Knuth was being paid by Burroughs to implement an Algol-58 compiler in 1960. He’s still programming, and seems to have advice for others on the subject. But I don’t expect to see him here. Congratulations on being in that company, and may it long continue.
Or perhaps I'd classify him as the somewhat more sycophantic "longest working genius" or "longest working cool guy". Heck, Knuth was uniquely awarded a master's degree for his bachelor's because his work was considered so outstanding, he's an organist and composer, and he's hilarious. I love this quote about him: "If you had an optimization function that was in some way a combination of warmth and depth, Don would be it."
A quote from him in an interview I found: "Indeed, as mentioned above, my life's work was to be a teacher."