100% of my work has been internal-facing systems for large companies. Should I compose a portfolio of it? How will a hiring manager be able to differentiate it from a bunch of bullshit?
As an artist, you can almost always point to something, and say: I did this. I designed that. I am credited on a blockbuster film.
As a programmer, you can almost always talk a hot game about how you did something, but you can rarely tie that to proof.
Are you saying that's the hiring manager's problem, not mine?
I got my first programming gig, sans degree, with my portfolio. My boss commented that my website, and descriptions of my projects, is what got me the interview.
Coming from graphic design, a portfolio is par for the course. But, I think some programmers will overlook the need for one. And no, I don't think Github projects serve as the same thing. A supplement? Yes. But, a proper site for your work can do wonders.