If you don't need any templating languages and just need to get a simple site built plus Sass, use this as the contents of a fresh package.json:

npm start - copies src files to public and starts Browsersync server at localhost:3000
npm run build - copies files to public and autoprefixes/minifies css

One of the more difficult problems with writing systems that communicate over the network is managing input and output—that is, the reading and writing of data to and from the network and hard drive. Moving data around takes time, and scheduling it cleverly can make a big difference in how quickly a system responds to the user or to network requests.

In such programs, asynchronous programming is often helpful. It allows the program to send and receive data from and to multiple devices at the same time without complicated thread management and synchronization.