diff --git a/x/async.md b/x/io/README.md
similarity index 99%
rename from x/async.md
rename to x/io/README.md
index 314a3b7a..f5585c58 100644
--- a/x/async.md
+++ b/x/io/README.md
@@ -1,4 +1,4 @@
-# Async Design
+# Async I/O Design
 
 ## Async functions in different languages