diff --git a/composer.json b/composer.json
index 91acbc3..00144ea 100644
--- a/composer.json
+++ b/composer.json
@@ -28,7 +28,8 @@
 		"ext-libxml": "*",
 		"ext-xmlreader": "*",
 		"ext-zip": "*",
-		"php": "^7.4"
+		"php": "^7.4",
+		"nulib/php": "^0.6.0p74"
 	},
 	"require-dev": {
 		"nulib/tests": "^7.4",