What Is the “Bus Factor” of Your Project?

Our team is currently trying to figure out how to work with the bus factor - but that measurement is just one side point of view - good for prevention to lose an important team mates, and helps with planing handover for sure.

We've found another metric (unnamed) what's the person coverage of code (or projects). As we're working in a long living project, we've found that for some code we have there is no single person knowing shit about it. Therefore in case of maintenance - there is a risk that it will take longer - or possibly will be impossible. Guess what - in case of code that we use it's fine to live with this. And in any case, somebody will flex a little bit more to change implementation.

There is another case - when internal projects / CI / CD relies on tools that we've lost maintainers. Knowledge how to build them, where to SSH to restart them is gone. Current action is to spot such systems and reduce our dependency on them.

Our team is ~60 devs. I wounder to how it works for other companies that maintain long living projects.