I usually supplement the interview with a take home project, because front end web dev (emphasis on web) is about building interfaces and managing state really well and that is hard to test in an hour!

Some of the more domain specific stuff is about building a scalable components library that your team can use, testing your code, building assets in the most elegant way possible (gulp, webpack, grunt). So make sure you're very honest with your resume!! (dishonesty is bad).

For the case of front end web, here is what I would ask from the top of my head (thinking aloud):

- A good interview will have some pair programming. I usually like to give a very simple mock. These mocks will have a simple task where I will ask you to implement me a two column layout, or a popup window. Therefore I'd like to see that you have strong fundamentals of CSS, HTML, and Basic DOM manipulation using JavaScript. Nice interviewers will allow the use of google!

- You should understand how a network request and response works. I'll probably ask you to teach me what an AJAX request is to start. I hope to have a good conversation because I forget things often and like to learn from others.

- I will probably ask you what are some ways to implement components that won't produce side effects in a large codebase.

- I will probably ask you questions about how you plan to work with Design and other product stakeholders to ensure that you're able to iterate quickly on the front end. This is because requirements and design changes frequently (more common with companies that are focused on product versus growth/retention).

- I will ask you how you approach testing, and how do you ensure your interface will work cross browser, cross device.

- If you're really a generalist and you have no front end experience but a lot of other programming experience, I'll probably ask you to serialize a network response with JSON, where you'll create a map of ids and their resources (for fast access!) and walk through an object tree to do this. We can probably pseudo code this if you've never touched JavaScript and know nothing about its data structures (this jon snow case is rare, like jon snow).

- If you're really junior I'll ask you a generic algorithm question because I'm probably going to train you on the job anyways. No one should be punishing junior people for being junior with stupidly difficult domain specific questions. Don't work somewhere where they punish you for being junior because they won't realize how much potential you have (you have a lot).

Last note: Good luck and have fun, remember to be yourself and try your best.