This is a "meta-add-on", a library for add-on developers. This enhances the Element API and its executeJs method with the powers of the [Velocity template engine](https://velocity.apache.org). This helper library is intended to be used only temporarily, until StringTemplate based API is ready in both Java itself and Vaadin. Check the usage from the GitHub projects `src/test` directory. A real world usage example is available at [MapLibre GL integration](https://github.com/parttio/maplibre). Compared to standard `getElement().executeJs()` style API, this library provides the following benefits: * Parameter values are more readable in the JS snippets, e.g. '$foo' instead of '$0' * Possibility to pass JS objects and/or JSON to JS snippets, without transferring as string (less code, better performance). * Velocity template based JS code generation in general, e.g. generate JS code using loops and conditionals