diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Changelog
 
+#### 0.34.0.1
+
+* Fix for base 4.8/GHC 7.10.
+
 ## 0.34
 
 * Allow setting the method in the requests in a top level multi
diff --git a/rest-core.cabal b/rest-core.cabal
--- a/rest-core.cabal
+++ b/rest-core.cabal
@@ -1,5 +1,5 @@
 name:                rest-core
-version:             0.34
+version:             0.34.0.1
 description:         Rest API library.
 synopsis:            Rest API library.
 maintainer:          code@silk.co
@@ -39,7 +39,7 @@
     Rest.Schema
     Rest.ShowUrl
   build-depends:
-      base >= 4.5 && < 4.8
+      base >= 4.5 && < 4.9
     , aeson >= 0.7 && < 0.9
     , aeson-utils == 0.2.*
     , bytestring >= 0.9 && < 0.11
@@ -69,7 +69,7 @@
   main-is:           Runner.hs
   type:              exitcode-stdio-1.0
   build-depends:
-      base >= 4.5 && < 4.8
+      base >= 4.5 && < 4.9
     , HUnit == 1.2.*
     , bytestring >= 0.9 && < 0.11
     , mtl >= 2.0 && < 2.3
diff --git a/src/Rest/Driver/Perform.hs b/src/Rest/Driver/Perform.hs
--- a/src/Rest/Driver/Perform.hs
+++ b/src/Rest/Driver/Perform.hs
@@ -283,6 +283,7 @@
     try None FileFormat      = throwError (UnsupportedFormat (show FileFormat))
     try (Dicts ds) f = tryD ds f
       where
+        tryD :: [Output v] -> Format -> ErrorT DataError m ()
         tryD (XmlO       : _ ) XmlFormat    = return ()
         tryD (RawXmlO    : _ ) XmlFormat    = return ()
         tryD (JsonO      : _ ) JsonFormat   = return ()
@@ -306,6 +307,7 @@
     try None MultipartFormat = contentType NoFormat >> ok ""
     try (Dicts ds) f = tryD ds f
       where
+        tryD :: [Output v] -> Format -> ErrorT DataError m UTF8.ByteString
         tryD (XmlO       : _ ) XmlFormat    = contentType XmlFormat    >> ok (UTF8.fromString (toXML v))
         tryD (RawXmlO    : _ ) XmlFormat    = contentType XmlFormat    >> ok v
         tryD (JsonO      : _ ) JsonFormat   = contentType JsonFormat   >> ok (encode v)