diff --git a/app/backend/computermanager.h b/app/backend/computermanager.h
index 510f975d..b8f45f40 100644
--- a/app/backend/computermanager.h
+++ b/app/backend/computermanager.h
@@ -18,6 +18,8 @@
 #include <QMutex>
 #include <QWaitCondition>
 
+class ComputerManager;
+
 class DelayedFlushThread : public QThread
 {
     Q_OBJECT