Speaking of READMEs, I like to try to have one in each directory. This naturally happens if you have modules or libraries in a repo, each with their own directo

Speaking of READMEs, I like to try to have one in each directory. This naturally happens if you have modules or libraries in a repo, each with their own directory. But even if you have a monolith with tons of HTTP controller classes, grouping them by domain and providing a guide to the domain is really nice when you're on an expedition through the codebase. It's a place to take notes about decisions, introduce domain-relevant terms, collect links to further reading, etc. all stuff which helps people completely unfamiliar with the code, or jogs the memory if the author was you-from-the-past.