The code behind my blog post.
Requires a Project OSRM HTTP instance running, and some OpenStreetMap data. I used California.osm.pbf from Geofabrik, and docker for OSRM:
docker run
-p 5000:5000
--name osrm-api
-v ~/biking-to-work/profile.lua:/osrm-build/profile.lua
-v ~/biking-to-work/osrm-data/:/osrm-data/
cartography/osrm-backend-docker:latest
osrm
California