Experienced Full Stack Developer as Project Consultant/Coach

We are a small NGO developing a Prototype using R / Shiny app / Plumber API. We are looking for a Full Stack developer, who plays the role of consultant/coach for our junior developers. You should have solid experience in API / Microservices / Software architecture / Full-Stack development. The job will be done on a per-hour basis with a few hours per week. You don't need to write actual code, but to consult our junior developers into the right directions. At this moment, our objective is to do a solid but simple WebApp as prototype for a limited number of users. note: as this is an MVP, we have a limited budget. However, if you do a good job, there is a good chance that we will hire you later for a longer time as we go into production.