Two children are born the same night in 1900, three houses apart. One of them is you. Deathday plays the century in five minutes: every few years you get one card and two choices, and history arrives on a fixed calendar whether you like it or not. Every run ends in a tombstone you can engrave and share, next to the other child's. It's live at deathday.online.
WHAT'S DONE
Ten birthplaces so far: Bengal, Galicia, the Ohio Valley, Shandong, Queensland, São Paulo, the Gold Coast, Java, Egypt and the Uzbek SSR. Each has its own 1900 mortality table, its own dated events, its own communities with weights from contemporary census data, and its own other child. Over 340 cards, and each one carries a source; if a card can't be sourced, it doesn't ship. Three modes: a Daily with one shared birth for everyone in the world and one attempt, a ninety-second Blitz, and Free play. It runs as a PWA, works offline, and uses Supabase for handles and the daily board. Built on Vite, React and TypeScript with the engine kept pure and unit-tested, so a daily seed replays identically for every player.
THE DECISION THAT SHAPED IT
Most life sims give you a health bar, a wealth number, a happiness meter. Deathday tracks four things: the year, the place, what you chose, and whether you are alive. That constraint is the honesty mechanism. The mortality tables are calibrated so the simulated mean age at death matches each region's real 1900 life expectancy, which means about four in ten Bengal or Shandong lives end before age five, because that is what 1900 was. A stat you could grind would let you argue with that. A card with two small, human choices and a stated probability of death can't be argued with, only lived. Historian's notes with sources sit one tap from every tombstone, so when the game kills you, it can show its working.
WHAT'S NEXT
More regions (Punjab, the Rhineland and Minas Gerais are the candidates), and a look at whether the daily comparison lines, the "68% crossed the line in 1947" kind, are the thing that makes people come back or just a nice number.