Create a customer in Square when a payment fails in Stripe

When a payment fails in Stripe, create a customer in Square.

Start the 14-day trial, then find it under Templates → Library. It installs into the client you choose, switched off, with its checklist.

UsesBeta

Every step, in order

When it happens in the first app, the step runs in the second, with the client’s own account.

A payment fails: A Stripe invoice payment attempt declined, or no card on file, within seconds. Once per attempt: Smart Retries can fire it again for the same invoice. The restricted key needs Webhook Endpoints: write.
Create a customer: A new customer in the client’s Square directory.

Nothing. It needs only the accounts it connects to.

Each is the client’s own, stored encrypted and never copied between clients. Until one is added the client’s checklist shows it, and nothing runs.

In the client’s Stripe dashboard: Developers → API keys → Create restricted key. Give it only what the steps need: Customers write, Payment Links write, Prices read, Invoices write, and Webhook Endpoints write for the triggers. Leave “IP access” empty: Thrum has no fixed addresses, so a key locked to IPs fails every call.
Square
developer.squareup.com → the client’s application (their own account) → Credentials → Production access token. A personal access token for the client’s own account needs no Square review.