I also had this problem with hiring a front-end developer. Someone was really good at the theory, but practically couldn't handle himself. I currently do a job

I also had this problem with hiring a front-end developer. Someone was really good at the theory, but practically couldn't handle himself. I currently do a job interview where we start from a super easy app, and then I ask "how would you add feature X", then I go to the next (predefined) step. The challenge of the test is that we run into certain problems. Some senior devs can foresee them, but most don't. Then the question comes "Why isn't this working and how to fix it". I've done a crazy amount of interviews already, and this kind of job interview gives me the most confidence. I didn't have any false positives anymore. You could see the test as "There is this junior that is stuck on something, can you help him out". I want my candidates to be able to deal with the weird shit, and in the end that requires a proper understanding of the underlying technology. I don't like "take home" assignments, because you never know that someone's software dev spouse is sitting besides them. We have a HackerRank test to first filter out the worst, and next stage is this interview I described. We use the same for both juniors and seniors.