diff --git a/engine/src/flutter/.ci.yaml b/engine/src/flutter/.ci.yaml
index 869db0a4282..75a5ae280ac 100644
--- a/engine/src/flutter/.ci.yaml
+++ b/engine/src/flutter/.ci.yaml
@@ -160,7 +160,7 @@ targets:
       framework: "true"
       shard: web_tests
       subshards: >-
-              [0, 1, 2, 3, 4, 5, 6, 7_last]
+              ["0", "1", "2", "3", "4", "5", "6", "7_last"]
     timeout: 60
     scheduler: luci
     runIf: