Phixius
Phixius Technical Briefing
Published November 17, 2020
Supported by The Kauffman Foundation and Modern Treasury
Overview
George (Nacha) and Peter demo Phixius — Nacha\'s business-focused data-services network for financial institutions, fintechs, and payment networks. Where consumer open banking addresses account holders, Phixius addresses the payment-provider side: exchanging data (ACH account validation, electronic payment information, etc.) between Credentialed Service Providers (CSPs) before a payment hits the rail. Phixius is point-to-point — no centralized storage, no give-to-get model. It combines standardized Nacha APIs with a blockchain/shared-ledger layer used for authentication, audit trail, and rule enforcement. Each request uses an authentication token that is effectively the address of a smart contract between the requesting CSP and responding CSP for that specific purpose. The demo runs two exchange services: an ACH account validation (routing + account → valid/invalid for Nacha), and an Electronic Payment Information exchange where Care-Free Catering at High-Rise Bank subscribes to payment info for Best Spreads at Low-Rise Credit Union — replacing the PDF-form email loop with an authoritative API exchange. A smart-contract subscription fires a notification when Best Spreads adds Zelle to their profile, proving the ongoing-update pattern.
0:00 Introduction to Nacha and Phixius
George introduces Nacha as the governance body for the US ACH network. Phixius is Nacha's newer utility — a business-focused data-services network (not consumer open banking) that enables financial institutions, fintechs, and payment networks to exchange data related to electronic payments.
1:30 Point-to-point architecture — no central storage
Connected participants are payment providers (banks, fintechs, networks) — not end customers. Phixius does not move money and does not centrally store any exchanged data. It is a point-to-point network between Credentialed Service Providers (CSPs) using open APIs.
3:00 Standardized APIs over blockchain audit trail
Peter explains the tech: standardized Nacha APIs define "exchange services" (single or collection of APIs for a use case). Blockchain/shared-ledger functionality replaces centralized storage — used for auditability, trust, and enforcing rules across CSPs.
4:30 ACH Account Validation exchange service
The first demo: an ACH account-validation exchange service. A CSP submits a routing+account combination and the responding CSP confirms it's valid to accept Nacha requests — surfaced via a green toaster in the UI.
6:00 Smart-contract-based authentication tokens
Each request requires an authentication token that is effectively the address of a smart contract between the requesting and responding CSPs for that specific purpose — providing both access control and the audit trail for dispute resolution.
7:30 Electronic Payment Information exchange service
A second exchange service lets a buyer's bank (High-Rise) request payment info for a vendor (Best Spreads) whose financial institution is Low-Rise Credit Union — replacing the classic PDF-form email dance with a trusted API exchange.
8:30 Smart contract subscription — notify on profile change
When Care-Free Catering subscribes to Best Spreads' EPI, a smart contract notifies them any time the vendor's payment profile changes — demoed by adding Zelle as a new payment method and seeing the subscriber get an "action required" update.
Presented by Peter Tapling and George Throckmorton — Phixius
