Open source projects often start as “by developers, for developers,” but not all developers are the same. Users are the biggest group and they need clear, concise guidance to use the project effectively, while contributors require deeper insights into the codebase and processes. Maintainer experience matters too - making sure that the project is set up to work efficiently and make good use of their time and expertise. This talk explores how to go beyond the README to create a developer experience that caters to all three groups, ensuring your open source project is as welcoming, usable, and sustainable as it can be.