If you want to impress someone, publish your side project, whatever that means for the type of project it is. Of course the code needs to be public on GitHub o

If you want to impress someone, publish your side project, whatever that means for the type of project it is. Of course the code needs to be public on GitHub or somewhere similar, but if it's a web project, publish it to the web. If it's an app, publish it to an app store and have it on your phone in the interview. The reason people aren't as interested in side projects is that most aspects of professional software development are optional in side projects. The vast majority of side projects are done alone, and for a very narrow purpose: write a command line utility to learn Rust, write a web app to work through a design idea for it, write a game for the sake of implementing a pathing algorithm. As a result, in most cases programmers rightly neglect 95% of the work that it would require to produce a version for public consumption, and on top of that, they don't have to communicate with product, QA, or other developers. Building something that is fit for purpose is usually orders of magnitude easier when the purpose is to learn something, satisfy curiosity, or solve the narrow version of a problem that you are personally facing. Because of this, interviewers have very low initial assumptions about what it means when you say you did something as a side project, and you'll have to show them.