diff --git a/repos/os/include/pin_state_session/connection.h b/repos/os/include/pin_state_session/connection.h
index e223123ffa..535a419f85 100644
--- a/repos/os/include/pin_state_session/connection.h
+++ b/repos/os/include/pin_state_session/connection.h
@@ -16,6 +16,7 @@
 
 #include <pin_state_session/pin_state_session.h>
 #include <base/connection.h>
+#include <base/rpc_client.h>
 
 namespace Pin_state { struct Connection; }