Ask HN: How to extract number of users from access.log?

I have a website whose main user are advanced software engineers.

I suspect that most of them are using ad/tracking blockers and similar, so google analytics will not count the real number of users.

Is there any good software out there that can give me essentially the basic information about how many real users I got out of my web access log?

I.e. it needs to be able to filter out crawlers/scrapers, and ideally scrapers that have put a fake user agent, but whose behaviour gives them away as scrapers.