At Mapzen, all our code is open source, from front-end UIs to back-end "glue." Have a look at: - web and mobile SDKs: http://github.com/mapzen/ http://github.c

At Mapzen, all our code is open source, from front-end UIs to back-end "glue." Have a look at: - web and mobile SDKs: http://github.com/mapzen/ http://github.com/mapzen/ - map rendering library: http://github.com/tangrams http://github.com/tangrams - map tiles: https://github.com/tilezen/ https://github.com/tilezen/ - routing/navigation: https://github.com/valhalla/ https://github.com/valhalla/ - public transit: https://github.com/transitland/ https://github.com/transitland/ - search/geocoding: http://github.com/pelias http://github.com/pelias - gazetteer: https://github.com/whosonfirst https://github.com/whosonfirst FWIW, we do have a few private repos, to protect some ops internals as well as upcoming blog posts. (I work at Mapzen -- and am also a happy user of Mapbox's open-source libraries.)