Developers

SDKs

Official libraries for Node.js / TypeScript, PHP and Python. Same resources, same behaviour, same safety guarantees.

Language	Package	Requires
TypeScript / JavaScript	`@muny/sdk`	Node 18+, Bun, Deno, edge runtimes
PHP	`muny/muny-php`	PHP 8.1+, ext-curl, ext-json
Python	`muny`	Python 3.9+

All three have zero runtime dependencies and share the same design:

Idempotency built in. Creating a payment intent, checkout session, payout or payout batch always sends an Idempotency-Key and reuses it on retries, so a network blip never charges or pays twice. Pass your own key (your order id) to make your own retries safe too.
Retries with exponential backoff and jitter on connection errors, 429 (honouring Retry-After) and 5xx — only for safe or idempotent requests.
Typed errors carrying status, type, code, request id and details: authentication, permission, not found, invalid request, idempotency, conflict, risk, rate limit, API and connection errors.
Money is always a string. Amounts are decimal strings; the Python SDK rejects floats outright.
Webhook verification with constant-time comparison and a 5-minute replay window.

Node.js / TypeScript#

bash

npm install @muny/sdk

server.ts

import { Muny } from "@muny/sdk";

const muny = new Muny({ apiKey: process.env.MUNY_API_KEY });

const payment = await muny.paymentIntents.create({
  display_amount: "29.00",          // price in your currency…
  display_currency: "USD",          // …Muny quotes the MUNY amount
  reference: "ORDER-48291",
  success_url: "https://shop.example/thanks",
});

redirect(payment.checkout_url);

Secret keys are server-side only — the SDK refuses to run with an apiKey in a browser. Create the payment on your server and redirect the customer to checkout_url.

PHP#

bash

composer require muny/muny-php

checkout.php

$muny = new \Muny\MunyClient(['api_key' => getenv('MUNY_API_KEY')]);

$payment = $muny->paymentIntents->create([
    'display_amount'   => '29.00',
    'display_currency' => 'USD',
    'reference'        => 'ORDER-48291',
    'success_url'      => 'https://shop.example/thanks',
]);

header('Location: ' . $payment->checkout_url);

Python#

bash

pip install muny

app.py

import os, muny

client = muny.Muny(api_key=os.environ["MUNY_API_KEY"])

payment = client.payment_intents.create(
    display_amount="29.00",
    display_currency="USD",
    reference="ORDER-48291",
    success_url="https://shop.example/thanks",
)

return redirect(payment.checkout_url)

Verify webhooks#

Always verify against the raw request body, before parsing JSON, and fulfil orders on payment.confirmed — never on the customer's redirect. See payment webhooks.

text

// Node
const event = await verifyWebhook(rawBody, req.header("muny-signature"), secret);

// PHP
$event = \Muny\Webhook::constructEvent($payload, $_SERVER['HTTP_MUNY_SIGNATURE'] ?? null, $secret);

# Python
event = muny.Webhook.construct_event(request.get_data(), request.headers.get("Muny-Signature"), secret)

Send payouts#

The same clients send payouts from the balance your payments settle into.

text

// Node
await muny.payouts.create({ recipient: "7xKX…gAsU", amount: "500", reference: "affiliate-123" });

// PHP
$muny->payouts->create(['recipient' => '7xKX…gAsU', 'amount' => '500', 'reference' => 'affiliate-123']);

# Python
client.payouts.create(recipient="7xKX…gAsU", amount="500", reference="affiliate-123")

Test and live

mk_test_… keys run against Muny's devnet environment, mk_live_… keys against mainnet. Every SDK takes a base_url / baseUrl option if you use a staging or self-hosted API.

Selling on WordPress?

The Muny for WooCommerce plugin is built on the PHP SDK — no code required.