diff --git a/AUTHORS.md b/AUTHORS.md
index c516ca30..925eb91a 100644
--- a/AUTHORS.md
+++ b/AUTHORS.md
@@ -7,6 +7,7 @@ Sinatra was designed and developed by Blake Mizerany in California.
 * **Kashyap Kondamudi**
 * **Ashley Williams**
 * **Trevor Bramble**
+* **Kunpei Sakai**
 
 ### Alumni