you can easily do it if you have a bullshit dayjob, perhaps through no fault of your own (i.e. you work for a dysfunctional organization with tons of money and no direction)
in fact... it's probably one of the best ways to launch a bootstrapped company. it's both the motivation and the sustenance to do something meaningful with your career.
most people just surreptitiously look for a new job while on the clock, or dick around until the gravy train stops, but you can also just do your easy-ass dayjob and work on your startup at night until it's time to switch.
> in fact... it's probably one of the best ways to launch a bootstrapped company. it's both the motivation and the sustenance to do something meaningful with your career.
It is possible with good motivation and caffeine. It is not sustainable long-term but you should be able to get a good 4-8 years out of it while you are young and in good health. See: college students at high-workload universities.
In my case, it wasn't very long. I had a tendency to stay up till 4-5 AM working on my side project, and would tend to get in 1-2 hours late. I was fired after two months of this.
It wasn't the only reason I was fired, of course; there were some other reasons, ultimately coming down to political-cultural clashes. But it was by far the lowest-hanging pretext. I seldom made it in before 10:30 - 11 AM.
I got away with it with those of my ex-employers that were technical companies or had an engineering-driven culture. The last one - from which I was fired - was more the opposite of that.
You shouldn't have a problem if you have a normal employer with a technical culture. Everywhere I've worked has had flexible working hours(within reason), so getting in between 9-10 shouldn't be a problem, and the culture in the US is such that getting a couple cups of coffee while you read email and the company IRC/Slack isn't really a problem in a decent working environment. If it takes you longer than 30-45 minutes to be productive though, or you have a long commute, maybe you should get more sleep :p
If you're dedicated and it's something you really want I don't think that's an impossible schedule to follow. 5 hours sleep, 8 hours in the office, dinner, 6 hours personal project. Do that Mon-Fri and relax on the recuperate on the weekend or do fewer hours in the evening and make up for that on the weekend.