Endless mode

Bug Hunt ∞

We take a working codebase, inject 1–3 realistic regressions with a mutation engine (26 bug operators: off-by-one, flipped conditions, missing await, wrong status codes, swapped sort order…), check that the tests catch them, and hand it to you. Endless fresh reps until spotting bugs is reflex.

Difficulty

Codebase language

24 codebases

hunts played

hunts cleared

current streak

best streak

Bug species you've caught

Equality flipped

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Off-by-one boundary

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Comparison reversed

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&& / || swapped

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and / or swapped

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Negation removed

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Missing await

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Missing return after response

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Wrong HTTP status

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Update returns old document

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find() instead of findOne()

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Arithmetic operator swapped

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Literal off by one

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Sort direction flipped

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min/max swapped

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Boolean literal flipped

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Middleware never calls next()

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populate() removed

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Collection compared instead of its size

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len() dropped

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range() bound off by one

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Slice bound shifted

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`is None` inverted

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