Required Visualization,JSON,Sass,CSS,Web Apps freelancer for Front-End Development job

I am looking for a junior to mid-level front end developer to help with a number of very exciting high-profile project. The project involves data visualisation and animations at major sporting events. To begin with we need someone for a 1 month period with a strong likely hood of extension to at least 3 months. We have Ruby and Javascript expertise in house and are looking for an extra pair of hands to get these projects done.

Key skills
* Javascript
* CSS3 and Sass
* HTML5

Other useful skills
* Ruby on Rails
* D3.js
* Greensocks javascript library
* JQuery

Skills & Expertise Required

Visualization JSON Sass CSS Web Apps