diff --git a/server/robotserver/coroutine.cc b/server/robotserver/coroutine.cc
index 9b048f6c..dd072ae6 100644
--- a/server/robotserver/coroutine.cc
+++ b/server/robotserver/coroutine.cc
@@ -10,6 +10,11 @@ void Awaiter::Await(std::shared_ptr<Awaiter> parent)
 
 }
 
+void Promise::Await(std::shared_ptr<Awaiter> parent)
+{
+
+}
+
 Coroutine::Coroutine(std::function<void(Coroutine*)> cb)
 {
     INIT_LIST_HEAD(&co_entry_);
@@ -101,3 +106,8 @@ void Coroutine::CallExit(boost::coroutines2::coroutine<void>::push_type& sink)
 {
     sink_ = nullptr;
 }
+
+void Coroutine::Await(std::shared_ptr<Awaiter> parent)
+{
+
+}
diff --git a/server/robotserver/coroutine.h b/server/robotserver/coroutine.h
index f40e9ee9..9f6ac2d9 100644
--- a/server/robotserver/coroutine.h
+++ b/server/robotserver/coroutine.h
@@ -37,7 +37,6 @@ protected:
     virtual void Await(std::shared_ptr<Awaiter> parent);
 
  private:
-    std::shared_ptr<Awaiter> parent_;
     bool done_ = false;
     std::shared_ptr<a8::Results> results_;
     std::function<void()> cb_;
@@ -46,7 +45,12 @@ protected:
 
 class Promise : public Awaiter
 {
+protected:
 
+    virtual void Await(std::shared_ptr<Awaiter> parent) override;
+
+ private:
+    std::shared_ptr<Awaiter> parent_;
 };
 
 class Coroutine : public Awaiter
@@ -67,6 +71,7 @@ class Coroutine : public Awaiter
     void Deatch();
     void CallEnter(boost::coroutines2::coroutine<void>::push_type& sink);
     void CallExit(boost::coroutines2::coroutine<void>::push_type& sink);
+    virtual void Await(std::shared_ptr<Awaiter> parent) override;
 
  private:
     list_head co_entry_;