Payments

Prime abstracts payment processing behind a gateway factory — you configure one gateway and the entire codebase works the same regardless of provider.

Active gateway

Set in demo-server/.env:

PAYMENT_GATEWAY=lemonsqueezy   # or stripe

See Lemon Squeezy Setup and Subscriptions for full configuration.

Payment flow

User clicks Upgrade
  → POST /checkout-link  (creates session with gateway)
  → User redirected to hosted checkout page
  → User completes payment
  → Gateway fires webhook → POST /webhooks/lemonsqueezy (or /stripe)
  → Account upgraded, subscription IDs stored

The checkout response is returned flat (not wrapped in data): { checkoutUrl, expiresAt, sessionId, clientToken, plan, gateway, interval }.

Accounts that already have an active subscription change plans with POST /account/upgrade instead — see Subscriptions for the upgrade flow.

API endpoints

Method	Endpoint	Description
GET	/payments	List payment history for the account
GET	/invoices	List invoices (paginated with limit/offset)
POST	/checkout-link	Generate a checkout URL (body: { plan_id })
GET	/subscription/status	Get the account's current subscription status
POST	/subscription/cancel	Cancel the subscription
POST	/subscription/resume	Undo a scheduled cancellation
GET	/subscription/portal-url	Get the gateway's hosted billing portal URL
POST	/account/upgrade	Switch to a different plan on an active subscription

Master payment endpoints

Method	Endpoint	Description
GET	/master/payments	View all payment records across all accounts

Supported gateways

Gateway	Monthly	Webhooks
Lemon Squeezy	✓	✓
Stripe	✓	✓

Each gateway is implemented as a class in demo-server/services/paymentGateways/ extending BaseGateway, with a common interface covering checkout, cancel, resume, changePlan, portal, invoices and webhook parsing. Switching is a one-line env var change plus that gateway's price IDs and webhook registration.

See Lemon Squeezy Setup for the current Stripe caveats before enabling it in production.