Concurrency & Parallelism
Overview

Concurrency & Parallelism

How to do many things at once without stepping on each other.


Topics

ChapterWhat It Covers
Concurrency & Parallelism FundamentalsProcesses vs threads, race conditions, locks/mutexes/semaphores, deadlocks, optimistic vs pessimistic concurrency control, distributed locks, async I/O, thread pools, the actor model

Why This Matters

Almost every hard bug in production backend systems traces back to an assumption about ordering or atomicity that concurrency violated. Understanding these primitives isn't academic — it's the difference between a design that quietly double-charges a customer under load and one that doesn't.