V8 JavaScript engine

What hackers pick instead

• QuickJSSmall, self-contained, fast C JavaScript engine by Fabrice Bellard that matches almost all of ES2025 and is easy to embed. Critics say it is much slower than JIT engines such as V8.33recommend
• MicroQuickJSTiny JavaScript engine for microcontrollers and embedding, praised for its small memory use and sandboxing. Main caveat: it implements only a subset of JavaScript close to ES5.19recommend
• JavaScriptCoreApple's JavaScript engine, used by WebKit and Bun, with well-tuned JIT performance and a long track record on consumer devices.14recommend
• Boa JavaScript engineRecommended for being standards-conforming and very easy to embed in Rust apps; the most common caveat is slow performance compared with V8 and other engines.14recommend
• SpiderMonkeyMozilla's JavaScript engine that people find well maintained and self-contained; the most common caveat is that it is slower than V8.8recommend

Every quote

The 40 most detailed of 103 comments. Each links to the original.

1. dynamic language implementations that are performance-competitive with static language implementations, like Javascript's V8/Bun/Deno

   Recommends · Jun 2026 · in “Elixir v1.20 released: now a gradually typed language”

2. JS has the fastest, most robust and widely deployed sandboxing engines (V8, followed closely by JavaScriptCore

   Recommends · Dec 2025 · in “Anthropic acquires Bun”

3. v8 and JSC also have decades of performance tuning across basically every consumer device.

   Recommends · Aug 2026 · in “DeepSeek Harness”

4. V8 does some crazy stuff that makes JS one of the fastest interpreted language there is.

   Recommends · Mar 2026 · in “Making WebAssembly a first-class language on the Web”

5. The benefit is that JavaScript JIT compilers have a few decades of research behind them

   Recommends · Mar 2026 · in “Python: The Optimization Ladder”

6. has an unstable API, and an absolutely massive unwieldy Google-style C++ code base

   Mixed · Nov 2025 · in “Boa: A standard-conforming embeddable JavaScript engine written in Rust”

7. V8 is actually a nice case for CHERI since you can easily sandbox the JIT'd code

   Mixed · Jul 2026 · in “RISC-V Is Inevitable: State of the Union Keynote Argues”

8. per-origin sandboxing, properly implementing web standards, V8, developer tools

   Recommends · Apr 2026 · in “Mozilla's Opposition to Chrome's Prompt API”

9. They basically revolutionized the web with the JavaScript V8 engine in chrome.

   Recommends · May 2026 · in “VS Code inserting 'Co-Authored-by Copilot' into commits regardless of usage”

10. I think that the V8 team has done a fantastic job of securing their engine.

    Recommends · Sep 2026 · in “Actively exploited sandbox RCE in all Chromium versions”

11. Chrome and v8 was just stupidly faster than any other browser and JS stack

    Recommends · May 2026 · in “Google Cloud Fraud Defence is just WEI repackaged”

12. They created V8, kickstarted the modern browser wars with Chrome.

    Recommends · Jan 2026 · in “Google AI Studio is now sponsoring Tailwind CSS”

13. JS though (via V8 and other engines) has been surprisingly fast.

    Recommends · May 2026 · in “The Green Side of the Lua”

14. V8 is faster than LuaJIT. But sure, it has a large binary size.

    Mixed · Feb 2026 · in “Vim 9.2 Released”

15. With how much engineering was poured over V8, I don't doubt.

    Recommends · Jan 2026 · in “New Safari developer tools provide insight into CSS Grid Lanes”

16. none of them could beat V8/Node JIT in the majority of cases

    Recommends · Oct 2026 · in “Beating the compiler (2024)”

17. v8 is one of the most advanced JIT runtimes in the world

    Recommends · Dec 2025 · in “Anthropic acquires Bun”

18. The chrome browser and the v8 engine are innovations.

    Recommends · Feb 2026 · in “Microsoft offers guide to pirating Harry Potter series for LLM training”

19. v8 is a pretty fast engine and an engineering marvel

    Recommends · Mar 2026 · in “Zig – Type Resolution Redesign and Language Changes”

20. V8 (and other Javascript JIT engines) are very good

    Recommends · Jan 2026 · in “Is Rust faster than C?”

21. V8 is extremely optimized for script startup time.

    Recommends · Sep 2026 · in “5x faster Edge Functions: V8 isolates to Firecracker MicroVMs”

22. V8 arguably the fastest interpreter in existence

    Recommends · Sep 2026 · in “The JavaScript Midlife Crisis”

23. Chromium has V8 which is the faster JS engine

    Recommends · Sep 2026 · in “I switched to Brave”

24. The engines are brilliant -- Self's legacy.

    Recommends · Jan 2026 · in “What Happened to WebAssembly”

25. Even basic arithmetic operations on a TypedArray over a SharedArrayBuffer is slow AF in v8 compared to a "native" JS Array

    Criticizes · Jun 2026 · in “Bun has an open PR adding shared-memory threads to JavaScriptCore”

26. that just means less outrageously slow, not that it will be remotely competitive with native code

    Criticizes · Sep 2026 · in “Cf: The Agentic CLI for the Cloudflare API”

27. There's been a constant stream of v8 VM sandbox escape discoveries since its dawn of course.

    Criticizes · Feb 2026 · in “Python interpreter written in Rust for use by AI”

28. The v8 JIT is very complex and can lead to sandbox escapes if there are type confusion bugs.

    Criticizes · Sep 2026 · in “5x faster Edge Functions: V8 isolates to Firecracker MicroVMs”

29. finding a wrapper for it that doesn't come with a big warning NOT to use it as a sandbox

    Criticizes · Jan 2026 · in “JavaScript engines zoo – Compare every JavaScript engine”

30. the top ones seem to be V8 bugs where the JIT is coaxed into generating exploitable code

    Criticizes · Jan 2026 · in “Servo 2025 Stats”

31. I rarely get performance within an order of magnitude of single-threaded C from V8

    Criticizes · Nov 2025 · in “Notes by djb on using Fil-C”

32. Trying to embed V8 and keep up with V8 API changes would be a huge amount of work

    Criticizes · Nov 2025 · in “Boa: A standard-conforming embeddable JavaScript engine written in Rust”

33. Looking at amount of JIT related (for example type confusion) security bugs in V8

    Criticizes · Oct 2026 · in “Python's experimental JIT to be removed”

34. V8 was not a fork of it and was started from scratch, but V8 was designed to replace it in the Blink fork from WebKit

    Mixed · Dec 2025 · in “Anthropic acquires Bun”

35. v8 on the other hand is much harder, although I will say I found the code better organised and explained than React.

    Mixed · Feb 2026 · in “I Don't Like Magic”

36. two big corporations have invested a lot of money and effort into making V8 and TypeScript, and now it's useful

    Recommends · Feb 2026 · in “JavaScript-heavy approaches are not compatible with long-term performance goals”

37. I frequently find that V8 optimisations yield sufficient performance without needing to delve into WASM.

    Recommends · Mar 2026 · in “Making WebAssembly a first-class language on the Web”

38. handles all the exec/eval, monkey patching and object system abuse you can do in JavaScript just fine

    Recommends · Oct 2026 · in “Python's experimental JIT to be removed”

39. Reaching for an existing Javascript interpreter such as JavaScriptCore or V8 is the logical choice.

    Recommends · May 2026 · in “Native all the way, until you need text”

40. Good on the V8 team. Sounds like they’ve figured out a way to get the performance of green threads

    Recommends · Apr 2026 · in “What Async Promised and What It Delivered”