Brute Force Correctness

Session description

So you’re a maintainer of a GraphQL system. Whether it’s a federation gateway, a complex client library, or a custom executor—how do you know that it’s capital-C Correct? Your tests are decent, and they seem to pass, but what about the test cases that you didn’t think of? Did you remember to handle @skip directives on fragment spreads? What about when those directives use variables? Or when you spread an abstract type in an abstract scope? Would you trust your system to serve million-dollar transactions? This session will cover how probabilistic testing can be applied to complex GraphQL systems to find bugs in places we wouldn’t have thought to look. We’ll discuss how Airbnb leveraged this approach to launch a novel GraphQL engine with 0 spec conformance bugs, and how you can apply these same techniques to build unshakable confidence in your own systems.