Okay so these guys built a WebAssembly based virtual machine to run x86 binaries. SO you can run ANY type of programs in the browser !

(for websites)
PHP ~ 80 %, followed by ASP.NET, Ruby and Java.

Javascript is represents only 1.5% of the backends for websites.

• 3 times faster
• with some syntactic sugar and more coherence
• the copy/paste of the virtual environment of Ruby (IRB) is now as fast as expected.
• type can be defined with RBS and TypeProf is currently a kind of type inference and generate the prototype of the signature in RBS format

Nice !