Asterisk open source VOIP PBX developer

We're looking for a developer with excellent experience of the Asterisk open source VOIP phone system. Essentially what we're looking to develop are a selection of PHP scripts which will expose functionality of the system and allow us to interact with the underlying .conf files (e.g. [login to view URL], [login to view URL] etc) from external applications. For example one script might be: (to create a new extension) http://server/[login to view URL] Essentially the job is to create this API type interface to expose the common features of Asterisk, specifically Extensions, SIP trunks, Voicemail, Music on hold, Auto attendant. We will also need scripts to retrieve call records from the MySQL DB in XML format. Thanks