Engines
Four processes sit behind the static HTML. The browser talks HTTPS to DREGG and onboard. It never talks to Zakura RPC.
DREGG
Checkout, prices, pay-targets, mint after payment.
Zakura
House Zcash node and compact streamer. The wallet is svg-mint-zrt, not zcash-devtool.
Feegrant runtime
Runtime authz → HashMerchant → one-time customer grant.
Smart-account onboard
passkey-grant after paid commitment.