
You might even want to pick up a copy of "The Hacker Ethic" by Pekka Himanen.
The Open Library page for the book in question, where you can borrow a digital copy to read, is https://openlibrary.org/works/OL7921693W/The_hacker_ethic
I've never had a problem. I can only recall being asked about it by one or two people. I was just honest and they didn't seem to mind. I got at least one job despite it. I might have missed out on another offer because of it but I doubt it.
The weird thing is that this is just the sort of thing I was warned about before I even got to college. I was told that the norm would be to have many different jobs in my lifetime and not to expect to be with the same employer throughout my career as my grandparents were. I just see it as the new normal; a symptom of a network economy as Pekka Himanen describes in The Hacker Ethic and the Spirit of the Information Age. A bunch of people get together, build something cool, make some money and move on. We're not in the business of building widgets on an assembly line after all.
But maybe my path has allowed me to be blissfully ignorant of the whole "job-hopper," conundrum. I'm sure it still exists. I just think it's a very backwards ideal in a creativity and knowledge-based line of work such as programming.
Update It's not for a lack of trying to stay on a long-term project. One startup I worked at for 2 years and had no intention of leaving. It was being shuttered and I got laid off. That is a fairly common occurrence for startups in my neck of the woods where funding and investment is anemic and the majority of talent is funneled off to SV.
