diff --git a/composer.json b/composer.json
index bef0c76..346000e 100644
--- a/composer.json
+++ b/composer.json
@@ -7,13 +7,14 @@
 		"silverstripe/framework": "self.version",
 		"silverstripe/reports": "self.version",
 		"silverstripe/siteconfig": "self.version",
-		"silverstripe-themes/simple": "*"
+		"silverstripe-themes/simple": "3.1.*"
 	},
 	"require-dev": {
-		"phpunit/PHPUnit": "~3.7@stable"
+		"phpunit/PHPUnit": "~3.7"
 	},
 	"config": {
 		"process-timeout": 600
 	},
+	"prefer-stable": true,
 	"minimum-stability": "dev"
 }