Here is a bunch of feedback: There doesn't appear to be any opportunity for TDD (or any kind of testing or iteration), even for something simple like checking

Here is a bunch of feedback: There doesn't appear to be any opportunity for TDD (or any kind of testing or iteration), even for something simple like checking syntax (I submitted one with a missing ';'). As a result, it does not come close enough to a real-world programming task. Once I had looked around, and failed to find a "run" button, I decided that I'd try just pressing submit, and I got to the "we'll email you" screen. I'm sure I'm not alone. This would account for the very low pass rates. In the real world, this would be like having all your programmers working with a plain text editor and no compiler, and having them commit untested code, in feature-sized chunks, to trunk for the CI server to build and test. Obviously, under the right circumstances, I could do the work on my own computer, and paste the code into your form, but that sort of defeats the purpose of having it online. Following the doctrine that programs are written for humans first, computers second, a human still needs to read the code to work out whether or not it was well written. I don't know if you make this available to screeners. You could try applying some other metrics (e.g. max/mean function length), to give more than a pass-fail.