Do you have a guide for good commit messages

Here are some HN discussions on commit messages:

https://news.ycombinator.com/item?id=18663032

https://news.ycombinator.com/item?id=19704486

https://news.ycombinator.com/item?id=21835874

https://news.ycombinator.com/item?id=13491879

and https://news.ycombinator.com/item?id=21812772

Explain what the commit changes. Think about the person who’ll read them. Think about your future self who’ll find a bug and search in the commits to understand what happened. "Sources" or "Oops" are the worst commit messages you would hope for.