Billing
FeatureSignals supports PayU and Stripe as payment gateways for subscription management. Organizations can switch between gateways via the Update Gateway endpoint.
Pricing
Retrieve the canonical pricing configuration. This is a public endpoint — no authentication required.
GET /v1/pricing
Response 200 OK
{
"currency": "INR",
"currency_symbol": "₹",
"plans": {
"free": {
"name": "Free",
"price": 0,
"display_price": "₹0",
"billing_period": "month",
"limits": { "projects": 1, "environments": 2, "seats": 3 },
"features": ["1 project", "2 environments per project", "..."]
},
"pro": {
"name": "Pro",
"price": 999,
"display_price": "INR 1,999",
"billing_period": "month",
"limits": { "projects": -1, "environments": -1, "seats": -1 },
"features": ["Unlimited projects", "Unlimited environments", "..."]
},
"enterprise": {
"name": "Enterprise",
"price": null,
"display_price": "Custom",
"features": ["Everything in Pro", "Dedicated support", "..."]
}
}
}
Create Checkout
Initiate a payment session for upgrading to the Pro plan. The response varies depending on the org's configured gateway (PayU or Stripe).
POST /v1/billing/checkout
Authentication: Bearer JWT
Query Parameters
| Param | Type | Required | Description |
|---|---|---|---|
return_url | string | No | Flag Engine path to redirect after payment. Allowed: /settings/billing, /onboarding |
Response 200 OK
The response includes a gateway field indicating which payment provider is being used, along with gateway-specific fields.
Stripe — returns a redirect_url for the Stripe Checkout session:
{
"gateway": "stripe",
"redirect_url": "https://checkout.stripe.com/c/pay/..."
}
PayU — returns form fields that the frontend must POST to the payu_url:
{
"gateway": "payu",
"payu_url": "https://secure.payu.in/_payment",
"key": "merchant_key",
"txnid": "FS_abc12345_1711929600000",
"hash": "sha512_hash_string",
"amount": "1999.00",
"productinfo": "FeatureSignals Pro Plan",
"firstname": "Jane",
"email": "jane@company.com",
"phone": "9999999999",
"surl": "https://api.featuresignals.com/v1/billing/payu/callback",
"furl": "https://api.featuresignals.com/v1/billing/payu/failure"
}
PayU Callback (Success)
Handles PayU's server-to-server callback after successful payment.
POST /v1/billing/payu/callback
This endpoint:
- Verifies the PayU hash signature
- Creates or updates the organization's subscription to
pro/active - Redirects to the Flag Engine billing page with
?status=success
PayU Failure
Handles PayU's redirect after failed payment.
POST /v1/billing/payu/failure
Redirects to the Flag Engine with ?status=failed.
Stripe Webhook
Handles incoming Stripe webhook events for subscription lifecycle management.
POST /v1/billing/stripe/webhook
Verified via the Stripe-Signature header. Processes the following event types:
| Event | Action |
|---|---|
checkout.session.completed | Upgrades org to Pro, creates subscription |
customer.subscription.updated | Updates subscription status |
customer.subscription.deleted | Cancels subscription, downgrades org to Free |
invoice.payment_failed | Marks subscription as past_due, notifies admins |
Duplicate events are handled idempotently via the gateway event ID.
Get Subscription
Retrieve the current organization's subscription and plan details.
GET /v1/billing/subscription
Authentication: Bearer JWT
Response 200 OK
{
"plan": "pro",
"seats_limit": -1,
"projects_limit": -1,
"environments_limit": -1,
"gateway": "stripe",
"status": "active",
"current_period_start": "2026-04-01T00:00:00Z",
"current_period_end": "2026-05-01T00:00:00Z",
"cancel_at_period_end": false,
"can_manage": true,
"seats_used": 2,
"projects_used": 1
}
| Field | Description |
|---|---|
status | active, past_due, canceled, or none |
cancel_at_period_end | If true, access continues until current_period_end |
can_manage | true for Stripe subscriptions (portal access available) |
gateway | payu or stripe |
A limit value of -1 means unlimited (Pro/Enterprise).
Get Usage
Retrieve current resource usage against plan limits.
GET /v1/billing/usage
Authentication: Bearer JWT
Response 200 OK
{
"seats_used": 2,
"seats_limit": 3,
"projects_used": 1,
"projects_limit": 1,
"environments_used": 2,
"environments_limit": 2,
"plan": "free"
}
A limit value of -1 means unlimited (Pro/Enterprise).
Cancel Subscription
Cancel the org's active subscription.
POST /v1/billing/cancel
Authentication: Bearer JWT
Request
{
"at_period_end": true
}
| Field | Type | Required | Description |
|---|---|---|---|
at_period_end | boolean | No | If true (default), access continues until the current billing period ends. If false, cancels immediately and downgrades to Free. |
Response 200 OK
{
"status": "canceled"
}
Error 400 Bad Request
PayU subscriptions cannot be canceled through the API — contact support.
Error 404 Not Found
No active subscription exists for the organization.
Billing Portal
Get a URL for the Stripe customer billing portal where users can manage payment methods, view invoices, and update billing details.
POST /v1/billing/portal
Authentication: Bearer JWT
Response 200 OK
{
"url": "https://billing.stripe.com/p/session/..."
}
Error 400 Bad Request
Returned if the subscription is not managed by Stripe.
Error 404 Not Found
No active subscription exists for the organization.
Update Gateway
Change the organization's configured payment gateway.
PUT /v1/billing/gateway
Authentication: Bearer JWT
Request
{
"gateway": "stripe"
}
| Field | Type | Required | Description |
|---|---|---|---|
gateway | string | Yes | payu or stripe |
Response 200 OK
{
"gateway": "stripe"
}
Error 400 Bad Request
Returned if the gateway name is not supported.