diff --git a/websockets.scm b/websockets.scm
index 1e676b6..51d9692 100644
--- a/websockets.scm
+++ b/websockets.scm
@@ -166,6 +166,7 @@
      outbound-port)
 
     (write-string data len outbound-port)
+   (flush-output (response-port (current-response)))
     #t))
 
 (define (send-message data #!optional (optype 'text) (ws (current-websocket)))