At staff and principle level, the job becomes mentoring and working with other senior people under you. There might be a business need/problem, and you have th

At staff and principle level, the job becomes mentoring and working with other senior people under you. There might be a business need/problem, and you have the vision to address it. You gather the requirements, do feasibility studies, evaluate the technologies, nail down the architecture, design the components, and work closely with other senior engineers on the prototype/design/implementation. You might code up the prototype and proof of concept during the exploratory phase. You might code up couple components you believe you're the expert in doing it. At the end of the day, you're the voice and the advocate to ensure your end-to-end vision is implemented.