Keith Cirkel

OSS & Web Standards Developer

Contact

About

OSS Contributor for projects including Sass, Chai & Babel. Contributor to JavaScript and HTML specifications. Proven track record of delivering solutions.

Work

Mozilla

Staff Software Engineer - DOM Core
2025-04-15 - Present

Building the core engine of Firefox, developing new features in the web platform and shipping code to over 200,000,000 customers.Building the core engine of Firefox, developing new features in the web platform and shipping code to over 200,000,000 customers.

GitHub

Senior Application Engineer
2017-06-06 - 2025-04-11

Worked on platform systems teams delivering GitHub.com's JavaScript & UI components, to over 100,000,000 customers. Built industry leading components in GitHub's Primer design system - a modern, clean and accessible UI design system.

Keith Cirkel LTD

Owner
2011-03-01 - 2017-06-02

Consultancy company leading teams to success. Clients included Max Factor, Financial Times, The Economist, Kingfisher PLC, PhotoBox, BSkyB, British Gas (Centrica), EA, LexisNexis (Elsevier). Delivered solutions for clients following Agile principles, with strong TDD. Technologies included Node.JS, React, Chai, Redis, Varnish.Consultancy company leading teams to success. Delivered solutions for clients following Agile principles, with strong TDD. Technologies included Node.JS, React, Chai, Redis, Varnish.

Xcite Digital

Head of Creative
2010-04-01 - 2011-03-01

Lead Frontend Developer, turned Head of Creative, working with many key clients. Developed and maintained large income client projects developed in Symfony 1.4, utilising jQuery for all frontend interactivity. Involved in key technical decisions, liaising with clients and suppliers and organising and managing other team members. Managed a series of virtual dedicated Linux servers, running Cherokee web server with MySQL and PHP. Introduced GIT to the team with no existing version control.

BrightHue

Owner
2007-08-01 - 2010-04-01

Digital Agency developing & designing sites & solutions for clients using PHP, MySQL, Javascript & jQuery. Managed and maintained virtual dedicated servers running a LAMP stack.

Freelancer
2003-01-01 - 2007-01-01

Worked with small clients developing and maintaining websites utilising technologies such as PHP, MySQL, Javascript & MooFX.

Volunteer

CodeClub

Teacher
2013-01-01 - Present

Mentoring 9-11 year old pupils on how to program, using the Scratch programming environment.