*[[JavaScript:SpiderMonkey:RegExp API|Expose ECMA 262 Regular Expression API]] to C/C++ clients.
*A [[JavaScript:SpiderMonkey:Parser API|new SpiderMonkey API]] for building and inspecting parse trees.
*Narcissus meta-circular JavaScript interpreter ([httphttps://lxrgithub.mozilla.orgcom/mozilla/source/js/narcissus source code]).
*[[JS engine modularization]]: incremental long-term project to modularize JS engine source code.