Test keys now.
Live keys once a card is on file.

1. 1
   Sign up

   Your test client_id, client_secret and customer_id come back in this one response.
2. 2
   Point your code at staging

   Change the token URL and the API base; keep every request and handler as it is.
3. 3
   Test end to end

   Set a webhook URL, create a delivery with a simulated courier, watch every event and request in the logs.
4. 4
   Go live

   Add a card in Billing, take live keys, switch the two hosts to production.