Quickstart

Take your first payment through Vermilion in about five minutes, entirely in the sandbox — no PSP account needed, no real money moved.

1 · Get your sandbox API key

Request sandbox access at hello@vermil.dev. You'll receive dashboard credentials; create a secret key under API keys. Keys are environment-scoped — sandbox keys start with sk_sandbox_ and can never touch live money.

2 · Create your first payment

Every mutating request needs an Idempotency-Key — retry with the same key and you'll get the original result back instead of a duplicate charge.

sim_card is the built-in test PSP. Amounts are integers in minor units (1000 = €10.00), and the last two digits script the outcome — 1000 captures,1005 declines with insufficient_funds. See test cards for the full matrix.

3 · Read the result

The attempts array is the routing story: which PSP was tried, in what order, and why. Retrieve any payment later with GET /v1/payments/:id.

4 · Hear about it via webhook

Register an endpoint and you'll receive normalized events (payment.captured,payment.failed, refund.succeeded…) for every PSP the same way:

The response contains the signing secret exactly once — verify every delivery with it as described in webhooks.

Next steps

• Payments — manual capture, voids, partial refunds.
• Routing — rules, PSP chains and automatic fallback.
• Tokens — store cards once, charge on any PSP.
• Connect real Stripe and Adyen test accounts from the dashboard when you're ready.