✨This talk was recorded at Lambda Days 2023. If you're curious about our upcoming event, check https://lambdadays.org ✨ Have you ever tried testing that your system fairly delivers requests to worker threads or that updates eventually reach all your nodes? These are “liveness properties” and testing them is hard work! Wouldn’t it be great if you could say roughly what your system does and what it takes for the property to hold and have the computer come up with the tests? Fortunately, QuickCheck Dynamic gives you this power! At Quviq we’ve been successfully using property-based testing since 2006 and in this talk I’m going to tell you about our recent open source extension to Haskell QuickCheck that makes it easy to test even the trickiest properties. The work I will present puts together established techniques that have previously only been available in papers and new ideas that let you give strategies for reaching the most difficult-to-test behaviours in your system. In the talk I will highlight both the principles behind and successful use cases of QuickCheck Dynamic. Let's keep in touch! Follow us on: 💥Twitter: https://twitter.com/LambdaDays 💥LinkedIn: https://www.linkedin.com/company/lambda-days 💥Facebook: https://www.facebook.com/lambdadays 💥Mastodon: https://genserver.social/codesync