What are the best practices for maintaining Swift code in large projects?

To maintain large Swift projects, break your code into small modules so you can reuse parts easily and handle changes more effectively. Always use clear, consistent names for files, classes, and variables, and follow Swift style guidelines. Rely on protocol-oriented programming to keep sections of your code loosely coupled and flexible for future growth. Protect code sections by managing access levels and limiting unnecessary links between parts. Regularly improve and clean your code to reduce confusion and the risk of errors. Make sure you run unit tests to catch errors early, and use Swift's type safety and optionals to avoid most runtime bugs. These techniques help large Swift projects stay reliable, clear, and easier to manage.