Every ~2 s the beacon hashes live plasma. Pick one hash, and this page grows a small world from it.
The hash decides which cells are born. Thirty-two steps of Conway’s Game of Life later, the entire history is folded into one fingerprint. The same pulse always grows the same world — so any world born here can be re-grown and checked, anywhere, forever.
Runs entirely in your browser · same algorithm as the Rail reference implementation · fingerprints must match bit-for-bit
Cells live or die by Conway’s rules on a 40×20 wrap-around grid. Below the board, every generation is folded into a running SHA-256 chain — the ledger is the world’s diary, and the final line commits all of it.
A world’s birth certificate is just its pulse number and pulse hash. Paste one below — yours from earlier, or a friend’s — and the same world unfolds again. If the fingerprint at the end matches the original, nothing about that history was altered. That’s the whole trick: not trust me, check me.
accepts “pulse hash”, “pulse:hash”, or a full seed string
Born from whatever pulse was live the first time you opened this page, and aged only as the beacon ticks — one generation every 128 pulses, about four minutes. Close the tab for a week and it comes back a week older. It is recomputed from its birth certificate on every visit, so nobody — not you, not us — can age it faster, wind it back, or swap it out.
The pulse hash is stretched by SHA-256 into 800 bytes; each byte decides one cell. Nobody draws the starting pattern — the world is the hash.
Conway’s rules run 32 generations. No randomness anywhere: the future was already implied the moment the pulse landed. Running it doesn’t create the history — it discovers it.
Each generation is folded into a SHA-256 chain. Reorder, skip, or retouch any frame and every later fingerprint changes. The head is a 32-byte name for the entire history.
This page recomputes two reference worlds on load — produced independently by the Rail implementation — and shows whether your browser agrees: