I add [index.js](https://github.com/zcreativelabs/react-simple-maps/blob/master/examples/country-map/pages/index.js) , [ch-with-cantons.json](https://github.com/zcreativelabs/react-simple-maps/blob/master/examples/country-map/static/ch-with-cantons.json?short_path=1e97833) and other dependencies : `"next": "^5.1.0", "react-simple-maps": "~0.12.0" ` in package.json but there is a problem  