I don't know if this is what they meant but I read it as you describe an existing project that you've worked on, not a mini one just for the interview. That's how I've interviewed before.
I’ve encountered both, significantly more of the “build a mini project for us” variety.
I also dislike those because I’ve already got a full time engineering job and a family and don’t have time to put 4-5 hours each into every 3-hour project the interviewers ask for. But 5 years ago I did.
I’ve concluded there really isn’t a single way to interview that checks all the boxes, and if you’re running the interview process you have to pay the costs somewhere, unfortunately.
This is more of a problem than it seems at first. At one place I worked that did mini-project interview most of the hires were currently unemployed and could spend all week on it. (then claim they did it in 3 hours)
> I read it as you describe an existing project that you've worked on
IMHO, there is some risk of violating NDAs. For the most part companies don't care if you share how their tech stack works, but I get nervous about revealing IP.
