Is there any viable open source alternative to commercial antiviruses?

For my personal needs, I now do not use any AV on most of my Win10 computers, but this requires some serious discipline.

For obvious reasons, I can't really do that on users' computers at work and I was wondering if you 'd know any viable open sources alternatives to Defender, Kaspersky, or any other commercial AV with a free tier.

I stumbled upon Armadito but it doesn't really inspire confidence as their website has security issues and no way to download the software. Any Idea?