tsconfig.json

{
  "compilerOptions": {
    /* Basic Options */
    "target": "esnext"                        /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017','ES2018' or 'ESNEXT'. */,
    "module": "commonjs"                      /* Specify module code generation: 'none', 'commonjs', 'amd', 'system', 'umd', 'es2015', or 'ESNext'. */,
    "lib": [
      "es2017"
    ]                                         /* Specify library files to be included in the compilation. */,
    "declaration": true,                      /* Generates corresponding '.d.ts' file. */
    "sourceMap": true,                        /* Generates corresponding '.map' file. */
    "outDir": "./dist",                       /* Redirect output structure to the directory. */
    "rootDir": "./src",                       /* Specify the root directory of input files. Use to control the output directory structure with --outDir. */
    "isolatedModules": true                   /* Transpile each file as a separate module (similar to 'ts.transpileModule'). */,

    /* Strict Type-Checking Options */
    "strict": true                            /* Enable all strict type-checking options. */,
    "noImplicitAny": true,                    /* Raise error on expressions and declarations with an implied 'any' type. */
    "strictNullChecks": true,                 /* Enable strict null checks. */
    "noImplicitThis": true,                   /* Raise error on 'this' expressions with an implied 'any' type. */

    /* Additional Checks */
    "noUnusedLocals": true,                   /* Report errors on unused locals. */
    "noImplicitReturns": true,                /* Report error when not all code paths in function return a value. */

    /* Module Resolution Options */
    "moduleResolution": "node"                /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */,
    "typeRoots": [
      "./node_modules/@types",
      "./types"
    ]                                         /* List of folders to include type definitions from. */,
    // "types": []                            /* Type declaration files to be included in compilation. */,
    "allowSyntheticDefaultImports": true      /* Allow default imports from modules with no default export. This does not affect code emit, just typechecking. */,
    "esModuleInterop": true                   /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */,
    "skipLibCheck": false                     /* Skip type checking of declaration files. */,

    /* Custom */
    "forceConsistentCasingInFileNames": true  /* Disallow inconsistently-cased references to the same file. */,
    "preserveConstEnums": true                /* Do not erase const enum declarations in generated code. */,
    "resolveJsonModule": true                 /* Include modules imported with '.json' extension. Requires TypeScript version 2.9 or later. */,
  },
  "exclude": [
    "node_modules",
    "babel.config.js",
    "./dist/**/*",
    "**/*.spec.ts",
    "**/*.test.ts",
  ]
}