🧪 Do you really enjoy writing tests with mocks?
Or maybe...

➡️ You had a bug in production even though everything was tested?
➡️ You have to change the test when you refactor?
➡️ You’re sometimes lost in mock setups?
➡️ Integration with external services is source of bugs?

What if the real problem... were the mocks themselves? 👀
Johan Martinson and Mathieu Cans are proposing a simpler, more reliable alternative based on their experience:
🎭 Simulators instead of mocks, validated by Adapter Contract Testing at architecture hexagonal boundaries.

💡 The idea?
- hand-code a simulator that behaves like the real service or database.
- write integration test against the real service — that’s our contract.
- use same test to validate the simulator.

Result: No more trouble 😉🇯🇲👇🏽
✅ Robust, expressive, business-focused tests that stay close to reality.
🚫 No more production surprises because of a badly tuned mock.
🚫 No more incomprehensible tests.
🚫 No more unexpected behavior from dependencies.

• Solid understanding of unit testing
• Participants will use their own laptop with Docker working and Either TypeScript+Node, Java or Python
• Knowledge of TDD and hexagonal architecture can be helpful
• Clone https://github.com/adapter-contract-testing/snail-race-kata and follow the requirements in the README of the chosen language.