tsconfig.json

{
  // This attribute will hold all the compile option of TypeScript
  "compilerOptions": {
    // Where are located your source code
    "rootDir": "src",

    // Where you want to put our compiled code
    "outDir": "build",

    // Which ES library you want to include
    // If the project will be used as a server, no browser, then use the esnext or one of the last version)
    // Otherwise, you I advice using ES6 but you still can use an advance ES version
    // If you omit the option it will use
    // For --target ES5: DOM,ES5,ScriptHost
    // For --target ES6: DOM,ES6,DOM.Iterable,ScriptHost
    "lib": ["es2018"],

    // Which ES version you want to target during compilation, this is reliable to the `lib` option
    // This options is really important regarding the project usage too (back or front)
    // Put ES5 if you need to IE compatibility, otherwise you can target at least es2017 or es2018
    // Tip: Take a look at this here if you need to know which feature is available depending of your Node version
    // @see https://node.green
    "target": "es2018",

    // Depends how you want to resolve your module, TypeScript tends to use the `classic` way but let's
    // stick with the `node` one
    // @see https://www.typescriptlang.org/docs/handbook/module-resolution.html
    "moduleResolution": "node",

    // From documentation, Specify module code generation
    // commonjs === (target = ES3 OR ES5)
    // Otherwise use es6
    // Fixes "The ESM Module Loader is Experimental" Error
    "module": "commonjs",

    // Sourcemap is usefull for the debugging part
    // During dev you should active this one and then disable it in production
    "sourceMap": true,

    // Reolve `.json`file without tricking with a custom and bad json.d.ts file
    "resolveJsonModule": true,

    // Allow to import node module without `import *`
    // Ex import express from 'express'
    "esModuleInterop": true,

    // don't produce comments in out directory
    "removeComments": true,

    // WARNING will not produce js if there are errors in code
    "noEmitOnError": true
  },

  // The folder or files you want to exclude
  // You can also use regex `**/*.spec.ts` for ex
  "exclude":[
    "node_modules",
    "build"
  ]
}