So I have written my entire backend for my web and mobile app (I'm using Expo for it) and now I have encountered a problem which is how to get authentification to work on them. I have done some research and passport.js looks like the best option but I can't figure out how I could use it in next.js serverless functions since all the tutorials are for Express and just me trying to write the code from the tutorial in a serverless function way is not working. I don't know how to continue. Any help is appreciated. Thanks in advance!