Thanks for mentioning this. Also keep in mind that mapzen its isochrone API: https://github.com/valhalla/valhalla https://github.com/valhalla/valhalla as well

Thanks for mentioning this. Also keep in mind that mapzen its isochrone API: https://github.com/valhalla/valhalla https://github.com/valhalla/valhalla as well as ours is open source: https://github.com/graphhopper/graphhopper/pull/1237 https://github.com/graphhopper/graphhopper/pull/1237