In this talk I will cover how to create a REST API using Grails 2.3 to support single-page applications, exploring all the possible alternatives. Code is available at https://github.com/alvarosanchez/restful-grails-springsecurity-greach2014 I will also explain how to integrate Spring Security using the spring-security-rest plugin I recently created, to implement a stateless, token-based, RESTful authentication.