I've built several versions of a log based db with composite keys over the years, the most complete version so far in Common Lisp: https://github.com/codr7/whi

I've built several versions of a log based db with composite keys over the years, the most complete version so far in Common Lisp: https://github.com/codr7/whirlog https://github.com/codr7/whirlog I've found that reinventing wheels is a great way to learn, even if you never use them.