add markdown badges to the readme

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 797ea91..c4120a0 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md

@@ -1,3 +1,6 @@
+## 3.0.3-dev
+
+
 ## 3.0.2
 
 * Fix bug in `CodePage` class. See issue [#47](https://github.com/dart-lang/convert/issues/47).

diff --git a/README.md b/README.md
index 9a832fd..47392cb 100644
--- a/README.md
+++ b/README.md

@@ -1,6 +1,15 @@
-# Conversion utilities package
+[![Dart CI](https://github.com/dart-lang/convert/actions/workflows/test-package.yml/badge.svg)](https://github.com/dart-lang/convert/actions/workflows/test-package.yml)
+[![pub package](https://img.shields.io/pub/v/convert.svg)](https://pub.dev/packages/convert)
+[![package publisher](https://img.shields.io/pub/publisher/convert.svg)](https://pub.dev/packages/convert/publisher)
+
+Utilities for converting between data representations.
+
+## Conversion utilities package
 
 This package contains encoders and decoders for converting between different
 data representations. It's the external counterpart of the `dart:convert` core
 library, and contains less-central APIs and APIs that need more flexible
 versioning.
+
+See also
+[api.dart.dev/dart-convert](https://api.dart.dev/stable/dart-convert/dart-convert-library.html).

diff --git a/analysis_options.yaml b/analysis_options.yaml
index 85d6c12..162fc08 100644
--- a/analysis_options.yaml
+++ b/analysis_options.yaml

@@ -1,4 +1,5 @@
 include: package:lints/recommended.yaml
+
 analyzer:
   strong-mode:
     implicit-casts: false

diff --git a/pubspec.yaml b/pubspec.yaml
index ad683ae..d3997a7 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml

@@ -1,5 +1,5 @@
 name: convert
-version: 3.0.2
+version: 3.0.3-dev
 description: >-
   Utilities for converting between data representations.
   Provides a number of Sink, Codec, Decoder, and Encoder types.