My own view (I didn't work with everyone). Most of these people are not programming anymore. FB was notoriously clowntown early on so this is a list is more about my nostalgia than great programmers.
  1. epriestley
    If a musician has perfect pitch, it helps them be a great musician but it's excruciating for them to hear anything off key. This is Evan with programming. He was the best and the fastest but working with n00bs who made mistakes drove him crazy. To cope, he would drink heavily in the office and eventually work only on projects with hand picked minions who would do exactly what he said. Eventually he couldn't take it anymore and left to start Phabricator where he's the only programmer. The best.
  2. sgrimm
    One of the most reasonable people I've ever met, perhaps underrated because he was less loud and tried to reason through conflict so much. He was much older than most people who were roughly college age. He had a literal gray beard. People would say things like "Steve's C code is absolutely perfect. I can't find anything that should be changed." Checks every box on what makes a good engineer and a good company employee. Now at GiveDirectly, the analytical person's dream nonprofit. Great dude.
  3. mcslee
    When there were errors in the logs after pushing a new version of the website, we would race to see who could fix them first. Slee won ~80% of the time. Your best hope at beating him was if two bugs showed up at the same time and you guessed right and worked on the other one. Or if you wrote the buggy code and knew how to fix it. In those cases, your odds improved to about 50/50. In spite of his talent, Slee's heart was never in it and he's out of the game now, doing installation art and DJing.
  4. haiping
    Works in office 9-3. Picks up daughter from school takes her to figure skating practice. Plays Counter Strike for a few hours. Then all night does something like implement a compiler for PHP. By himself. That he's told is too crazy to work on and he's not sanctioned to spend his time on. That he eventually gets to work. That saves the company literally 💯s of $$MM. Does not speak English clearly or write emails that make sense. A mad genius. Just announced he's going to go work at Alibaba.
  5. ari
    Ari was my favorite. My work BFF. Slee's roommate from college. Almost as fast and clean, but maybe a better theoretical mind and I like his APIs better. Not afraid to stir things up (in a good way) or call something stupid which made stupid people dislike him. Smart in other ways beyond programming too which always comes in handy. I wanted to start a company with him but his wife got a professor job at UW and he moved to Seattle and he has a baby now. Check out his travel startup, Vamo!
  6. moskov
    Moskov is kind of forgotten as a cofounder of Facebook but for a window of time, I think he was actually more important than Mark Zuckerberg. Without him, Facebook would have crashed and burned in 2006. He had only taken one intro CS course when he dropped out to work full time on Facebook but he had great instincts and made some incredibly sharp high level architectural decisions without help that set the company up to scale in a way that Friendster, MySpace, and Twitter failed to.
  7. srush
    My protege. Sort of. Except he was better at theory and practice than I was so I would just give him really big assignments and get out of his way and then we could argue about high level stuff. Main weaknesses were: a little sloppy when going too fast, sometimes too much of a libertarian in his views on product. But just a little. Probably the best theoretical computer scientist who worked there. Left to go to MIT become a computer science professor in Natural (human) Language Processing.
  8. marcel @marcel
    Marcel w/ another guy Putnam wrote a FB virus that would make your profile look like a MySpace page and made anyone who looked at an infected profile get it, so moskov got them to drop out of college and work security. Then he just worked really hard and became the best at a lot of things. One example: he released a way to sandbox JavaScript he'd made in 3 weeks and Google called us up and brought over 6 PhDs who'd been trying to do the same thing for 3 years but weren't done. Now retired ATX.
  9. rhe
    On his first day, I assigned Ray a bug no one had been able to fix in 2 years and 36 hours later, I got an email about how a certain combination of Norton antivirus version 24.3 and IE6.0021 and Adobe Flash triggered some erratic browser behavior that was causing the problem. A true engineer. Would build weapons out of PVC pipes in his spare time. Or invent the perfect steak cooking machine, etc. Side note: i mispronounced his name for over a year. It's "huh" not "hee". Still works at Facebook.
  10. scott
    Almost singlehandedly built and maintained the original FB photos w/ tagging product before there were nice things like AWS that made that trivial. Or lots of blog posts to draw on for advice. Was so good, practical, smart, good choices, always willing to roll up his sleeves, but then got sucked into an intense girlfriend and completely checked out mentally. Lives in LA and has a baby now.
  11. ola & btrahan
    Neither of these guys were the best in terms of doing anything visionary but they both just cranked out an incredible amount of very solid application code. Especially in important but unsexy areas like signup flow and spam management. Incredible amount = more than 2x anyone else besides mcslee. Deserving of this spot on the best programmers list and would rank even higher in the Hall of Heroes. Bob works with Evan on Phabricator. Ola still works at FB.
  12. Honorable mentions:
    boz, aditya, jwang, jtung, dcorson, marck, vernal, probably a bunch of others I'm forgetting, esp once you get to 2008 and beyond.