1 files changed, 1 insertions, 1 deletions
diff --git a/examples/echo_server.ts b/examples/echo_server.ts
index 95b9f7413..970df4f8d 100644
--- a/examples/echo_server.ts
+++ b/examples/echo_server.ts
@@ -1,7 +1,7 @@
 // Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
 const { listen, copy } = Deno;
 
-(async () => {
+(async (): Promise<void> => {
   const addr = "0.0.0.0:8080";
   const listener = listen("tcp", addr);
   console.log("listening on", addr);