Sierra

Verification notes: Re-checked this pass. Payment capability remains confirmed: Sierra's Level 1 PCI-DSS compliant payment capability (card and ACH collection directly in chat/voice, without a hold or IVR handoff) launched in April 2026 and is listed on the Visa Global Service Provider Registry. Cardholder data runs through dedicated PCI-certified infrastructure separate from Sierra's core platform. A version removing the current Twilio dependency is expected later in 2026 — worth checking on a future pass. No independent audit of Sierra itself, as opposed to its PCI certification, has been located. Re-checked again this pass: the Twilio-dependent voice path remains the live option, with no public confirmation yet that the carrier-agnostic version has shipped. No flag changes.