diff --git a/composer.json b/composer.json
index c797bb2..2063cee 100644
--- a/composer.json
+++ b/composer.json
@@ -19,14 +19,14 @@
 	},
 	"require":{
 		"php":">=5.3",
-		"contao/core":">=3.0",
+		"contao/core":">=3.0||<5",
 		"contao-community-alliance/composer-plugin": "~2.0"
 	},
 	"replace": {
-		"cgo-it/xls_export": "self.version"
+		"cgo-it/xls_export": "3.0.0"
 	},
     "conflict": {
-			"contao/core": "2.11.*"
+			"contao/core": "<=2.11.*"
 	},
 	"extra":{
 		"contao": {
@@ -35,4 +35,4 @@
 			}
 		}
 	}
-}
\ No newline at end of file
+}