There's definitely value in putting documentation where it will be seen. For developers, writing in a code comment or commit message is a good bet. If there's a

There's definitely value in putting documentation where it will be seen. For developers, writing in a code comment or commit message is a good bet. If there's an issue, they'll be in the code, and they'll be in the commit log, and they'll see what you've written. At times I've been asked to document things in a company wiki. Typically nobody reads it and it never gets updated when others make changes to the code.