Pyrefly is a new open-source type checker and IDE language server for Python, developed by Meta. It's written in Rust, emphasizing speed and a great developer experience. The project aims to provide instant feedback, making Python typing feel seamless and efficient. This episode of Talk Python To Me features Abby Mitchell, Danny Yang, and Kyle Into from Pyrefly. They discuss the project's motivations, design, and integration within the Python typing ecosystem. The episode delves into what Pyrefly is, why it was created, and how it functions. Several links are provided, including the official website, documentation, and GitHub repository. Listeners can find the project information through various channels, including the show notes and resources. The episode explores Pyrefly's potential to enhance Python development workflows significantly. This initiative highlights the ongoing advancements in Python tooling and type checking. The hosts and guests provide insightful details about Pyrefly.