diff --git a/README.md b/README.md
index 5cc5976..92aa73c 100644
--- a/README.md
+++ b/README.md
@@ -86,5 +86,5 @@ class MyChat implements MessageComponentInterface {
     // Then some JavaScript in the browser:
     var conn = new WebSocket('ws://localhost:8080/echo');
     conn.onmessage = function(e) { console.log(e.data); };
-    conn.send('Hello Me!');
-```
\ No newline at end of file
+    conn.onopen = function(e) { conn.send('Hello Me!'); };
+```
diff --git a/composer.json b/composer.json
index 80a3aa5..6ce02b3 100644
--- a/composer.json
+++ b/composer.json
@@ -29,4 +29,7 @@
       , "symfony/http-foundation": "^2.2|^3.0"
       , "symfony/routing": "^2.2|^3.0"
     }
+  , "require-dev": {
+        "phpunit/phpunit": "~4.8"
+    }
 }