I have a human conversation, make sure the expectations are clear and ask them if they think they can do it. Then I look at some of their work to verify and that's literally all.
No whiteboard, no takehome, no brainteaser, nothing like that.
Go google "how gates hires" or "how jobs hired" ... it's more or less the same. None of this I watch you implement a sliding window in a shared coding environment bullshit.
Let me put it this way. Say your candidates were all award winning scholars with phds and prestigious organizations to their name, then how would you go about it?
With respect but also, you'd still check to make sure it's the right fit, obviously.
Now here's the crazy go-nuts bananas idea - treat everyone with that level of respect. Totally wacky, I know. But hear me out - you can apparently build better teams with trust allocated to trustworthy people as your building block. That starts the day you interview and extends forever, well beyond your time working together.
Because it's self-evident that designing a quick-ramp up process and modular system/good docs makes this a lot easier. It's 2022, you should be able to review checkins on gitlab the first week with a couple of basic tickets.
If folks are too green for that then they can be put thru an internship first. If an obscure language, have them do checkins on a tutorial.
Does your software systems scale to Millions?
What about counterfactuals?
Without that data, your 3-decade hiring process means nothing.
I'm sure someone working in IBM, TCS, AT&T, Booz can all claim that they have been hiring people for 3-decades and give an opinion