Stop mocking, start containerizing

“Write tests. Not too many. Mostly integration.” Kent C. Dods While unit tests have their place, integration tests validate how your systems behave under real-world conditions. Yet too often, developers fall back on mocks that simulate dependencies rather than testing with the actual services their code interacts with. In this workshop, we’ll explore a better approach: Testcontainers is a powerful Python library that enables you to run real Docker containers as part of your test suite. Whether you're testing against PostgreSQL, Redis, or HTTP APIs, you’ll learn how to spin up disposable, isolated environments that bring realism and confidence to your testing practice. Whether you're testing microservices, monolithic backends, or data pipelines, this workshop will show you how to build tests that don’t just pass but prove your system works. Bring your laptop and a running Docker engine, we’re going to get our hands dirty!