Going full stack from mobile, any tips?

I wanna go full stack from my current specialty which is mobile development. Currently what I am doing is making this hobby NodeJS with Loopback back-end. I do it at around 2 hours a day at work after 6 hours doing mobile. Got a bit of experience doing front-end web dev before going native mobile for five years. Any tips to become full stack? Anything to do, avoid, etc?