There are only¹ 5 hard problems in #computerScience and #programming: cache invalidation¹, naming things¹, naming people², people's names³, off-by-1 errors¹⁺⁴, and self-reference⁴.

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¹ https://martinfowler.com/bliki/TwoHardThings.html
² see post above by @arialdo
³ https://kalzumeus.com/2010/06/17/falsehoods-programmers-believe-about-names & & https://mas.to/@yournameisinvalid
⁴ see this post; but also the halting problem and whatnot