All stages · Demo 397

Belgian enterprise

Choice be / vat / other. Ten digits; last two = 97 minus first eight mod 97. Jev never mods 97. Nine digits need 10.

ChoiceBE 97 in JS

A digit tape. 0123456749 books a KBO plate. A last-digit flip rejects. Nine digits never pass.

replaykind —be —

STANDBY

All 4056 stages

Educational stage on jev.page — not the official TypeSafe console. Live calls go to POST https://api.typesafe.ai/v1/systemone from your browser when you paste a key. Without a key, the stage plays a recorded decision shaped like jev-1.13.0. Jev does not write the UI copy.