Deadline
One global platformer, identical for everyone on Earth and generated from today's date. When any player dies, their corpse freezes into the level for all players, in realtime.
Problem#
Most multiplayer games are about beating other people. I wanted the opposite: a game where you cannot win alone, where the people who fail before you are the reason you get through. Deaths become the terrain.
Constraints#
- Every player, worldwide, must see the exact same level on a given day, with no central level server dictating it.
- A death anywhere should show up for everyone within a second or two.
- It has to survive a level littered with tens of thousands of corpses without dropping frames.
Build#
The level is generated client-side from a seed derived from the UTC date, so everyone gets an identical gauntlet that resets at 00:00 UTC. A Dijkstra pass computes the minimum number of corpses needed to clear the day's barriers, which means a solo player physically cannot finish. It takes a crowd.
When you die, the corpse is broadcast through Supabase Realtime and persisted, then it becomes climbable geometry and spike-pit filler for everyone else. Rendering that many bodies stays cheap by baking them into chunked offscreen canvases, and each corpse travels as a 13-byte binary record so snapshots stay small and CDN-cacheable. Cosmetic peer broadcasts are unvalidated for speed; the persisted record is server-validated so a faked death cannot corrupt the shared state.
Result#
A daily ritual with genuine emergent cooperation, running on free infrastructure and holding a steady frame rate under a six-figure corpse count. It is the project I point to when someone asks about realtime systems and determinism.