SaaS and software operations
How to design a reliable payment verification workflow
A payment is only confirmed when verified against the provider. This outline shows the steps that make that reliable.
Never trust the browser
A redirect back to your site, a client-side callback, or a success message in the interface is not proof of payment. Treat the provider's verified notification as the source of truth.
Verify signatures on the raw payload
Validate the provider's webhook signature using the exact received bytes and your server-side secret. Reject invalid or missing signatures.
Make processing idempotent
Store provider event identifiers and enforce uniqueness so duplicated deliveries cannot create duplicate payments, invoices, or entitlements.
Model pending and failed states
Represent initiated, pending, failed, and verified separately. Only a verified state should activate paid access.
Reconcile periodically
Compare internal records with provider evidence on a schedule, and investigate mismatches rather than adjusting records to make totals agree.