SpiderMonkey founded by Brendan Eich
SpiderMonkey is open-source JavaScript and WebAssembly engine by the Mozilla Foundation.It is the first JavaScript engine, written by Brendan Eich at Netscape Communications, and later released as open source and currently maintained by the Mozilla Foundation. It is used in the Firefox web browser.History
Eich "wrote JavaScript in ten days" in 1995,
having been "recruited to Netscape with the promise of 'doing Scheme' in the browser".
(The idea of using Scheme was abandoned when "engineering management [decided] that the language must 'look like Java'".) In late 1996, Eich, needing to "pay off [the] substantial technical debt" left from the first year, "stayed home for two weeks to rewrite Mocha as the codebase that became known as SpiderMonkey". (Mocha was the original working name for the language.)
In 2011, Eich transferred management of the SpiderMonkey code to Dave Mandelin.