I am a bit of a jack-of-all-trades. I generally bill myself as the "&" in R&D, bridging the gap between academic researchers & mathematicians and mainstream software engineering. I.e. I can do a bit of classifier design, but most of my focus tends to be on build systems, automated test systems, parameter tuning, data quality monitoring and all the nuts-and-bolts stuff that most researchers don't want to be bothered with. I am way too OCD to spend my day producing "research quality" code, and too wary of BS for my output to be just research reports and academic papers. I prefer shipping product, if you know what I mean?
I lost interest in DeepMind when I could not figure out what their business was after a couple of interviews. (The startup that I was previously working for had just run out of money). More fool me. Heh.