Very typical to move in to a position where you are designing the code more than writing it. Junior devs probably can't architect a system as well and especially if you already know the system well you are in a better position to know the best design. But with that comes writing, documenting, organising a team, planning work, estimating, interacting with project management and customers, going through the SDLC hoops. The junior devs get given a spec / design and "just have to type out the code", with the seniors there to support, guide / mentor. This leaves very little room to code yourself, and the bits you do do might be the more complicated bits, in which case you should think about bringing along a junior for the ride and teach them. Or they might be the simple tools and libraries that you can do in a couple of hours because that's all the time you can find to do it in.