john-sierraI’m John Gorenfeld, a San Francisco writer, author and consulting Web/iOS app programmer with a background in the media industry.

As a developer, I build, document and advise clients on how best to implement:

* JavaScript framework applications (React, Angular, Backbone, Node)

* iOS apps (Swift, Objective-C)

Tech portfolio here; drop me a line for rates and estimates. No job too small (or large)