All stages · Demo 246

EAN-8

Choice grocery / pharma / other. EAN-8 is eight digits with a 3-1 check from the left. Jev never weights them. Seven digits need 8.

ChoiceEAN-8 checksum in JS

Barcode pips. 96385074 scans grocery. A last-digit flip rejects. A short pack rejects on length.

replaykind —ean —

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.