diff --git a/composer.json b/composer.json
index 8d4119cd..f18e9e71 100644
--- a/composer.json
+++ b/composer.json
@@ -2,7 +2,7 @@
 	"require-dev": {
 		"jakub-onderka/php-parallel-lint": "1.0.0",
 		"jakub-onderka/php-console-highlighter": "0.3.2",
-		"mediawiki/mediawiki-codesniffer": "20.0.0",
+		"mediawiki/mediawiki-codesniffer": "21.0.0",
 		"mediawiki/minus-x": "0.3.1",
 		"mediawiki/mediawiki-phan-config": "0.3.0"
 	},