Aptana Jaxer provides a page-processing environment based on the Mozilla engine. This provides a Gecko-based DOM and SpiderMonkey JavaScript engine to allow pages to be rendered and manipulated on the server before being sent to the browser. Jaxer also provides an Ajax model for performing asynchronous requests to the server. Its client and server APIs allow such requests to be made by simply calling server-side JavaScript functions from the client. Behind the scenes, Jaxer provides the logic required to manage the request and retrieve the response from the server.