Usetaxstream

Usetaxstream (branded as 'Peper') is a sales tax nexus analysis tool for accounting firms. It ingests client invoice/transaction data, calculates state-by-state economic nexus exposure using statutory lookback periods, applies exemptions, and generates PDF reports for accountants to deliver to their clients. Built on Wix. Appears to be an early-stage/bootstrapped tool rather than a full embedded-finance platform.