Yes. This is a far more difficult problem than people seem to appreciate. Except for open, solo projects, finding out the work that people have done is challenging. Which goes a long way to explain the difficulties of the job-finding and interview process.
Consider the common case of the average developer (especially so for a non-web developer). They've worked on several closed source projects on which the extent of their participation is non-trivial to determine. Ultimately you have to talk with them and suss out what they actually know, which is at least a day long process in order to attain any degree of accuracy.
Even if they've worked on open source projects, it may take a lot of effort to grovel through their commits to find out whether or not they're telling the truth on the size of their contributions.
Incidentally, all of this is a good reason to have your own personal solo project and your own personal blog, though it can take a lot of effort to do so.
Consider the common case of the average developer (especially so for a non-web developer). They've worked on several closed source projects on which the extent of their participation is non-trivial to determine. Ultimately you have to talk with them and suss out what they actually know, which is at least a day long process in order to attain any degree of accuracy.
Even if they've worked on open source projects, it may take a lot of effort to grovel through their commits to find out whether or not they're telling the truth on the size of their contributions.
Incidentally, all of this is a good reason to have your own personal solo project and your own personal blog, though it can take a lot of effort to do so.