Designing resilience for third-party integrations.

Designing resilience for third-party integrations.

When you're building a system where your core business logic relies on third-party services, it can be stressful and dicey. You don’t have control over their downtime or failures.
But the good news is that you can mitigate this risk by using a FAILOVER LOGIC strategy.

In simple terms:
You can have multiple providers for the same service, and design your system to rank them based on their success rate. When a request comes in, your system starts with the most reliable provider. If it fails, it automatically switches to the next one and continues until it gets a successful response.
While this sounds beautiful, the caveat is that it can increase your latency, since it waits for one provider to fail before trying the next.

A smarter approach? Use PARALLEL PROCESSING, call all the providers at once, and use the first one that returns a success response.
Now, what if the providers charge per API call? That makes parallel calls more expensive.

In that case, go with the first (sequential) method, just make sure you reduce the timeout for each provider, so failures are detected quickly and you can move on fast.

As always, it’s a tradeoff between speed, cost, and reliability. You just have to choose what works best for you.