The size of JavaScript frameworks and apps increases and won't stop increasing any time soon. Unfortunately, this causes large performance issues, both because the files are large and because the browser needs to spend considerable time parsing them. The JavaScript Binary AST is a new content developed by Mozilla, Bloomberg and Facebook to speed things up, both by making files smaller, and by making it much faster for your JavaScript VM to parse them – all if this without needing to minify or uglify your code, unless you want to. Let's see how it works!