tsconfig.json

{
  "compilerOptions": {
    "module": "esnext",
    // Target latest version of ECMAScript.

    // We don't use tsc for compiling ts code into js, instead we use babel-node for running APIs, so target won't make any differences
    "target": "es2017",
    // Search under node_modules for non-relative imports.
    "moduleResolution": "node",
    // Process & infer types from .js files.
    "allowJs": false,
    // Don't emit; allow Babel to transform files.
    "noEmit": true,
    // Enable strictest settings like strictNullChecks & noImplicitAny.
    "strict": true,
    // Disallow features that require cross-file information for emit.
    "isolatedModules": false,
    // Import non-ES modules as default imports.
    "esModuleInterop": true,
    // Enable strict null checks
    "strictNullChecks": false,
    "skipLibCheck": true
  },
  "include": ["**/*.ts"],
  "exclude": [".serverless", ".webpack", "node_modules"]
}