InFile-Object lets you operate on json files just like usual objects!
npm i infile-object
const createInfileObject = require('infile-obj');
const fObj = createInfileObject('myObject.json');
fObj.name = "Hello World!";
fObj.arr = [1, 2, 3, 4];
fObj.arr.push(5);
pObj writes the updates to myObject.json
on every assignment/operation.