Problem: Node Sass does not yet support your current environment

ionic serve
Error: Node Sass does not yet support your current environment: OS X 64-bit with Unsupported runtime (64)
For more information on which environments are supported please see:
https://github.com/sass/node-sass/releases/tag/v4.7.2
at module.exports (/Users/ralfweinbrecher/Development/Coursera/Ionic/confusion-ionic/node_modules/node-sass/lib/binding.js:13:13)
at Object.<anonymous> (/Users/ralfweinbrecher/Development/Coursera/Ionic/confusion-ionic/node_modules/node-sass/lib/index.js:14:35)
at Module._compile (internal/modules/cjs/loader.js:702:30)
at Object.Module._extensions..js (internal/modules/cjs/loader.js:713:10)
at Module.load (internal/modules/cjs/loader.js:612:32)
at tryModuleLoad (internal/modules/cjs/loader.js:551:12)
at Function.Module._load (internal/modules/cjs/loader.js:543:3)
at Module.require (internal/modules/cjs/loader.js:650:17)
at require (internal/modules/cjs/helpers.js:20:18)
at Object.<anonymous> (/Users/ralfweinbrecher/Development/Coursera/Ionic/confusion-ionic/node_modules/@ionic/app-scripts/dist/core/bundle-components.js:6:16)

Einfache Lösung:

npm rebuild node-sass