Looking for programmer for SIP VoIP communications, WebRTC, PBX and Pine64

We are looking for a programmer with experience in working with audio/video (A/V) SIP VoIP communications using WebRTC and WebRTC mobile, call managed through a PBX (preferably Asterisks). The first and main engineering task is to establish A/V SIP VoIP communications from a Pine64 SBC running Linux Armbian through a Web Browser to a smartphone (iOS/Android). Asterisks and the WebRTC services are to exist in the Cloud. After the successful completion of the above task, we would also like the to establish a connection from the Pine64 to a windows 10 PC (running the Chrome web browser). The objective of this project is to create a reliable communications path accessible to other developers through API calls at each point. These other developers would develop Web/Node.js, iOS, Andriod APPS and required call an API to initiate A/V communications. Program installation, configuration and API code will be managed on the Jira, Confluence bitbucket platform. We will have the Pine64 setup in our lab with the OS installed and a camera, speaker and microphone attached. Remote access will be provided. Task Details: To establish voice video communications between the following: 1) Pine64 Running the installed Armbian Linux OS and Web Browser with WebRTC. A button in the browser will simulate a directory listing. Upon pressing this button, the browser will open a window on the browser to show an image from the camera connected to the Pine64. The Browser will then use WebRTC to connect to the Asterisks PBX in the Cloud with a WebRTC server to connect to a smartphone also running Mobile WebRTC in the Android OS. The smartphone will display video only in the Android APP, unit a Button is pressed to accept the call. Then a one-way video, two-way audio communications will occur. We would like to be able to adjust the framerate and resolution on the PINE 64 to provide a consistent QOS. 2) Same as above with two-way video. 3) Same as above, except communications is to a Windows 10 PC running a web browser (Chrome) The Pine64 board we have: [login to view URL]