diff --git a/pubspec.yaml b/pubspec.yaml
index 174820c..0ce9b2a 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,6 +1,9 @@
 name: mime
+version: 0.9.0
 author: Dart Team <misc@dartlang.org>
 description: Helper-package for working with MIME.
 homepage: http://www.dartlang.org
 dev_dependencies:
-  unittest: any
+  unittest: ">=0.9.0 <0.10.0"
+environment:
+  sdk: ">=0.8.10+6 <2.0.0"