diff --git a/docs/developer.md b/docs/developer.md
index ea2e36ce1..0546c20e9 100644
--- a/docs/developer.md
+++ b/docs/developer.md
@@ -363,7 +363,7 @@ from pathlib import Path
 exchange = ccxt.binance({
     'apiKey': '<apikey>',
     'secret': '<secret>'
-    'options': {'defaultType': 'future'}
+    'options': {'defaultType': 'swap'}
     })
 _ = exchange.load_markets()