nodemon react
npm install nodemon
in your package.json add in the scripts
"command":"nodemon mainfile.js"
eg
{
"name": "abc",
"version": "0.0.1",
"description": "my server",
"scripts": {
"start": "nodemon my_file.js"
},
"devDependencies": {
"nodemon": "~1.3.8",
},
"dependencies": {
}
}