Building concurrent apps is never easy. And when it is to do with payments, complexity and the stakes rises massively. We have designed and built a universal payment sandbox (maybe better to be called an omni-sandbox) which tech teams can use for the integration work, ongoing QA and CI workflows. And on top of this, allowing teams to load test their payment channels for real. No more shortcuts, real metrics on how your software works under load, with an important 3rd party (mock) dependency.
With the talk, we'd wish to present the system we've designed and built with a mix of Erlang and Elixir. The system is designed to handle surge of traffic (for load testing) and accurately simulate everyday payment scenarios.