V8pedia
V8pedia
A source-level guide to the V8 JavaScript engine
Not a quick handbook — a serious, evidence-first walkthrough of how V8 parses, compiles, optimizes, and garbage-collects, aimed at people who want to become contributors.
Unofficial
This is a community project. It is not affiliated with, authored by, or endorsed by Google or the V8 team.
Every claim is backed by a pinned permalink into the V8 source tree at commit fb8be11.
The tiering pipeline, in depth
Ignition → Sparkplug → Maglev → TurboFan. Why four tiers exist, how V8 decides when to climb them, and how deoptimization unwinds back down.
Hidden classes & inline caches
The two inventions that make dynamic property access fast. Maps, transition trees, descriptor arrays, and the IC state machine.
Orinoco — the GC
Generational, concurrent, incremental, parallel. Scavenger, Mark-Compact, write barriers, and the engineering that keeps pauses short.
Always grounded in source
No hand-waving. Concepts are tied to real files and line ranges, pinned to a fixed commit so the links never rot.