Your project is a very strong filter, both positively and negatively: 1. it will select coders who are very familiar with that exact same stack, and find your

Your project is a very strong filter, both positively and negatively: 1. it will select coders who are very familiar with that exact same stack, and find your test trivial (good) 2. it will also select bad coders desperate for a job, who will google to death to eventually come to a solution, even though you would never hire those people (bad) 3. it eliminates good coders who have better things to do than fiddle with installing a different stack, etc. (bad) Overall, as long as you get enough people from the first category, you win. If it turns out that you are having problems convincing people to take your test, think about category 3 again...