diff --git a/.gitignore b/.gitignore
index ee0e074..3d6cbd0 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,4 +2,5 @@ doc/
 doc-diagram/
 doc-video/
 bin/*
+!bin/empty_file
 
diff --git a/bin/empty_file b/bin/empty_file
new file mode 100644
index 0000000..e69de29