tsconfig.json

{
  "compilerOptions": {
    "module": "ESNext", // use the latest ECMA/JavaScript syntax for our import statements and such
    "target": "ES2021", // choose our ECMA/JavaScript version (all modern browsers support ES6 so it's your best bet)
    // "lib": [
    //   // choose our default ECMA/libraries to import
    //   "dom", // mandatory for all browser-based apps
    //   "es6" // mandatory for targeting ES6
    // ],
    "useDefineForClassFields": true, // enable latest ECMA runtime behavior with older ECMA/JavaScript versions (delete this line if target: "ESNext" or "ES2022"+)
    "moduleResolution": "node", // ensures we are using CommonJS for our npm packages
    "noResolve": false, // disable TypeScript from automatically detecting/adding files based on import statements and etc (it's less helpful than you think)
    "isolatedModules": true, // allows our code to be processed by other transpilers, such as preventing non-module TS files (you could delete this since we're only using base TypeScript)
    "removeComments": true, // remove comments from our outputted code to save on space (look into terser if you want to protect the outputted JS even more)
    "esModuleInterop": true, // treats non-ES6 modules separately from ES6 modules (helpful if module: "ESNext")
    "noImplicitAny": false, // usually prevents code from using "any" type fallbacks to prevent untraceable JS errors, but we'll need this disabled for our example code
    "noUnusedLocals": false, // usually raises an error for any unused local variables, but we'll need this disabled for our example code
    "noUnusedParameters": true, // raises an error for unused parameters
    "noImplicitReturns": true, // raises an error for functions that return nothing
    "skipLibCheck": true // skip type-checking of .d.ts files (it speeds up transpiling)
  },
  "include": ["src"] // specify location(s) of .ts files
}