Idempotency: Why Retrying a Payment Is Safe
Imagine a customer clicks Pay, their connection drops, and they click again unsure whether it worked. Without safeguards they could be charged twice. Idempotency is the principle that prevents this.
It means an action can be safely repeated and still only happen once — essential for payments, orders and anything where a duplicate would be costly.
How It Works in Practice
Each sensitive request carries a unique key. The first time the server sees that key it does the work; if the same key arrives again, it simply returns the original result instead of repeating the action.
- No double charges on a flaky connection.
- Safe automatic retries when a network call times out.
- Confidence that webhooks processed twice cause no harm.
Where We Apply It
Payments are the obvious case, but we use the same idea for placing orders, sending notifications and any operation a client might reasonably retry.
Frequently Asked Questions
Does this slow down the checkout?
Not noticeably. The check is a quick lookup that adds safety without any meaningful delay.
If you need a hand with any of this, your Progressive Robot delivery team is ready to help. Raise a ticket from the Support area of your client portal or speak to your account manager and we will guide you through the next steps.