diff --git a/f8/coroutine.cc b/f8/coroutine.cc
index 1c8796d..a4cb486 100644
--- a/f8/coroutine.cc
+++ b/f8/coroutine.cc
@@ -1,3 +1,4 @@
+#ifdef USE_BOOST
 #include <a8/a8.h>
 #include <a8/awaiter.h>
 #include <a8/promise.h>
@@ -7,8 +8,6 @@
 #include <f8/comgr.h>
 #include <f8/timer.h>
 
-#ifdef USE_BOOST
-
 class TimerPromise : public a8::Promise
 {
  public:
diff --git a/f8/coroutine.h b/f8/coroutine.h
index 97f345b..5a529e8 100644
--- a/f8/coroutine.h
+++ b/f8/coroutine.h
@@ -1,9 +1,7 @@
 #pragma once
 
-#include <a8/awaiter.h>
-
 #ifdef USE_BOOST
-
+#include <a8/awaiter.h>
 #include <boost/coroutine2/all.hpp>
 
 namespace f8