"✨This talk was recorded at Code BEAM Europe 2023. If you're curious about our upcoming event, check https://codebeameurope.com ✨ Abstract: Erlang’s type language provides powerful such as parametric polymorphism, equi-recursive types, as well as singleton, union, and (a variant of) intersection types. But its type signatures mainly serve as documentation as language features such as pattern matching and dynamic type tests complicate the design of a static type system. In our talk, we present etylizer, a static type checker for Erlang that adopts set-theoretic types as its foundation. With a demo on selected case studies, we will demonstrate how existing Erlang code can be statically typechecked without or with only minor modifications to the code. We will further show how set-theoretic types can enhance the development process and improve code quality for idiomatic Erlang code. The etylizer project is funded by the Erlang Ecosystem Foundation and developed as free open-source software here: https://github.com/etylizer/ Let's keep in touch! Follow us on: 💥 Twitter: https://twitter.com/CodeBEAMio 💥 Facebook: https://www.facebook.com/CodeSyncGlobal 💥 Linkedin: https://www.linkedin.com/company/code-sync 💥 Mastodon: https://genserver.social/codesync "