diff --git a/arangod/Aql/ExecutionState.cpp b/arangod/Aql/ExecutionState.cpp
new file mode 100644
index 0000000000..4e788e5655
--- /dev/null
+++ b/arangod/Aql/ExecutionState.cpp
@@ -0,0 +1,46 @@
+////////////////////////////////////////////////////////////////////////////////
+/// DISCLAIMER
+///
+/// Copyright 2018-2018 ArangoDB GmbH, Cologne, Germany
+///
+/// Licensed under the Apache License, Version 2.0 (the "License");
+/// you may not use this file except in compliance with the License.
+/// You may obtain a copy of the License at
+///
+///     http://www.apache.org/licenses/LICENSE-2.0
+///
+/// Unless required by applicable law or agreed to in writing, software
+/// distributed under the License is distributed on an "AS IS" BASIS,
+/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+/// See the License for the specific language governing permissions and
+/// limitations under the License.
+///
+/// Copyright holder is ArangoDB GmbH, Cologne, Germany
+///
+/// @author Jan Steemann
+////////////////////////////////////////////////////////////////////////////////
+
+#include "ExecutionState.h"
+
+#include <ostream>
+
+namespace arangodb {
+namespace aql {
+
+std::ostream& operator<<(std::ostream& ostream, ExecutionState state) {
+  switch (state) {
+    case ExecutionState::DONE:
+      ostream << "DONE";
+      break;
+    case ExecutionState::HASMORE:
+      ostream << "HASMORE";
+      break;
+    case ExecutionState::WAITING:
+      ostream << "WAITING";
+      break;
+  }
+  return ostream;
+}
+
+}  // namespace aql
+}  // namespace arangodb
diff --git a/arangod/Aql/ExecutionState.h b/arangod/Aql/ExecutionState.h
index 84e78091b1..0ac112b92a 100644
--- a/arangod/Aql/ExecutionState.h
+++ b/arangod/Aql/ExecutionState.h
@@ -23,7 +23,7 @@
 #ifndef ARANGOD_AQL_EXECUTION_STATE_H
 #define ARANGOD_AQL_EXECUTION_STATE_H 1
 
-#include <ostream>
+#include <iosfwd>
 
 namespace arangodb {
 namespace aql {
@@ -42,20 +42,7 @@ enum class ExecutionState {
   WAITING
 };
 
-inline std::ostream& operator<<(std::ostream& ostream, ExecutionState state) {
-  switch (state) {
-    case ExecutionState::DONE:
-      ostream << "DONE";
-      break;
-    case ExecutionState::HASMORE:
-      ostream << "HASMORE";
-      break;
-    case ExecutionState::WAITING:
-      ostream << "WAITING";
-      break;
-  }
-  return ostream;
-}
+std::ostream& operator<<(std::ostream& ostream, ExecutionState state);
 
 }  // namespace aql
 }  // namespace arangodb
diff --git a/arangod/Aql/IndexHint.cpp b/arangod/Aql/IndexHint.cpp
index 9021f59d7d..b99e5fbec9 100644
--- a/arangod/Aql/IndexHint.cpp
+++ b/arangod/Aql/IndexHint.cpp
@@ -30,6 +30,8 @@
 #include "Basics/StaticStrings.h"
 #include "Basics/VelocyPackHelper.h"
 
+#include <ostream>
+
 namespace {
 std::string const TypeIllegal("illegal");
 std::string const TypeNone("none");
diff --git a/arangod/Aql/IndexHint.h b/arangod/Aql/IndexHint.h
index 69acce300b..a6e50d37d9 100644
--- a/arangod/Aql/IndexHint.h
+++ b/arangod/Aql/IndexHint.h
@@ -24,7 +24,7 @@
 #ifndef ARANGOD_AQL_INDEX_HINT_H
 #define ARANGOD_AQL_INDEX_HINT_H 1
 
-#include <iostream>
+#include <iosfwd>
 
 #include <velocypack/Builder.h>
 #include <velocypack/Slice.h>
diff --git a/arangod/CMakeLists.txt b/arangod/CMakeLists.txt
index 28204b87f3..339a495c41 100644
--- a/arangod/CMakeLists.txt
+++ b/arangod/CMakeLists.txt
@@ -214,6 +214,7 @@ SET(ARANGOD_SOURCES
   Aql/ExecutionEngine.cpp
   Aql/ExecutionNode.cpp
   Aql/ExecutionPlan.cpp
+  Aql/ExecutionState.cpp
   Aql/ExecutionStats.cpp
   Aql/ExecutorExpressionContext.cpp
   Aql/ExecutorInfos.cpp