diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7793cfcc85ecc9cb0bcf70cc75e24c60823da8d5..353e88399270ea098b65a857ecece7f34dca8d0e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -57,6 +57,7 @@ ADD_PROJECT_DEPENDENCY(sot-core REQUIRED)
 
 # Main Library
 set(${PROJECT_NAME}_HEADERS
+  include/${PROJECT_NAME}/fwd.hh
   include/${PROJECT_NAME}/ros_init.hh
   include/${PROJECT_NAME}/sot_loader.hh
   include/${PROJECT_NAME}/sot_loader_basic.hh
diff --git a/include/dynamic_graph_bridge/fwd.hh b/include/dynamic_graph_bridge/fwd.hh
new file mode 100644
index 0000000000000000000000000000000000000000..0a98b01c690693cec5550ef9d4b49a4387919651
--- /dev/null
+++ b/include/dynamic_graph_bridge/fwd.hh
@@ -0,0 +1,20 @@
+/*
+ * Copyright CNRS 2021
+ *
+ * Author: Florent Lamiraux
+ *
+ * This file is part of sot-core.
+ */
+
+#ifndef DYNAMIC_GRAPH_BRIDGE_FWD_HH
+#define DYNAMIC_GRAPH_BRIDGE_FWD_HH
+
+#include <dynamic-graph/python/fwd.hh>
+
+namespace dynamicgraph {
+  // classes defined in sot-core
+  class Interpreter;
+  typedef shared_ptr<Interpreter> InterpreterPtr_t;
+}// namespace dynamicgraph
+
+#endif // DYNAMIC_GRAPH_PYTHON_FWD_HH
diff --git a/include/dynamic_graph_bridge/ros_interpreter.hh b/include/dynamic_graph_bridge/ros_interpreter.hh
index 31da180602edce5a48176423109501e04dae5bf4..1eacc9e5b375f0aec2f6532079d024e4efd36f3d 100644
--- a/include/dynamic_graph_bridge/ros_interpreter.hh
+++ b/include/dynamic_graph_bridge/ros_interpreter.hh
@@ -5,6 +5,7 @@
 #include <ros/ros.h>
 #pragma GCC diagnostic pop
 
+#include <dynamic_graph_bridge/fwd.hh>
 #include <dynamic_graph_bridge_msgs/RunCommand.h>
 #include <dynamic_graph_bridge_msgs/RunPythonFile.h>
 #include <dynamic-graph/python/interpreter.hh>