SpiderMonkey

SpiderMonkey is Mozilla's JavaScript engine written in C/C++. It is used in various Mozilla products, including Firefox, and is available under the MPL2.

SpiderMonkey 24 is the most recent standalone source code release. It implements JavaScript 1.8.5, and it is largely the same engine that shipped with Firefox 24. Full source code is available here: https://ftp.mozilla.org/pub/mozilla.org/js/mozjs-24.2.0.tar.bz2 (SHA1 checksum: ce779081cc11bd0c871c6f303fc4a0091cf4fe66).

The next release will be SpiderMonkey 31, around July 2014.

Documentation

SpiderMonkey Build Documentation: How to get SpiderMonkey source code, build it, and run the test suite.
Introduction to the JavaScript shell: Documentation of the command-line JavaScript shell, js.

Using SpiderMonkey

JSAPI User Guide: This guide provides an overview of SpiderMonkey and describes how you can embed engine calls in your applications to make them JavaScript-aware.
JSAPI Phrasebook: Shows the JSAPI translation of some commonly used JavaScript expressions and statements.
JSAPI Reference: SpiderMonkey API reference.
GC Rooting Guide: Guide on how to write code compatible with the Generational GC in SpiderMonkey.
JS Debugger API Guide: A user guide to the new JavaScript Debugger API introduced in Gecko 8.0 (Firefox 8.0 / Thunderbird 8.0 / SeaMonkey 2.5).
JS Debugger API Reference: API reference for the Debugger object introduced in SpiderMonkey 1.8.6, which corresponds to Gecko 8.0 (Firefox 8.0 / Thunderbird 8.0 / SeaMonkey 2.5).
How to embed the JavaScript engine: An older tutorial about embedding SpiderMonkey.

Join the SpiderMonkey users community

Choose your preferred method for joining the discussion:

Mailing list

IRC: #jsapi (learn more)
Stack Overflow: SpiderMonkey topics
Bugs?: Report them!

Hacking on SpiderMonkey

New to SpiderMonkey: A guide to hacking on SpiderMonkey.
Setting up CDT to work on SpiderMonkey: How to configure Eclipse to work on the SpiderMonkey code.

Running Automated JavaScript Tests: How to run the JavaScript test suites.
Creating JavaScript tests: How to add tests to the JavaScript test suites.

Tips, tricks and philosophy

Future Directions: Future directions for functionality, design, and coding practices.
SpiderMonkey Internals: A design overview and a file-by-file walkthrough of the implementation.
Bytecode Reference: SpiderMonkey bytecode reference.
SpiderMonkey Internals: GC: Separate internals article on the GC
SpiderMonkey Internals: Thread Safety: How SpiderMonkey's request model works inside
SpiderMonkey Internals: Hacking Tips: Collection of helpful tips & tools for hacking on the engine

Join the SpiderMonkey developers community