diff --git a/composer.json b/composer.json
index 51530b4..33b9a75 100644
--- a/composer.json
+++ b/composer.json
@@ -62,7 +62,7 @@
         "check": "phpcs --standard=PSR2 src test",
         "test": [
             "@check",
-            "php ./bin/phpunit"
+            "TRELLIS_CONFIG_DIR=test/resources/config php ./bin/phpunit"
         ]
     },
     "conflict": {