diff --git a/Git/Sample.hs b/Git/Sample.hs
--- a/Git/Sample.hs
+++ b/Git/Sample.hs
@@ -15,7 +15,7 @@
        ( SampleRepository(..), Repository(..)
        , Git.Oid, BlobOid(), TreeOid(), CommitOid()
        , Tree(), Commit()
-       , TreeRef(), CommitRef(), Reference()
+       , Reference()
        , sampleFactory
        , sampleGet
        ) where
@@ -100,11 +100,7 @@
 
 type Tree m      = Git.Tree (SampleRepository m)
 type Commit m    = Git.Commit (SampleRepository m)
-
-type TreeRef m   = Git.TreeRef (SampleRepository m)
-type CommitRef m = Git.CommitRef (SampleRepository m)
-
-type Reference m = Git.Reference (SampleRepository m) (Commit m)
+type Reference m = Git.Reference (SampleRepository m)
 
 sampleGet :: Monad m => SampleRepository m Repository
 sampleGet = SampleRepository ask
diff --git a/gitlib-sample.cabal b/gitlib-sample.cabal
--- a/gitlib-sample.cabal
+++ b/gitlib-sample.cabal
@@ -1,5 +1,5 @@
 Name:                gitlib-sample
-Version:             1.3.1
+Version:             1.4.0
 Synopsis:            Sample backend for gitlib showing the basic structure for any backend.
 License-file:        LICENSE
 License:             MIT
@@ -22,9 +22,9 @@
 --     Hs-source-dirs: test
 --     Build-depends: 
 --           base >=3
---         , gitlib             >= 1.3.1
---         , gitlib-test        >= 1.3.1
---         , gitlib-sample      >= 1.3.1
+--         , gitlib             >= 1.4.0
+--         , gitlib-test        >= 1.4.0
+--         , gitlib-sample      >= 1.4.0
 --         , HUnit              >= 1.2.5
 --         , hspec              >= 1.4.4
 --         , hspec-expectations >= 0.3
@@ -34,7 +34,7 @@
     ghc-options: -Wall
     build-depends:
           base                 >= 3 && < 5
-        , gitlib               >= 1.3.1
+        , gitlib               >= 1.4.0
         , failure              >= 0.2.0.1
         , system-filepath      >= 0.4.7
         , tagged               >= 0.2.3.1