Prepare to publish (#410)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 50fa3f6..a171b31 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,7 +1,7 @@
-## 0.12.1-dev
+## 0.12.1
 
 * Add `IOStreamedResponse` which includes the ability to detach the socket.
-  When sending a request with an `IOClient` the response will be an 
+  When sending a request with an `IOClient` the response will be an
   `IOStreamedResponse`.
 * Remove dependency on `package:async`.
 
diff --git a/pubspec.yaml b/pubspec.yaml
index cf75877..a3e1f1c 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,5 +1,5 @@
 name: http
-version: 0.12.1-dev
+version: 0.12.1
 homepage: https://github.com/dart-lang/http
 description: A composable, multi-platform, Future-based API for HTTP requests.