Architecture of Nautilus, the new Dropbox search engine

Search presents a unique challenge when it comes to Dropbox due to our massive scale—with hundreds of billions of pieces of content—and also due to the need for providing a personalized search experience to each of our 500M+ registered users. It’s personalized in multiple ways: not only does each user have access to a different set of documents, but users also have different preferences and behaviors in how they search. This is in contrast to web search engines, where the focus on personalization is almost entirely on the latter aspect, but over a corpus of documents that are largely the same for each user (localities aside).

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