Stellwerk

Stellwerk is an open-ended railway signalling puzzle — a Zachlike game involving switches, signals and timetables.

You don't drive the trains. Instead, you lay the track, place the switches and signals, configure the routes, and then hit Start to watch everything unfold. If you get the layout right, every train on the schedule will reach its destination on time, collision-free and without deadlock, with no live input required. Get it wrong, however, and the game will stop and tell you exactly where and why, providing information such as which train is waiting on which block, which signal stayed red and where two routes deadlocked.

The Timetable:
This is where all the trains are listed, along with their departure times.

Sandbox. Once you have completed the campaign, you are taken to a free-build sandbox where you start on a blank, resizable board. Place your own sources, sinks and timetable and connect them however you like. It uses the same editor and deterministic simulation as before, but with no goals or scoring. Build or solve anything, then share it as a short text code that can be pasted back in and replayed identically.

Build,  run, debug, optimize. A level is solved once the trains have passed through; then the real game begins. Three scoring axes (throughput, material and punctuality) transform each puzzle into an optimisation problem. The norm is one solution per axis; nailing all three at once is the masterclass.

This is an early demo (Chapter 1) — feedback very welcome.