FYATU CaaS API v3.20

The FYATU Cards-as-a-Service (CaaS) API v3.20 lets you issue virtual Visa and Mastercard prepaid cards to your users at scale, directly from your server. No card industry experience required — you bring the users, we handle the card rails, compliance, and settlement.

What You Can Build

Cardholder Management

Create cardholder profiles, trigger KYC, suspend fraudulent users, and reactivate them — all via API.

Card Issuance

Issue virtual cards in seconds. Fund, freeze, unfreeze, or terminate any card on demand.

Transaction Monitoring

Query real-time card transactions with merchant data, MCC codes, and authorization status.

Webhook Events

Subscribe to 30+ event types — from TRANSACTION_PROCESSED to CARDHOLDER_KYC_APPROVED — and react in real time.

How It Works

Your Platform                    FYATU CaaS API
─────────────────────────────────────────────────

1. Create cardholder             POST /cardholders
   (KYC triggered automatically)

2. Wait for KYC approval         CARDHOLDER_KYC_APPROVED webhook

3. Issue card                    POST /cards
   (zero balance, ready to fund)

4. Fund card                     POST /cards/{id}/fund
   (debits your program ledger)

5. Cardholder transacts          TRANSACTION_PROCESSED webhook
   (real-time Visa/Mastercard)

6. Unload or terminate           POST /cards/{id}/unload
   when done                     POST /cards/{id}/terminate

Key Concepts

API Keys

Authentication is done via API keys. Each key is bound to one environment (LIVE or SANDBOX) and carries specific scopes that control what the key can do. Create and manage keys in the CaaS portal. See Authentication.

Environments

SANDBOX — no real money, no real cards. Perfect for development and QA. KYC completes in seconds and card issuance is instant.
LIVE — real card issuance, real transactions. Use only when your integration is fully tested.

Environments are fully isolated. A SANDBOX API key cannot read or write LIVE data and vice versa.

Card Programs

Every cardholder and card belongs to a card program — a container you configure in the portal that sets the card network (Visa/Mastercard), currency, spending limits, and compliance rules. The API references programs by programId.

Cardholders

A cardholder is the end-user who will hold and spend on a card. Cardholders must complete KYC (Know Your Customer) identity verification before a card can be issued to them. The kycStatus field tracks progress: PENDING → APPROVED (or REJECTED).

The Program Ledger

Your program holds a pre-funded balance — the “program ledger” — that funds are drawn from when you load a card. When you call POST /cards/{id}/fund, money moves from the program ledger to the card. When you call POST /cards/{id}/unload or a card is terminated, the balance returns to the ledger. Monitor and top up your program balance in the portal.

Response Envelope

Every API response uses a consistent shape:

Single resource

{
  "success": true,
  "status": 200,
  "message": "Cardholder retrieved",
  "data": { ... },
  "meta": {
    "requestId": "req_01HXY123456ABCDEF",
    "platform": "Fyatu CaaS",
    "timestamp": "2026-05-22T10:00:00Z"
  }
}

Paginated list

{
  "success": true,
  "status": 200,
  "message": "Cardholders retrieved",
  "data": [ ... ],
  "pagination": {
    "total": 47,
    "limit": 20,
    "offset": 0,
    "hasMore": true
  },
  "meta": {
    "requestId": "req_01HXY123456ABCDEF",
    "platform": "Fyatu CaaS",
    "timestamp": "2026-05-22T10:00:00Z"
  }
}

See Error Handling for the full envelope specification and all error codes.

Base URL

All v3.20 requests go to:

https://api.fyatu.com/api/v3.20

API Surface

Resource	Endpoints	Scopes
Cardholders	Create, List, Get, Update, Suspend, Reactivate	`cardholders:read`, `cardholders:write`
Cards	Issue, List, Get, Fund, Unload, Freeze, Unfreeze, Terminate	`cards:read`, `cards:write`
Transactions	List, Get	`transactions:read`
Webhooks	Create, List, Get, Update, Delete	`webhooks:read`, `webhooks:write`

Next Steps

Read the authentication guide

Learn how to create an API key, set its scopes, and send it with requests. Authentication →

Follow the quickstart

Create your first cardholder, wait for KYC, issue a card, and fund it in under 5 minutes. Quickstart →

Set up webhooks

Subscribe to events so your platform reacts in real time — no polling needed. Webhook Guide →

Getting Started

Concepts

Introduction

FYATU CaaS API v3.20

What You Can Build

Cardholder Management

Card Issuance

Transaction Monitoring

Webhook Events

How It Works

Key Concepts

API Keys

Environments

Card Programs

Cardholders

The Program Ledger

Response Envelope

Base URL

API Surface

Next Steps

​FYATU CaaS API v3.20

​What You Can Build

Cardholder Management

Card Issuance

Transaction Monitoring

Webhook Events

​How It Works

​Key Concepts

​API Keys

​Environments

​Card Programs

​Cardholders

​The Program Ledger

​Response Envelope

​Base URL

​API Surface

​Next Steps

FYATU CaaS API v3.20

What You Can Build

How It Works

Key Concepts

API Keys

Environments

Card Programs

Cardholders

The Program Ledger

Response Envelope

Base URL

API Surface

Next Steps