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Concept guides/Concurrency/Two writers, one file, a lost update

CodingConcurrency

Two writers, one file, a lost update

Hard4 min read

Questions it teaches

Atomic increment interleaving simulatorMedium25 min Lost update on concurrent incrementsMedium20 min Resource reference use-after-freeMedium25 min Lost update in wallet withdrawalHard30 min Inventory goes negativeHard20 min Counter loses incrementsHard22 min Wallet balance corruption under concurrencyHard40 min Backfill race corrupts denormalized fieldHard40 min

Related

Concurrency Designing data structures Backend internals Reviewing AI code Correctness review

Builds on: Designing data structures

Queues, deques & ring buffers3 min Database deduplication3 min

Leads to: Backend internals

Encoding and schema evolution4 min MAC addresses4 min

Related: Reviewing AI code

Catching AI mistakes3 min Understanding code & docs with AI3 min

Related: Correctness review

Spotting correctness bugs3 min Structured logging3 min

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