[monocasa]

And even then, gmail wasn't really written in javascript. They compiled Java down to JavaScript because JS itself was such a pain to deal with natively.

[svachalek]

I think most of it was written for the Closure compiler (JS-to-JS), with some bits like chat windows in GWT (Java-to-JS).

[monocasa]

I was under the impression that the closure compiler didn't exist in 2004, only GWT, and that it was rewritten to be almost all JS later.

[nogridbag]

Do you have a source for this? Google did create a Java to JavaScript compiler/web framework: GWT but as far as I understood this was never used by the Gmail team. In fact, I heard there was pushback against using this on Gmail.

[cletus]

This is factually inaccurate. Gmail is and was always JavaScript. GWT had some successes (eg AdWords). Gmail wasn’t one of them.

[andykellr]

Inbox was definitely written using GWT, as were other major google products, but not gmail as far as I know.

[cletus]

That’s not true. Inbox was written in Angular originally. Not sure what it evolved to but it was always JavaScript.

[dragonshed]

Angular definitely did not catch on for google properties until much much later. Back when I did nothing but backbone/angular consulting, none of the major google properties used angular.