diff --git a/implementations/onblocks/cachingdatatreestore/CachingDataTreeStore.h b/implementations/onblocks/cachingdatatreestore/CachingDataTreeStore.h
index dc92c5e3..afa7acd1 100644
--- a/implementations/onblocks/cachingdatatreestore/CachingDataTreeStore.h
+++ b/implementations/onblocks/cachingdatatreestore/CachingDataTreeStore.h
@@ -5,10 +5,8 @@
 #include <memory>
 #include <messmer/cpp-utils/macros.h>
 #include <messmer/cachingstore/CachingStore.h>
+#include <messmer/blockstore/utils/Key.h>
 
-namespace blockstore{
-class Key;
-}
 namespace blobstore {
 namespace onblocks {
 namespace datatreestore {
diff --git a/implementations/onblocks/datanodestore/DataInnerNode_ChildEntry.h b/implementations/onblocks/datanodestore/DataInnerNode_ChildEntry.h
index 3b4e010c..3b2c9bec 100644
--- a/implementations/onblocks/datanodestore/DataInnerNode_ChildEntry.h
+++ b/implementations/onblocks/datanodestore/DataInnerNode_ChildEntry.h
@@ -18,7 +18,7 @@ private:
     key.ToBinary(_keydata);
   }
   friend class DataInnerNode;
-  uint8_t _keydata[blockstore::Key::KEYLENGTH_BINARY];
+  uint8_t _keydata[blockstore::Key::BINARY_LENGTH];
   DISALLOW_COPY_AND_ASSIGN(DataInnerNode_ChildEntry);
 };
 
diff --git a/implementations/onblocks/datanodestore/DataNodeStore.h b/implementations/onblocks/datanodestore/DataNodeStore.h
index bf340628..04925dfa 100644
--- a/implementations/onblocks/datanodestore/DataNodeStore.h
+++ b/implementations/onblocks/datanodestore/DataNodeStore.h
@@ -5,11 +5,11 @@
 #include <memory>
 #include "messmer/cpp-utils/macros.h"
 #include "DataNodeView.h"
+#include <messmer/blockstore/utils/Key.h>
 
 namespace blockstore{
 class Block;
 class BlockStore;
-class Key;
 }
 
 namespace blobstore {
diff --git a/implementations/onblocks/datatreestore/DataTree.h b/implementations/onblocks/datatreestore/DataTree.h
index e0b98bc3..af047e41 100644
--- a/implementations/onblocks/datatreestore/DataTree.h
+++ b/implementations/onblocks/datatreestore/DataTree.h
@@ -8,10 +8,8 @@
 #include "../datanodestore/DataNodeView.h"
 //TODO Replace with C++14 once std::shared_mutex is supported
 #include <boost/thread/shared_mutex.hpp>
+#include <messmer/blockstore/utils/Key.h>
 
-namespace blockstore {
-class Key;
-}
 namespace blobstore {
 namespace onblocks {
 namespace datanodestore {
diff --git a/implementations/onblocks/datatreestore/DataTreeStore.h b/implementations/onblocks/datatreestore/DataTreeStore.h
index 02772aab..54e4c24b 100644
--- a/implementations/onblocks/datatreestore/DataTreeStore.h
+++ b/implementations/onblocks/datatreestore/DataTreeStore.h
@@ -4,10 +4,8 @@
 
 #include <memory>
 #include <messmer/cpp-utils/macros.h>
+#include <messmer/blockstore/utils/Key.h>
 
-namespace blockstore{
-class Key;
-}
 namespace blobstore {
 namespace onblocks {
 namespace datanodestore {
diff --git a/interface/Blob.h b/interface/Blob.h
index d400148d..48a72286 100644
--- a/interface/Blob.h
+++ b/interface/Blob.h
@@ -4,10 +4,7 @@
 
 #include <cstring>
 #include <cstdint>
-
-namespace blockstore {
-class Key;
-}
+#include <messmer/blockstore/utils/Key.h>
 
 namespace blobstore {