diff --git a/.travis.yml b/.travis.yml
index fc4547b..43b18fb 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -20,7 +20,7 @@ script:
   - composer validate --no-check-all --strict
   - mkdir -p build/logs
   - vendor/bin/phpunit --testsuite=integration
-  - vendor/bin/phpunit --testsuite=unit --coverage-text  --coverage-clover build/logs/clover.xml
+  - XDEBUG_MODE=coverage vendor/bin/phpunit --testsuite=unit --coverage-text  --coverage-clover build/logs/clover.xml
   - bash .githooks/pre-commit
   - php tests/systemTests.php