diff --git a/grid.cabal b/grid.cabal
--- a/grid.cabal
+++ b/grid.cabal
@@ -1,5 +1,5 @@
 Name:              grid
-Version:           7.8.1
+Version:           7.8.2
 Stability:         experimental
 Synopsis:          Tools for working with regular grids (graphs, lattices).
 Description:       Provides tools for working with regular arrangements
@@ -27,12 +27,12 @@
 source-repository this
   type:     git
   location: https://github.com/mhwombat/grid.git
-  tag:      7.8.1
+  tag:      7.8.2
 
 
 library
   hs-source-dirs:  src
-  build-depends:   base ==4.* && >= 4.8,
+  build-depends:   base ==4.*,
                    cereal ==0.4.*,
                    containers ==0.5.*
   ghc-options:     -Wall
@@ -53,7 +53,7 @@
 
 test-suite grid-tests
   type:            exitcode-stdio-1.0
-  build-depends:   base ==4.* && >= 4.8,
+  build-depends:   base ==4.*,
                    containers ==0.5.*,
                    test-framework-quickcheck2 ==0.3.*,
                    QuickCheck ==2.7.*,
diff --git a/src/Math/Geometry/GridMap.hs b/src/Math/Geometry/GridMap.hs
--- a/src/Math/Geometry/GridMap.hs
+++ b/src/Math/Geometry/GridMap.hs
@@ -12,7 +12,10 @@
 -- @'Data.Map'@, in order to combine the functionality of grids and maps
 -- into a single type.
 ------------------------------------------------------------------------
-{-# LANGUAGE TypeFamilies, FlexibleContexts, MultiParamTypeClasses #-}
+{-# LANGUAGE TypeFamilies #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE MultiParamTypeClasses #-}
+{-# LANGUAGE CPP #-}
 
 module Math.Geometry.GridMap
   (
@@ -32,6 +35,11 @@
 import Prelude hiding (lookup, map, foldr, foldl, foldr1, foldl1, null)
 import qualified Data.Map as M
 import qualified Math.Geometry.Grid as G
+
+#if MIN_VERSION_base(4,8,0)
+#else
+import Data.Foldable (Foldable)
+#endif
 
 -- | A regular arrangement of tiles, having a value associated with
 --   each tile.