as well, as there's
+ # no package for earlier cabal versions in the PPA
+ - GHCVER=7.4.2 CABALVER=1.16
+ - GHCVER=7.6.3 CABALVER=1.16
+ - GHCVER=7.8.4 CABALVER=1.18
+ - GHCVER=7.10.1 CABALVER=1.22
+ - GHCVER=head CABALVER=1.22
+
+matrix:
+  allow_failures:
+   - env: GHCVER=head CABALVER=1.22
+
+# Note: the distinction between `before_install` and `install` is not
+#       important.
+before_install:
+ - travis_retry sudo add-apt-repository -y ppa:hvr/ghc
+ - travis_retry sudo apt-get update
+ - travis_retry sudo apt-get install cabal-install-$CABALVER ghc-$GHCVER
+ - export PATH=/opt/ghc/$GHCVER/bin:/opt/cabal/$CABALVER/bin:$PATH
+ - cabal --version
+
+install:
+ - travis_retry cabal update
+ - cabal install --only-dependencies
+ - travis_retry sudo apt-get -q -y install hlint || cabal install hlint
+
+# Here starts the actual work to be performed for the package under
+# test; any command which exits with a non-zero exit code causes the
+# build to fail.
+script:
+ # -v2 provides useful information for debugging
+ - cabal configure -v2
+
+ # this builds all libraries and executables
+ # (including tests/benchmarks)
+ - cabal build
+
+ # tests that a source-distribution can be generated
+ - cabal sdist
+ - hlint src --cpp-define HLINT
+
+ # check that the generated source-distribution can be built & installed
+ - export SRC_TGZ=$(cabal info . | awk '{print $2 ".tar.gz";exit}') ;
+   cd dist/;
+   if [ -f "$SRC_TGZ" ]; then
+      cabal install --force-reinstalls "$SRC_TGZ";
+   else
+      echo "expected '$SRC_TGZ' not found";
+      exit 1;
+   fi
+
 notifications:
   irc:
     channels:
diff --git a/CHANGELOG.markdown b/CHANGELOG.markdown
--- a/CHANGELOG.markdown
+++ b/CHANGELOG.markdown
@@ -1,3 +1,8 @@
+0.3.2
+-----
+* Build without warnings on GHC 7.10
+* Overload Foldable `null` and `length` on GHC 7.10+
+
 0.3.1
 -----
 * Explicit nominal role annotation
diff --git a/heaps.cabal b/heaps.cabal
--- a/heaps.cabal
+++ b/heaps.cabal
@@ -1,5 +1,5 @@
 name:           heaps
-version:        0.3.1
+version:        0.3.2
 license:        BSD3
 license-file:   LICENSE
 author:         Edward A. Kmett
@@ -11,6 +11,7 @@
 synopsis:       Asymptotically optimal Brodal/Okasaki heaps.
 description:    Asymptotically optimal Brodal/Okasaki bootstrapped skew-binomial heaps from the paper <http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.48.973 "Optimal Purely Functional Priority Queues">, extended with a 'Foldable' interface.
 copyright:      (c) 2010 Edward A. Kmett
+tested-with:    GHC == 7.4.2, GHC == 7.6.3, GHC == 7.8.4, GHC == 7.10.0.20150307
 build-type:     Simple
 cabal-version:  >=1.8
 extra-source-files: .travis.yml CHANGELOG.markdown README.markdown
diff --git a/src/Data/Heap.hs b/src/Data/Heap.hs
--- a/src/Data/Heap.hs
+++ b/src/Data/Heap.hs
@@ -79,10 +79,15 @@
     ) where
 
 import Prelude hiding
-    ( map, null
+    ( map
     , span, dropWhile, takeWhile, break, filter, take, drop, splitAt
     , foldr, minimum, replicate, mapM
     , concatMap
+#if __GLASGOW_HASKELL__ < 710
+    , null
+#else
+    , traverse
+#endif
     )
 import qualified Data.List as L
 import Control.Applicative (Applicative(pure))
@@ -163,31 +168,7 @@
       go f (_:_) [] = GT
 
 
--- | /O(1)/. Is the heap empty?
---
--- >>> null empty
--- True
---
--- >>> null (singleton "hello")
--- False
-null :: Heap a -> Bool
-null Empty = True
-null _ = False
-{-# INLINE null #-}
 
--- | /O(1)/. The number of elements in the heap.
---
--- >>> size empty
--- 0
--- >>> size (singleton "hello")
--- 1
--- >>> size (fromList [4,1,2])
--- 3
-size :: Heap a -> Int
-size Empty = 0
-size (Heap s _ _) = s
-{-# INLINE size #-}
-
 -- | /O(1)/. The empty heap
 --
 -- @'empty' ≡ 'fromList' []@
@@ -414,6 +395,39 @@
 instance Foldable Heap where
   foldMap _ Empty = mempty
   foldMap f l@(Heap _ _ t) = f (root t) `mappend` foldMap f (deleteMin l)
+#if __GLASGOW_HASKELL__ >= 710
+  null Empty = True
+  null _ = False
+
+  length = size
+#else
+
+-- | /O(1)/. Is the heap empty?
+--
+-- >>> null empty
+-- True
+--
+-- >>> null (singleton "hello")
+-- False
+null :: Heap a -> Bool
+null Empty = True
+null _ = False
+{-# INLINE null #-}
+
+#endif
+
+-- | /O(1)/. The number of elements in the heap.
+--
+-- >>> size empty
+-- 0
+-- >>> size (singleton "hello")
+-- 1
+-- >>> size (fromList [4,1,2])
+-- 3
+size :: Heap a -> Int
+size Empty = 0
+size (Heap s _ _) = s
+{-# INLINE size #-}
 
 -- | /O(n)/. Map a function over the heap, returning a new heap ordered appropriately for its fresh contents
 --