diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,3 +1,7 @@
+# Since 1.0.6
+
+* Upgrade Diff dependency to 0.4
+
 # Since 1.0.5
 
 * Allow merging a specific file
diff --git a/git-mediate.cabal b/git-mediate.cabal
--- a/git-mediate.cabal
+++ b/git-mediate.cabal
@@ -2,7 +2,7 @@
 -- further documentation, see http://haskell.org/cabal/users-guide/
 
 name:                git-mediate
-version:             1.0.6
+version:             1.0.7
 synopsis:            Tool to help resolving git conflicts
 description:         Git conflict resolution has never been easier
                      .
@@ -78,7 +78,7 @@
                      , process >=1.2
                      , filepath >=1.3
                      , unix-compat >=0.4.2.0
-                     , Diff >=0.3
+                     , Diff >=0.4
                      , ansi-terminal >=0.6.2
                      , optparse-applicative >=0.11 && <0.15
   hs-source-dirs:      src
diff --git a/src/PPDiff.hs b/src/PPDiff.hs
--- a/src/PPDiff.hs
+++ b/src/PPDiff.hs
@@ -3,7 +3,7 @@
   , ppDiff
   ) where
 
-import Data.Algorithm.Diff (Diff(..))
+import Data.Algorithm.Diff (Diff, PolyDiff(..))
 import System.Console.ANSI
 
 data ColorEnable = EnableColor | DisableColor