For development manager, this article is probably a good reference when you are doing phone screen to eliminate non-qualifed software engineers. Steve has come up with five essential questions for first phone-screen with an software development engineer candidate:

  • Coding. The candidate has to write some simple code, with correct syntax, in C, C++, or Java.
  • OO design. The candidate has to define basic OO concepts, and come up with classes to model a simple problem.
  • Scripting and regexes. The candidate has to describe how to find the phone numbers in 50,000 HTML pages.
  • Data structures. The candidate has to demonstrate basic knowledge of the most common data structures.
  • Bits and bytes. The candidate has to answer simple questions about bits, bytes, and binary numbers.

Those probably basic, but can screen out someone do not even know/understand those basic:

I’ve been on a lot of SDE interview loops lately where the candidate failed miserably: not-inclined votes all around, even from the phone screeners who brought the person in initially.

It’s usually pretty obvious when the candidate should have been eliminated during the phone screens. Well, it’s obvious in retrospect, anyway: during the interviews, we find some horrible flaw in the candidate which, had anyone thought to ask about it during the phone screen, would surely have disqualified the person.

But we didn’t ask. So the candidate came in for interviews and wound up wasting everyone’s time.

The article also describes in detail on the technical side of those questions and answers.

The Five Essential Phone Screen Questions