TypeScript to JS

package.json

{
  "name": "hello-ts",
  "version": "1.0.0",
  "description": "Hello TS",
  "scripts": {
    "start": "node server.js",
    "gcp-build": "npm run build",
    "build": "tsc server.ts"
  },
  "author": "Steren <steren@google.com>",
  "license": "Apache-2.0",
  "dependencies": {
    "express": "^4.16.2"
  },
  "devDependencies": {
    "typescript": "^2.9.2"
  }
}

server.ts

declare var require: any
declare var process: {
  env: {
      PORT: string
  }
};

const express = require('express');

const app = express();

app.get('/', (req, res) => {
  res.send('🎉 Hello TypeScript! 🎉');
});

const server = app.listen(process.env.PORT || 8080, () => {
  const host = server.address().address;
  const port = server.address().port;

  console.log(`Example app listening at http://${host}:${port}`);
});