[gortok]

I only see two possibilities:

1. Require developers to code on demand during an interview (personally, I have a hard time with this; the pressure of an interview is not a normal working situation).

2. Allow someone to do it on their own time, under no time pressure. (I advocate paying them for their time at a fair market rate).

Do you see another way of a senior developer demonstrating their abilities without hitting either of the two above?

[ryandrake]

Ask the candidate to thoroughly review code during the interview and offer insight. See if they can spot undefined behavior, if they can improve an already-good solution, and ask what their approach would be to refactor it. If they are truly senior programmers, their actual job will be reviewing more than they write anyway, and you’re not hiring them for their ability to crank out a quicksort implementation.

For the junior folks, sure: have them burn through homework.