Real examples from teams working with complex integrations. We've spent years testing APIs across banking systems, e-commerce platforms, and logistics networks throughout Southeast Asia.
We started documenting these patterns back in early 2024 when a Bangkok logistics company needed help with their delivery tracking system. Their API returned inconsistent responses during peak hours, and we had to figure out why.
View examples →Payment webhooks can be tricky. Last month, we worked with an online marketplace that was losing transaction notifications. Turns out their retry logic wasn't handling 202 responses correctly.
Read more →OAuth2 implementations vary wildly between providers. We've tested dozens of authentication flows and documented the edge cases that actually matter when your tokens expire at 3 AM.
Explore patterns →These aren't theoretical examples. Each guide comes from actual projects where something broke, and we had to fix it.
A tourism booking platform in Chiang Mai was accepting malformed JSON from their hotel partners. Customers would complete bookings, but reservations never reached the properties.
We built validation rules that caught schema mismatches before they hit production. Now they test every partner integration against the same contract.
{ "booking_id": "TH-2025-47832", "status": "confirmed",
"check_in": "2025-06-15", "guest_count": 2 }
When you're processing thousands of transactions per hour, rate limits become real problems fast. We learned this working with a food delivery service during their Songkran promotion.
Their third-party payment API started throttling requests at 500/minute. No warning in their documentation. Just sudden 429 errors when lunch rush hit.
So we documented how to test rate limits properly, including retry strategies that actually work when APIs behave unpredictably.
This is how we approach API testing projects. Each step comes from patterns that proved reliable across different industries.
Start by understanding what's actually talking to what. We worked with a retail chain that thought they had 12 API connections. When we mapped everything, we found 37 active integrations nobody had documented.
Draw diagrams. List every endpoint. Note which services depend on which responses. It's boring work, but you can't test what you don't understand.
Happy path testing is easy. Everything works until it doesn't. What happens when the payment gateway returns a timeout? When inventory data is stale? When the customer service API goes down during a flash sale?
We create scenarios based on real failures we've seen. Network timeouts. Malformed responses. Rate limiting. Authentication failures. Each one gets a test case.
Testing isn't one-and-done. APIs change. New endpoints get added. Old ones get deprecated without warning. We set up monitoring for a client in February 2025, and it caught three breaking changes in the first month.
Pro tip: Version your API contracts and test against each version separately. When partners upgrade their APIs, you'll know exactly what broke.