> ## Documentation Index
> Fetch the complete documentation index at: https://docs.cast.digitalfinancehq.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Why Confirm & Pay is our first product

> Why accounts payable is the first deployable proof of the architecture.

The CAST architecture is vertical-agnostic. **Confirm & Pay** — the accounts-payable instantiation — is where we prove it. AP is not a niche; it is the cleanest place to demonstrate the bilateral event loop and capture the first units of proof.

<Card title="See Confirm & Pay in action" icon="arrow-up-right-from-square" href="https://cast.digitalfinancehq.com">
  How it works, the covered controls, and the interactive walk-through live on the main site. Request a demo there.
</Card>

## Four reasons AP goes first

<CardGroup cols={2}>
  <Card title="The damage is concentrated" icon="bullseye">
    First payment to a new vendor, a bank-account change, a rush payment, a threshold breach — a handful of triggers account for most unilateral-instruction fraud. We start exactly where the risk lives.
  </Card>

  <Card title="The loop is provable in one screen" icon="rotate">
    Propose → confirm → release is the entire architectural claim, demonstrable end-to-end without downstream GL automation.
  </Card>

  <Card title="The vendor adopts nothing" icon="link-slash">
    The counterparty is a signer, not a tenant — a browser link, three actions, no app, no account. Adoption friction is near zero.
  </Card>

  <Card title="Every other vertical is configuration" icon="sliders">
    The same architecture extends to other verticals — association and HOA payments, GPU compute financing, and institutional grant disbursement — with different event types and policies, not a re-architecture.
  </Card>
</CardGroup>

## What the buyer evaluates

<Note>
  The case for AP first rests on four things a CFO already recognizes: an **acute problem** (\$2.9B in annual U.S. BEC losses), **measurable ROI** (reconciliation from days to minutes), an **existing budget** (AP controls and fraud prevention are funded line items), and a **foundation** for broader CAST adoption.
</Note>

## How it sits with your existing systems

CAST sits alongside your ERP — not in place of it — and produces posting-ready exports with the lineage hash in the memo field. Confirm & Pay is a pre-release control: covered payments remain held until the vendor confirms the terms or an exception is reviewed. It does not replace the ERP, create seller-side ledgers, or require vendors to adopt a new system.

<Card title="What CAST is not" icon="circle-xmark" href="/start-here/what-cast-is-not">
  The boundaries, stated plainly.
</Card>