[eugenejen]

What happened to people who can write successful products but not yet been open sourced?

This happened to John Carmack, Jamie Zawinski. They are probably too busy in making stuffs work then writing answers on Stack Overflow or committing code to GitHub.

[jrockway]

Some people do both. Why gamble on someone who won't show any of his work when you can just pick someone who does?

[nickelplate]

Some people are plenty mentally stimulated at work and don't feel the need to work on their own projects in their spare time. And sometimes your professional accomplishments are significant enough that a side project is not likely to make you a much more attractive candidate. The people who "do both" often don't fall in these categories.

Also a lot of companies don't want their employees to write code for anyone else and will actually see open source contributions as a major red flag.

[jrockway]

Also a lot of companies don't want their employees to write code for anyone else and will actually see open source contributions as a major red flag.

FUD. I work for a very large corporation, and open source was definitely not a negative when hiring me. Many very important parts of our business are based on open-source technologies. (And many aren't, FWIW.)

[eugenejen]

Good point.

But if the code has copyrighted issues, then how can I show publicly? I usually have a copy of repository for my past projects and I don't mind to show it to people who interview me.

Also I think if I need to put code on GitHub, it has to be some software for more generic tasks.