...It uses a watcher to determine when files change, to only lint files as necessary. It also has a CI mode where it does not set up a daemon and just lints in parallel. In order to use esprint, first place an .esprintrc file in the root directory your project. This is similar to a .flowconfig if you use flow types. The .esprintrc file describes which paths to lint and which paths to ignore. You can also override the port to start the background server on. esprint will find the root of your project automatically and lint the whole project. In default mode, esprint will start a background server to watch source files and cache lint results in memory.