Great work. I like the effort you made into keeping the experience coherent across platform. Also ordering the interactions by emotional commitment is a smart way to think about it.

Yeah, these are great points. I would expand onto the 3rd point and say twitter can feel bit isolating at first. You have to initially make a real effort to get any genuine connection with others out of it.

but be warned it's very easy to be sucked into the time vortex that is front-end javascript

This would be entirely my concern. If you was to hire someone who just didn't have the technical know how and experience, it could take them hours to execute on something which would take an engineer minutes.

I know this, as a designer turned software engineer, I remember the early days of spending hours of struggle, to achieve something which is actually very simple for me now.

There are people who identify as UI engineers. Perhaps this would be a title worth throwing out there.

absolutely! I previously also would have been a good fit for this job description. Unicorns do exist. It's more a question of how do these people identify, do they look for Engineering jobs or design jobs. I think most likely front end engineering.

I just thought this was a funny answer!

haha, pretty much

Hi Sam, I have spent 5 years as a UI designer and 4 years as a software engineer. I would advise that you look for a Front End engineer for this position. In my experience Front end engineers often care about UI and UX. The technical side of executing rich interfaces is unavoidable. Someone who doesn't have the technical ability to execute just wouldn't be able to do it.