North Bay Python 2024

Hypothesis Levels Up: codegen, observability, fault localization, and a black-magic backend
2024-06-29, 13:40–14:05 (US/Pacific), Barn

You might have heard of Hypothesis - a testing library which has been generating test inputs and finding bugs for eleven years now, and used by about 5% of all Python users (Pytest is about 50%). But have you seen the more advanced tricks?

  • GASP as hypothesis write generates the tests themselves! (without a language model)
  • THRILL at our new observability tooling - you'll never wonder what happened again!
  • BRACE YOURSELF for a workflow with coverage-guided evolution, the black art of SMT solving, and a distributed database!

Come one, come all, and enjoy a live demo that you won't soon forget! With a little luck, you might even find something practical to take away for your own testing....

Zac grew up in Australia eating dark chocolate, reading books, and occasionally indulging in both at the same time. By day he works at Anthropic, an AI safety and research company in San Francisco; by night he (co-) maintains Hypothesis and Pytest, and contributes to a range of other Python projects. You can read more about him at