Language internals

How your languages work underneath

Each guide explains what the runtime and compiler actually do, shows it with programs you can run, and then tests you with interview drills. Every output on these pages was produced by running the program.

Python internals

CPython 3.12

How CPython runs your code: objects and refcounts, bytecode and the eval loop, dict and list internals, descriptors and metaclasses, generators, asyncio and the GIL.

The object modelExecutionData structures insideClasses and attributesControl flow and concurrencyProgramsMixed practice

13 chapters · 240 drills · 254 runnable examples

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C++ / OS Guide

C++20 · GCC and Clang

The original guide: objects and vtables, threads and locks, networking, memory management and move semantics.

OOPThreadsMemoryMoves

26 chapters · 847 drills

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