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Build wallet-based payments with FEX

Accept payments across POS, web, and mobile using QR flows, wallet approvals, refunds, and real-time webhooks.

What is FEX?

FEX is an alternative payment method that lets customers pay directly from funded wallet balances, without relying on traditional card rails.

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Start here

1

Get your credentials

Receive your merchant_id, client_id, and client_secret from your platform administrator and store them securely.
2

Generate an access token

Authenticate using the OAuth2 client credentials flow before calling any merchant API.
3

Create your first payment

Start with the Standard QR flow to create a payment intent and display a QR code to the customer.
4

Handle payment confirmation

Verify incoming webhooks and mark orders as paid when you receive payment.completed.

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Payment flows

Standard QR

Create a payment intent, display a QR code, and let the customer confirm in their wallet app.

Reverse QR

Scan the customer’s wallet QR at the counter and trigger an approval request.

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Integration guides

Overview

Learn the two supported payment flows and choose the right checkout experience.

Getting Your Credentials

Set up merchant credentials and store secrets securely.

Generating an Access Token

Authenticate with OAuth2 and implement safe token refresh logic.

Standard QR Flow

Build the merchant-initiated QR flow end to end.

Reverse QR Flow

Build the counter-scan flow where the customer presents their wallet QR.

Webhooks

Verify signatures and handle payment lifecycle events reliably.

Cancellations & Refunds

Cancel pending intents and refund completed payments.

Transaction History

Retrieve paginated merchant transaction history for reporting and reconciliation.

Counter Management

Register terminals, manage counters, and rotate webhook secrets.

Error Reference

Understand common API errors and recommended retry behavior.

Quick-Start Checklist

Validate your setup before going live.

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What you can build

POS payments

Use merchant-generated QR or reverse QR for in-person checkout at the counter.

Web checkout

Display QR on desktop checkout and let customers approve on mobile.

Mobile experiences

Extend wallet-based payments into app and mobile commerce flows.

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Platform highlights

  • Wallet-based payments for direct, card-free transactions
  • POS and ecommerce support across in-person and online flows
  • Real-time webhooks for payment lifecycle events
  • Refund workflows for post-payment operations
  • Secure authentication using OAuth2 and signed webhook delivery

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Core concepts

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Wallets

Customers fund their FEX wallet using supported bank transfer or cash-based funding methods, then use those balances to pay merchants.

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Allocations

FEX uses an allocation model to organize funds into spending buckets. Allocations can include constraints such as merchant restrictions or expiration dates, and eligible payments draw from the most restrictive allocation first.

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Build confidently

Use the guides in this portal to:
  • authenticate securely
  • create payment intents
  • display QR codes
  • receive confirmation via webhook
  • manage transactions and refunds

Ready to integrate?

Start with credentials setup and launch your first FEX payment flow.