Developers

Getting started

Quickstart

Get your first integration live in minutes.

1. Create a Fundolar Central owner account.
2. Ask your platform admin to enable Developer SDK (Platform Settings → Payments).
3. Go to Sites → Add integration and choose SDK / custom app.
4. Copy your API key and signing secret from the integration details page.
5. Download the SDK and make your first authenticated request.

Your first request

const { FundolarClient } = require('./fundolar-sdk.js');

const client = new FundolarClient({
  baseUrl: 'https://app.fundolar.com',
  apiKey: process.env.FUNDOLAR_API_KEY,
  signingSecret: process.env.FUNDOLAR_SIGNING_SECRET,
});

const config = await client.getConfig();
console.log('Connected to', config.platform.name);

# Use the SDK for signing, or implement HMAC manually.
# See Authentication for the canonical string format.
curl https://app.fundolar.com/api/sdk

Accept your first payment

Create a checkout session and redirect the donor:

const session = await client.createCheckoutSession({
  amount: 25.00,
  currency: 'USD',
  title: 'Support our mission',
  success_url: 'https://yourapp.com/thank-you',
  cancel_url: 'https://yourapp.com/donate',
});

// Redirect donor to session.checkout_url

Getting started

Authentication

Learn how to authenticate your API requests.

Fundolar uses HMAC-SHA256 request signing. Each integration receives an API key (fk_live_…) and a signing secret. Include four headers on every request:

Canonical string

METHOD + "\n" + PATH + "\n" + TIMESTAMP + "\n" + NONCE + "\n" + SHA256(body)

signature = HMAC-SHA256(canonical, signing_secret)

Example request

const session = await client.createCheckoutSession({
  amount: 50,
  currency: 'USD',
  title: 'Donation',
  success_url: 'https://example.com/success',
  cancel_url: 'https://example.com/cancel',
});

// Use fundolar-sdk.js via Node, or implement signing in PHP:
$method = 'POST';
$path = '/api/sdk/checkout-sessions';
$timestamp = (string) time();
$nonce = bin2hex(random_bytes(10));
$body = json_encode(['amount' => 50, 'currency' => 'USD']);
$hash = hash('sha256', $body);
$canonical = "$method\n$path\n$timestamp\n$nonce\n$hash";
$signature = hash_hmac('sha256', $canonical, $signingSecret);

Integrations

WordPress plugin

Installation

1. Download from fundolar.com/plugin/fundolar.zip.
2. In WordPress: Plugins → Add New → Upload, then activate Fundolar.
3. In Central: Sites → Add integration → WordPress. Copy the Site key.
4. In WordPress: Fundolar → Settings → Payments, paste the Site key and connect.

Campaign shortcodes

[fundolar_campaign id="42" style="card"]

Connection flow

The plugin calls POST /api/plugin/activate with your Site key. Central returns an API key and signing secret stored encrypted in WordPress. All sync uses HMAC-authenticated requests to /api/plugin/*.

See Administrator documentation and the changelog for release notes.

Integrations

JavaScript SDK

Installation

curl -O https://app.fundolar.com/sdk/fundolar-sdk.js
# or
curl -O https://fundolar.com/assets/js/fundolar-sdk.js

Initialize the client

const { FundolarClient } = require('./fundolar-sdk.js');

const client = new FundolarClient({
  baseUrl: 'https://app.fundolar.com',
  apiKey: process.env.FUNDOLAR_API_KEY,
  signingSecret: process.env.FUNDOLAR_SIGNING_SECRET,
});

Available methods

CORS & allowed domains

Configure allowed domains in Central → Sites → your integration. Browser-origin requests require a matching Origin header and valid HMAC signatures.

Integrations

Payment links

Share hosted checkout pages without writing payment UI code.

No-code setup

1. Sign in to Fundolar Central → Payment links.
2. Create a link with title, amount mode, and currency.
3. Share: https://app.fundolar.com/p/{shortCode}

Create via SDK

const link = await client.createPaymentLink({
  title: 'Event ticket',
  amount_mode: 'fixed',
  fixed_amount: 49.99,
  default_currency: 'USD',
  link_type: 'payment',
});

console.log(link.url); // https://app.fundolar.com/p/…

Amount modes

• open — donor chooses the amount on the hosted page.
• fixed — preset amount for tickets and product payments.

Integrations

Hosted checkout

Redirect donors to a Fundolar-hosted payment page from your app or website.

How it works

1. Your server calls POST /api/sdk/checkout-sessions.
2. Fundolar creates a pending donation and returns checkout_url.
3. Redirect the donor to the hosted page.
4. After payment, donor returns to your success_url.
5. Poll GET /api/sdk/donations/{id}/status or rely on the redirect query params.

Full example

const session = await client.createCheckoutSession({
  amount: 25.00,
  currency: 'USD',
  title: 'Monthly support',
  donor_name: 'Jane Doe',
  donor_email: 'jane@example.com',
  success_url: 'https://yourapp.com/thank-you',
  cancel_url: 'https://yourapp.com/donate',
  idempotency_key: 'donation-' + Date.now(),
});

res.redirect(session.checkout_url);

{
  "donation_id": 123,
  "uuid": "a1b2c3d4-…",
  "checkout_url": "https://app.fundolar.com/sdk/checkout/…",
  "expires_at": "2026-06-09T14:00:00+00:00",
  "status": "pending"
}

API Reference

API overview

Base URL: https://app.fundolar.com · SDK namespace: /api/sdk/*

Discover available endpoints:

GET https://app.fundolar.com/api/sdk

Errors

JSON responses include a message field. Common codes:

WordPress sites also use /api/plugin/* with the same HMAC scheme — the plugin handles signing automatically.

API Reference

Donations API

Create, update, and query donation records.

Request body

{
  "gross_amount": 100,
  "currency": "USD",
  "donor_name": "Jane Doe",
  "donor_email": "jane@example.com",
  "payment_gateway": "stripe",
  "source_channel": "sdk",
  "idempotency_key": "order-2026-001"
}

API Reference

Payment links API

Programmatically create and manage hosted payment links.

API Reference

Checkout sessions API

Create time-limited hosted checkout URLs.

Parameters