When looking for talented engineers I know of no other community with a higher signal/noise ratio than HN (well maybe Stackoverflow?).
I also know of no project to work on that is like Facebook Photos. The team is about the size of an angel funded startup, yet the scale of the fbPhotos is larger than any other app (Facebook or not) that I know of. By almost any metric it's an order of magnitude larger than any other photo sharing website.
=====Why?===== You'll work on hard problems at a huge scale. Expect to be responsible for mission critical features that will touch hundreds of millions of people. You'll be deploying code your first week here. I'm not kidding. This isn't HR-speak.
Client-side image editing algorithms, third-party API integration, data processing & warehousing, facial recognition, hi-res uploads, image matching[1], ... there are plenty of hard problems to solve.
I can promise you that it won't be easy, but it will be rewarding.
=====Interested?===== Don't email recruiting, I'll refer you internally [2]. Find my Facebook email in my profile. Use it to email me 3 sentences. One should be why you're excited about photos (or hard problems). Another should describe a cool project you've worked on. Links/examples of deployed code is best. The last sentence should be why you're going to pass Facebook's engineering interviews [3].
Hesitating? Go ahead and send that email. It might just be the best decision you make today.
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1. http://scholar.google.com/scholar?hl=en&q=robust+image+hashing - does that excite you?
2. Internal referrals are given priority. Also, there is a referral bonus. Once you complete Bootcamp and join the photos team I will give 50% to you and 50% to the photos team (for trips, cool toys, etc).
3. I don't have the authority to bypass the standard interview process. There will be lots of algorithm questions (sorting / tree traversals, etc.) http://www.glassdoor.com/Interview/Facebook-Engineering-Interview-Questions