I've been working 20 hours a week at a major company for the last 7 years and I love it. Full health benefits.
> What kind of role are you in?
SRE/Programmer
> How did you make the part-time arrangement happen?
I accidentally fell into it when I went part time to do a masters degree to consider switching careers but then, when I decided I didn't want to pursue the other career, I just kept doing part time and my company was fine with it. I work Mondays (7 hours), Tuesdays (7 hours), and Wednesdays (6 hours) and then I have Thursdays through Sundays off. I get paid half of course but it's still a good salary (grateful to be a programmer!).
> What’s been the hardest part of working part-time in tech?
Sometimes it's easier for me to take calls on Thursdays or Fridays instead of pushing back on it (technically I could, but I don't want to jeopardize my part time status). This is fine as I just make up the time in the following week but it means that I can't easily treat Thursdays and Fridays exactly like a weekend as far as scheduling trips, etc.
> Are there specific companies or setups that are more open to part-time roles?
I did it at a huge company so I think it's possible anywhere but I already had a great reputation and my company really wanted to keep me, and I think it would be harder to do without having a great reputation. I get the impression that companies generally don't like doing this because of the possible contagion effect of other workers wanting to do the same, so I generally don't talk about it much at work.
> Any tips, advice, or experiences you can share would be super helpful!
Four days a week part time is much more do-able than three days a week. Don't limit yourself just to companies/jobs that explicitly advertise part time work, though those certainly also make sense to apply to, but just make part time a key part of the negotiation process. Consider emphasizing flexibility.