Digitransit architecture is based on microservices architecture. Microservices are small, autonomous services that work together that allow us to build larger applications on top of APIs that the services provide.
At the moment, we provide five kinds of services
Real time API is more or less "work in progress". HSL is working on new Ticketing system and at the moment realtime API (arrival prediction, location on map, service alerts) is in "proof of concept" stage.
Data containers are images that are used to gather and compile data needed for APIs by the platform. Read more here
External compoments are something that Digitransit depends on. Someone else than us takes care that they work.