Boa Implemented inRustLicenceUnlicense, MIT LicenseKindopen-source software, free software, JavaScript engine
DMDScript LicenceBoost Software License, proprietary licenseKindJavaScript engineDeveloperDigital Mars
GraalJS Implemented inC, C++LicenceUniversal Permissive LicenseKindJavaScript runtime, free and open-source software, JavaScript engine
Javy Implemented inRustLicenceApache License v2.0 with LLVM ExceptionsKindcompiler, free and open-source software, toolchain, JavaScript engine
JerryScript Implemented inC99LicenceApache Software License 2.0Kindopen-source software, free software, JavaScript engine
MuJS LicenceISC licenseKindsoftware library, free software, JavaScript engineDeveloperTor Andersson, Artifex Software
Nashorn Implemented inJavaScript, JavaLicenceGPL linking exceptionKindfree and open-source software, JavaScript engine
SpiderMonkey Implemented inC, C++, RustLicenceMozilla Public License, version 2.0KindJavaScript engine
Tamarin Implemented inC++LicenceGNU Lesser General Public License, Mozilla Public License, version 2.0, GNU General Public LicenseKindvirtual machine, free software, JavaScript engine
V8 Implemented inJavaScript, C++Licence3-clause BSD LicenseKindopen-source software, application software, virtual machine, JavaScript engine