Ian Johnson is a data visualization programmer and designer based in San Francisco. His passion is building tools that make the creation of visual, and data-driven media more intuitive and engaging for both programmers and non-programmers alike. As an active user in the d3.js community, he co-organizes the SF Bay Area d3 Meetup and hones his data vis engineering skills at lever.co. Ian develops http://tributary.io in his spare time to help people prototype their d3.js visualizations quicker.