diff --git a/pubspec.yaml b/pubspec.yaml
index d06ce879..08842798 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,4 +1,6 @@
 name: angel_cache
+environment:
+  sdk: ">=1.19.0 <=2.0.0"
 dependencies:
   angel_framework: ">=1.0.0-dev <2.0.0"
   intl: ^0.15.0