I prefer to have multiple short interviews with different engineers rather than a single multi-hour long one with only one engineer. You get better feedback and it helps against bias.
Not only that but a "toy JS app" implies the candidate knows JS at all. If it's college recruiting, you are better sticking with algorithms since you know that they know it.
To be clear, the goal is to watch the candidate build something using the prerequisite skills expected for the position. I'm not prescribing 3 hour sessions, or JavaScript. Target a 45 minute session. Target whatever tools, languages, etc are expected for the role. Maybe that means being language agnostic. Whatever is appropriate.
Watching folks make something -- for any significant duration -- is perhaps a better estimator of a candidate's genuine job ability than testing how well they approximate an algorithm textbook. Well...that's the assumption, anyway.
I prefer to have multiple short interviews with different engineers rather than a single multi-hour long one with only one engineer. You get better feedback and it helps against bias.
Not only that but a "toy JS app" implies the candidate knows JS at all. If it's college recruiting, you are better sticking with algorithms since you know that they know it.