diff --git a/Git/S3.hs b/Git/S3.hs
--- a/Git/S3.hs
+++ b/Git/S3.hs
@@ -563,8 +563,7 @@
                             (RequestBodyLBS lbs))
             void $ readResponseIO res
 
-type RefMap m =
-    M.HashMap Text (Maybe (Git.Reference (LgRepository m) (Commit m)))
+type RefMap m = M.HashMap Text (Maybe (Git.Reference (LgRepository m)))
 
 -- jww (2013-04-26): Split these off into a gitlib-aeson library.
 instance A.FromJSON (Reference m) where
@@ -576,7 +575,7 @@
                           <*> (Git.RefSymbolic <$> o .: "target")
             Nothing -> Git.Reference
                            <$> o .: "name"
-                           <*> (Git.RefObj . Git.ByOid . go <$> o .: "target")
+                           <*> (Git.RefObj . go <$> o .: "target")
       where
         go = return . mkOid . unsafePerformIO . strToOid
 
@@ -584,13 +583,9 @@
   toJSON (Git.Reference name (Git.RefSymbolic target)) =
       object [ "symbolic" .= name
              , "target"   .= target ]
-  toJSON (Git.Reference name (Git.RefObj (Git.ByOid oid))) =
+  toJSON (Git.Reference name (Git.RefObj oid)) =
       object [ "name"   .= name
              , "target" .= coidToJSON (getOid (unTagged oid)) ]
-  toJSON (Git.Reference name (Git.RefObj (Git.Known commit))) =
-      object [ "name"   .= name
-             , "target" .=
-               coidToJSON (getOid (unTagged (Git.commitOid commit))) ]
 
 readRefs :: Ptr C'git_odb_backend -> IO (Maybe (RefMap m))
 readRefs be = do
@@ -634,7 +629,7 @@
                     c'git_reference_symbolic_create ptr repoPtr namePtr
                         targetPtr 1
             Just Git.Reference {
-                Git.referenceTarget = Git.RefObj (Git.ByOid (Tagged coid)) } ->
+                Git.referenceTarget = Git.RefObj (Tagged coid) } ->
                 withForeignPtr (getOid coid) $ \coidPtr ->
                     c'git_reference_create ptr repoPtr namePtr coidPtr 1
             _ -> return 0
diff --git a/gitlib-s3.cabal b/gitlib-s3.cabal
--- a/gitlib-s3.cabal
+++ b/gitlib-s3.cabal
@@ -1,5 +1,5 @@
 Name:                gitlib-s3
-Version:             1.3.1
+Version:             1.4.0
 Synopsis:            Gitlib repository backend for storing Git objects in Amazon S3
 Description:         Gitlib repository backend for storing Git objects in Amazon S3.
 License-file:        LICENSE
@@ -22,10 +22,10 @@
   hs-source-dirs: test
   build-depends:
       base >=3
-    , gitlib             >= 1.3.1
-    , gitlib-s3          >= 1.3.1
-    , gitlib-test        >= 1.3.1
-    , gitlib-libgit2     >= 1.3.1
+    , gitlib             >= 1.4.0
+    , gitlib-s3          >= 1.4.0
+    , gitlib-test        >= 1.4.0
+    , gitlib-libgit2     >= 1.4.0
     , hlibgit2           >= 0.18.0.7
     , aws                >= 0.7.5
     , HUnit              >= 1.2.5
@@ -45,8 +45,8 @@
   default-language: Haskell98
   build-depends:
       base                 >= 3 && < 5
-    , gitlib               >= 1.3.1
-    , gitlib-libgit2       >= 1.3.1
+    , gitlib               >= 1.4.0
+    , gitlib-libgit2       >= 1.4.0
     , ghc-prim
     , hlibgit2             >= 0.18.0.1
     , HUnit                >= 1.2.5