It depends on the technology used to be honest and the company, normally I would advise the person concerned to make sure they know what technologies they may be working with as they are likely to be asked questions around those. Next be up to date with knowledge about the stack you are likely to work with. Go over some coding best practices and definitely look into design patterns.
We’re a place where coders share, stay up-to-date and grow their careers.
We strive for transparency and don't collect excess data.