Invoices

Bill a customer for line items; they pay online from the invoice’s page.

Watenga computes the totals (tax and discounts included), numbers the invoice, emails it with a payment link and reminds the customer. Partial payments and offline payments you record are kept against the balance.

Keys and scopes

A secret key, or a restricted key with the invoices scope.

Create and send an invoice

unit_price is a decimal string; the invoice’s total, amount_due and payment_url come back computed.

typescript

const invoice = await watenga.invoices.create({
  title: 'October retainer',
  customer_name: 'Ada Buyer',
  customer_email: 'ada@example.com',
  currency: 'USD',
  line_items: [{ description: 'Design work', quantity: 10, unit_price: '45.00' }],
  due_date: '2026-11-15',
});
await watenga.invoices.send(invoice.id);

Follow payment

List by status (draft, sent, viewed, partial, paid, overdue, cancelled, void), remind, or void an invoice that should not be paid.

typescript

for await (const inv of watenga.invoices.listAll({ status: 'overdue' })) {
  await watenga.invoices.remind(inv.id);
}

Webhook events

Event	When
`invoicing.invoice.sent`	The invoice was emailed
`invoicing.invoice.partially-paid`	Part of the balance was paid
`invoicing.invoice.paid`	Paid in full
`invoicing.invoice.unpaid`	The due date passed with a balance
`invoicing.invoice.cancelled`	Voided or cancelled

Each event carries the object in data.object; verify the signature first (Webhooks).

Test it

Use a test secret key (sk_test_…): it never moves money. Pay with the test cards and wallet numbers, and receive the webhooks on your machine with watenga listen --forward-to http://localhost:3000/webhooks (CLI).

An overdue invoice without waiting: advance the test clock past its due date and run POST /v1/developer/sandbox/clock/tick.

Related: Quotations · Customers