# JavaScriptCore

14 Hacker News commenters recommended JavaScriptCore and 5 criticized it, November 2025 to November 2026. It was recommended in 9 of 13 months. It meets the Hacker Approved badge rule.

**Verdict:** Apple's JavaScript engine, used by WebKit and Bun, with well-tuned JIT performance and a long track record on consumer devices.

## Why people recommend it

- Well-tuned, fast JIT performance (5 comments): "v8 and JSC also have decades of performance tuning across basically every consumer device." ([source](https://news.ycombinator.com/item?id=49290568)) "JSC is more optimized for memory and is faster to tier up early/less overhead" ([source](https://news.ycombinator.com/item?id=47332035)) "I didn't know JavaScriptCore consistently outperformed V8" ([source](https://news.ycombinator.com/item?id=46486993))
- Proven in WebKit, iOS and macOS (3 comments): "It's used by WebKit, so it works really well and is very unlikely to disappear." ([source](https://news.ycombinator.com/item?id=47382885)) "it is certainly used in plenty of "real-world tasks" daily in iOS and macOS" ([source](https://news.ycombinator.com/item?id=46126243)) "until WebKit/JavaScriptCore shipped PTC and literally no one bat an eye" ([source](https://news.ycombinator.com/item?id=46489313))
- Default choice for embedding JavaScript (2 comments): "Reaching for an existing Javascript interpreter such as JavaScriptCore or V8 is the logical choice." ([source](https://news.ycombinator.com/item?id=48273647)) "followed closely by JavaScriptCore which is what Bun uses" ([source](https://news.ycombinator.com/item?id=46127493))
- Good at restricting JavaScript execution (2 comments): "restricts JS in all of the ways I wished I could restrict the language back when I was working on JSC" ([source](https://news.ycombinator.com/item?id=46367946)) "JavaScriptCore is super friendly to pointer capabilities" ([source](https://news.ycombinator.com/item?id=49573237))

## Alternatives hackers recommend

- [V8 JavaScript engine](https://hackerapproved.com/p/v8.md): 59 recommend
- [QuickJS](https://hackerapproved.com/p/quickjs.md): 33 recommend
- [MicroQuickJS](https://hackerapproved.com/p/microquickjs.md): 19 recommend
- [Boa JavaScript engine](https://hackerapproved.com/p/boa-javascript-engine.md): 14 recommend
- [SpiderMonkey](https://hackerapproved.com/p/spidermonkey.md): 8 recommend

## Cite as

Hacker Approved, "JavaScriptCore", https://hackerapproved.com/p/javascriptcore/ (counts from 1,795,640 Hacker News comments, November 2025 to November 2026).