diff --git a/php/psalm.xml b/php/psalm.xml
index 576d82d2..7449f28f 100644
--- a/php/psalm.xml
+++ b/php/psalm.xml
@@ -1,5 +1,6 @@
 <?xml version="1.0"?>
 <psalm
+	errorLevel="1"
 	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 	xmlns="https://getpsalm.org/schema/config"
 	xsi:schemaLocation="https://getpsalm.org/schema/config vendor/vimeo/psalm/config.xsd"