Simply add configuration object to module.loaders like this.
{
test: /\.uml$/,
loader: 'babel?presets[]=es2015,presets[]=react!svg-react!plantuml?format=svg'
}
- format - everything that -t plantuml.jar supports. (txt, utxt, png, svg)
- no-docker - this module use docker think/plantuml for generation svg. If you specify this option, loader will try to use local java and plantuml.jar