Developers

Connect your product to billing

Three APIs, one set of permissions. Every key acts as a real user and only sees what that user can see.

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APIs

REST

Customers, subscriptions, plans, invoices, usage and access checks, with an OpenAPI description.

OData v4

Connect Excel and Power BI directly to live billing data.

GraphQL

Ask for exactly the fields you need in one request.

Secure by design

Personal API keys

Scoped, expiring and IP-restricted. Stored hashed, shown once.

Rate limits and audit

Every call is limited and logged.

Idempotency

Retry safely without creating duplicates.

Webhooks

Signed events

Timestamped HMAC-SHA256 signatures you can verify.

Retries

Automatic backoff when your endpoint is down.

Zapier, Make and Slack

Plug events into the tools you already use.

Scopes

Read

customers:read, subscriptions:read, invoices:read, reports:read

Write

customers:write, subscriptions:write, usage:write

Access checks

access:read for checking member access from your app

Code examples

Create a customer · bash

curl https://billcaster.com/api/public/v1/customers \
  -H "Authorization: Bearer bcp_..." \
  -H "Idempotency-Key: 7f3c..." \
  -d '{"name":"Acme ApS","email":"billing@acme.dk","country":"DK"}'

Verify a webhook · js

const [t, sig] = parse(req.headers["billcaster-signature"]);
const expected = hmacSha256(secret, `${t}.${rawBody}`);
if (!timingSafeEqual(sig, expected)) throw new Error("Bad signature");