I've worked 3x12, 4x10, and 5x8, without AI. I think I was most productive on the 3x12 schedule. On the days I worked, I was able to lock in and get a lot done, and had a significant amount of time outside of the normal working hours, which were free from meetings and distractions. During those 3 days all I really did was work and sleep. On the 4 days off I was able to rest and recover and actually have a life. It also gave my mind time to process issues in the background. When I had an ah-ha moment during my time off, I could note it down, and when I showed up on a work day, I was able to solve some of those problems I wasn't able to solve in the moment. It was a great system.

I've been trying to figure out how to bring the idea up to my boss of going back to it... at least the 4x10.

I think that’s more about what you do than how you do it. And sometimes when to do it.

You could try a data engineer’s life which is full of meetings, ad-hoc tasks and other BS —- everything that screams that this is not a real engineer job.

> During those 3 days all I really did was work and sleep.

This is why 3x12 is not workable for average families. If you have kids and want to see them, 3x12 only works if you start really really early, then get to bed early when the kids do too.

I enjoyed 4x10 when I did it, but there were some real problems with some employees trying to adapt. Anecdotally we were seeing a lot of people who would barely work until the 8 hour mark and then just zone out or socialize while they waited the clock out at the end of the day.

Which is all too bad for those of us who work well with longer days.

in tech, we (frequently are expected to) work 5x12!