lkarow / example-express-api-vercel

How to deploy an Express API to Vercel

Deploy an Express API to Vercel

Create a Vercel account

Sign up for a free Vercel account and give Vercel access to your repository.

Create an Express API (or use an existing one)

Below and in this repository is a basic example of an API built with Node.js and Express.

const express = require('express');
const app = express();
const port = 3000;

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

app.listen(port, () => {
  console.log(`App listening on port ${port}`);
});

module.exports = app;

Export the app

Vercel will convert the Express app into a serverless function. To do this, you need to export the Express API. All it takes is one line of code:

module.exports = app;

Create a vercel.json file

Next, create a vercel.json file in the root directory of the project. Vercel needs this configuration file to create the Express API and deploy it as a serverless function.

{
  "version": 2,
  "builds": [
    {
      "src": "index.js",
      "use": "@now/node"
    }
  ],
  "routes": [
    {
      "src": "/(.*)",
      "dest": "/"
    }
  ]
}

Push everything to your repository

Deploy the app to Vercel

In your Vercel Dashboard, click the Add new... button and then select Project. Import your repository from GitHub, GitLab or Bitbucket. On the next screen, you can further configure the project (e.g. set environment variables). Finally, click on Deploy and you're done.