Testing
Testing an application that bills, without reaching a payment provider.
Troubleshooting
Every exception the package throws, what it is protecting, and what to do about it.
Upgrading
What each release changes, and which changes need action before you deploy.
Migrating from Cashier
Moving an existing Cashier installation across without reissuing documents or losing history.
Migrating from your own billing code
Replacing hand-rolled billing, and the order that keeps money correct while you do it.
Selling works to consumers
What the package tells you about a purchase, so you can label it correctly — and what it deliberately leaves to you.
Mounting your own payment element
Why the package ships no front-end JavaScript, and the seam for when you need the card fields inline.
Payment accounts
Charge into the Mollie or Stripe account of each shop or merchant your application serves, with that account's own credential, test mode and profile, next to the install's own driver.
Billing through Shopify
Bill the merchants of an app the Shopify App Store sells through Shopify's own billing, with subscriptions the merchant approves and their state taken from Shopify's webhooks.