tsconfig.json

{
  "compilerOptions": {
    "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. */
    "target": "es5",                          /* 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": ["es5", "es6", "dom"],                    /* 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. */
    "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. */
    "noUnusedLocals": true,                   /* Report errors on unused locals. */
    "noImplicitReturns": true,                /* Report error when not all code paths in function return a value. */
    "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. */
    "esModuleInterop": true,                  /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */
  },
  "exclude": [ "node_modules", "tests", "types" ]
}