add badges to README.md

README.md

@@ -1,4 +1,14 @@
 # seaport-types
+
+[![Version][version-badge]][version-link]
+[![npm][npm-badge]][npm-link]
+
 This repo contains the core Seaport structs, enums, and interfaces for use in other Seaport repos.
 
-For more information on Seaport, see the [main Seaport repo](https://github.com/ProjectOpenSea/seaport).
+For more information on Seaport, see the [main Seaport repo][seaport-link].
+
+[seaport-link]: https://github.com/ProjectOpenSea/seaport
+[version-badge]: https://img.shields.io/github/package-json/v/ProjectOpenSea/seaport-types
+[version-link]: https://github.com/ProjectOpenSea/seaport-types/releases
+[npm-badge]: https://img.shields.io/npm/v/seaport-types?color=red
+[npm-link]: https://www.npmjs.com/package/seaport-types