diff --git a/core-writer/test/mock/stream.cpp b/core-writer/test/mock/stream.hpp
similarity index 91%
rename from core-writer/test/mock/stream.cpp
rename to core-writer/test/mock/stream.hpp
index a7b00d9..c0a690f 100644
--- a/core-writer/test/mock/stream.cpp
+++ b/core-writer/test/mock/stream.hpp
@@ -1,3 +1,6 @@
+#ifndef MOCK_STREAM_H
+#define MOCK_STREAM_H
+
 #include <zmq.hpp>
 
 void generate_stream(size_t n_messages)
@@ -17,4 +20,6 @@ void generate_stream(size_t n_messages)
         socket.send(header_msg, zmq::send_flags::sndmore);
         socket.send(buffer_msg);
     }
-}
\ No newline at end of file
+}
+
+#endif
\ No newline at end of file
diff --git a/core-writer/test/test_ZmqRecvModule.cpp b/core-writer/test/test_ZmqRecvModule.cpp
index f4d99f7..f56ceba 100644
--- a/core-writer/test/test_ZmqRecvModule.cpp
+++ b/core-writer/test/test_ZmqRecvModule.cpp
@@ -5,7 +5,7 @@
 #include <string>
 #include "RingBuffer.hpp"
 
-#include "mock/stream.cpp"
+#include "mock/stream.hpp"
 
 using namespace std;