🧒 Explain like I'm 5
You have 10,000 books, but the shelf only displays 10. Instead of showing all 10,000 books (which would collapse the shelf!), you only place the 10 visible books, and each time you scroll, you swap the books in and out. The viewer thinks there are 10,000 books, but the shelf always holds around 10.
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Senior-level deep dive: internals, pitfalls, and a self-interview ladder.
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