diff --git a/pubspec.yaml b/pubspec.yaml
index f26176c..65e43b9 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,7 +1,9 @@
 name: mustache
-version: 0.1.5
+version: 0.1.6
 author: Greg Lowe <greg@vis.net.nz>
 description: Mustache template library
 homepage: https://github.com/xxgreg/mustache
+environment:
+  sdk: ">=0.8.10+6 <2.0.0"
 dev_dependencies:
-  unittest: any
\ No newline at end of file
+  unittest: ">=0.9.0 <0.10.0"
\ No newline at end of file