diff --git a/pubspec.yaml b/pubspec.yaml
index 06c39ae7..5cd03915 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -3,7 +3,7 @@ description: angel_auth strategy for OAuth2 login, i.e. Facebook.
 version: 1.0.2
 author: Tobe O <thosakwe@gmail.com>
 environment:
-  sdk: ">=1.19.0"
+  sdk: ">=1.19.0 <3.0.0"
 homepage: https://github.com/angel-dart/auth_oauth2.git
 dependencies:
   angel_auth: ^1.0.0-dev