A [[Java]] web framework. First released in 2006. [Wikipedia](https://en.wikipedia.org/wiki/Google_Web_Toolkit),
Out of the "JavaScript contenders", I am most familiar with GWT. It was the most ambitious endeavor as it tried to re-implement everything - Programming Language ([[Java]]), RPC mechanism, UI framework, so on.
This didn't span out well:
* **Unergonomic Developer Experience** - It heavily depended on an IDE plugin ([[IDEs|Eclipse]] plugin). Even then, the development experience was not good (I remember full compilations of a *Hello World* taking 60 seconds).
* **UI paradigm's rapid change** - see [[Leaky Abstraction#Ruby on Rails *wannabes*]].
* GWT's "compile to N target"... became less relevant as the modern web browsers replaced IE6 - see [[FE Framework History#Cross-browser compatibility]]
The most enduring technology of the GWT is the Java-to-Javascript [[Transcompilers]]. This allowed the reuse of Java business logic in JavaScript. The modern trend is the opposite ([[React Native]]) as it's much more reliable to embed a JavaScript runtime.