diff --git a/pubspec.yaml b/pubspec.yaml
index bc691bb..3df006e 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -6,7 +6,7 @@ authors:
 homepage: https://github.com/xqwzts/feedparser
 
 environment:
-  sdk: '>=1.21.0 <2.0.0'
+  sdk: '>=2.0.0-dev.58.0 <3.0.0'
 
 dependencies:
   xml: "^3.0.0-alpha"