diff --git a/test/run_all.sh b/test/run_all.sh
index db04b50f..7d8c6edd 100755
--- a/test/run_all.sh
+++ b/test/run_all.sh
@@ -11,7 +11,7 @@ fi
 whitely echo ...ok
 
 TESTS="${@:-$(find "$DIR" -name '*_test.sh')}"
-RUNNER_ARGS=""
+RUNNER_ARGS=${RUNNER_ARGS:-""}
 
 # If running on circle, use the scheduler to work out what tests to run
 if [ -n "$CIRCLECI" -a -z "$NO_SCHEDULER" ]; then