Haha, great question! I think it was at Algolia when I first heard the term. We had a guy who was a designer and illustrator by background but had gotten very good at front end coding, enough where he could make his project ideas come to life end-to-end. He called himself a devsigner, and since then I've seen some other people doing it too.
I'm sure there is more backstory here though widely speaking, so many titles out there 😛
Usually devsigned/devsigner has a more negative (though not usually too negative) connotation than that. Usually it refers to a page or app or feature &c which has not been fleshed out by an actual designer and for which a developer has done their best to make it look good. Obviously the results depend on the design chops of the dev
This was my thought when I saw it.
We're a place where coders share, stay up-to-date and grow their careers.
We strive for transparency and don't collect excess data.