"Budapest's new e-ticketing system uses state-of-the-art JavaScript to deliver a smooth user experience, combining a great React front-end with a micro-services node.js backend!" - marketing blurb I just made up, needs more buzzwords though.
...stateless cloud interactive real-time connection through highly sophisticated authentication featuring dual way private/public key encryption services with single use time-limited tokens ...
Don't forget the blockchain! It needs more blockchain! ;-)
Also wouldn't mind some "cyber" in there :D
... cyberspace with optional IoT interfacing ...
(I had completely forgotten IoT)
... seamlessly integrated via blockchain into ...
You have to wonder why they didn't hire a security tester. Just for 10 minutes or so.