diff --git a/CHANGELOG.md b/CHANGELOG.md
index f970830..1d02eea 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,3 +14,7 @@ Breaking api changes: Result.ok, Result.err
 # 0.4.0
 
 Breaking api changes: removed ResultType enum from api
+
+# 0.5.0
+
+Changed dart version to 2.12
diff --git a/pubspec.yaml b/pubspec.yaml
index 24229c9..0b60619 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,11 +1,11 @@
 name: okay
 description: Typesafe error-handling for dart . An implementation of rust's `Result` type in dart.
-version: 0.4.0
+version: 0.5.0
 homepage: https://hextools.0xba1.xyz
 repository: https://github.com/0xba1/okay.git
 
 environment:
-  sdk: ">=2.17.0 <3.0.0"
+  sdk: ">=2.12.0 <3.0.0"
 
 dependencies:
   meta: ^1.7.0