diff --git a/engine/src/flutter/tools/licenses/pubspec.yaml b/engine/src/flutter/tools/licenses/pubspec.yaml
index 7274384324..91ba3b11b7 100644
--- a/engine/src/flutter/tools/licenses/pubspec.yaml
+++ b/engine/src/flutter/tools/licenses/pubspec.yaml
@@ -5,3 +5,5 @@ dependencies:
   crypto: ^2.0.2+1
   meta: ^1.1.6
   path: ^1.3.0
+environment:
+  sdk: '>=2.3.0 <3.0.0'