Operation Stack Sats on Nostr: The tech powering this is called Spark — a Bitcoin L2 that validates transactions ...

The tech powering this is called Spark — a Bitcoin L2 that validates transactions at broadcast time. Spark checks for double-spend risk, fee adequacy, and replace-by-fee flags before the transaction even hits a block. Then it credits your Polymarket balance in under a second. Zero-conf, but with real validation behind it.