Continuing the discussion from This is "E" and my co-founder and CEO Jeremy Johnson is here with me, ask us anything!:
We started out focused on the MEAN stack but quickly diversified into Ruby on Rails, Python, iOS, Android, and a number of others. Ultimately, we care less about a specific language or framework and more about ensuring that all Fellows know how to learn and know how to solve complex problems. A great developer needs to do more than memorize a language - they need to be able to evolve as the tech ecosystem evolves and understand how to analyze different paths for solving a problem scalably.