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🧩 Challenges · Rust

Build it, break it, predict it, or recall it. Pick a challenge and prove you've got it.

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bug hunt basics

debug
easy medium hard

bug hunt strings and collections

debug
easy medium hard

code review idioms

debug
easy medium hard

bug hunt concurrency

debug
easy medium hard

predict loop output

predict
easy medium hard

predict iterator result

predict
easy medium hard

predict integer ops

predict
easy medium hard

recall ownership and moves

recall
easy medium hard

recall borrowing errors

recall
easy medium hard

recall numbers and casts

recall
easy medium hard

recall option result question mark

recall
easy medium hard

recall collections and costs

recall
easy medium hard

recall strings and utf8

recall
easy medium hard

recall iterators and closures

recall
easy medium hard

recall lifetime elision

recall
easy medium hard

recall common compiler errors

recall
easy medium hard

recall pointers threads locks

recall
easy medium hard

recall async vocabulary

recall
easy medium hard

recall derives and std traits

recall
easy medium hard

recall modules visibility and cargo

recall
easy medium hard

recall unsafe powers

recall
easy medium hard

recall serde attributes

recall
easy medium hard

build a counting loop

construct
easy medium hard

build a running total

construct
easy medium hard

build a filter loop

construct
easy medium hard

build a helper function

construct
easy medium hard