An ECMAScript engine is a program that executes source code written in a version of the ECMAScript language standard, for example, JavaScript.
These are new generation ECMAScript engines for web browsers, all implementing just-in-time compilation (JIT) or variations of that idea. The performance benefits for just-in-time compilation make it much more suitable for web applications written in JavaScript.
SpiderMonkey: A JavaScript engine in Mozilla Gecko applications, including Firefox. The engine currently includes the IonMonkey and JägerMonkey compilers, has previously included the TraceMonkey compiler (first javascript JIT), and is planned to include the forthcoming OdinMonkey compiler.
The following engines use runtime interpreters, which do not compile into native machine code and generally run more slowly.
Continuum:[7] A self-interpreter that supports recent iterations of the draft ECMAScript 6 specification.[8] Uniquely, the engine is implemented in ECMAScript 3, which makes it possible to run ES6 in browsers as old as IE6.[9]
Futhark: The ECMAScript engine of the Opera web browser versions 9.50 to 10.10.
KJS: The engine used in Konqueror, and one component of KHTML, a predecessor to JavaScriptCore.
Linear B: The ECMAScript engine of the Opera web browser versions 7.0 to 9.50, exclusive.
Narcissus: JavaScript implemented in JavaScript (a meta-circular evaluator), intended to run in another JavaScript engine, of theoretical and educational nature only.
JS-Interpreter A lightweight JavaScript interpreter implemented in JavaScript with step-by-step execution.
QtScript: Originally developed by Trolltech, now owned by Digia. It provides QObject integration with JavaScriptCore.
YAJI: An ECMAScript engine[10] based on the FESI[11] implementation by Jean-Marc Lugrin in 1999, using the Java platform, currently being developed to support the latest standards (Spec 262, v5.1).[12]
Duktape: a small footprint, easily embeddable Ecmascript E5/E5.1 engine.[13]
The Kinoma Platform, an ECMAScript 5 runtime environment and framework
Jsish: a javascript interpreter with builtin sqlite, json, websocket, and zvfs support.[14]
Websocket.js: embeddable Javascript engine with HTTP/Websocket support.[15]
Espruino: a very small footprint interpreter specifically for Microcontrollers. Can run in less than 8kB of RAM by executing from source (rather than Bytecode)
MuJS: a lightweight ECMAScript interpreter library, designed for embedding in other software to extend them with scripting capabilities. Originally developed for MuPDF.[16]
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