The barriers are all in the mind. The simplest way to upgrade skills is to work with teams working on problems of interest to you, where you have to meet up wi

The barriers are all in the mind. The simplest way to upgrade skills is to work with teams working on problems of interest to you, where you have to meet up with them, atleast once a week if not more. The social aspect is what drives learning. Doesn't matter if you are working full time. Find a subject that interests you THEN find/contact research labs/profs/startups working on it. Tell them you have X hours a week (for 3 or 6 months) you want to devote to it and ask them for an assignment. If you have more experience and skill than the avg grad student they employ, it's easy to find a project. I have done this with incubators, univ labs and research labs close to me. I am luckily in a large city, where once you start looking, you will find all kinds of interesting characters doing interesting things. Follow their blogs, twitter feeds and github repos. Identify where you want to contribute. Make a small bug fix or document some aspect of their code and the door opens.