nx/docs/shared/recipes/add-stack/add-express.md

title	description
Add a New Express Project	Learn how to create and configure Express applications and libraries in your Nx workspace using the @nx/express plugin.

Add a New Express Project

Supported Features

Because we are using an Nx plugin for Express, all the features of Nx are available.

{% pill url="/features/run-tasks" %}✅ Run Tasks{% /pill %} {% pill url="/features/cache-task-results" %}✅ Cache Task Results{% /pill %} {% pill url="/ci/features/remote-cache" %}✅ Share Your Cache{% /pill %} {% pill url="/features/explore-graph" %}✅ Explore the Graph{% /pill %} {% pill url="/ci/features/distribute-task-execution" %}✅ Distribute Task Execution{% /pill %} {% pill url="/getting-started/editor-setup" %}✅ Integrate with Editors{% /pill %} {% pill url="/features/automate-updating-dependencies" %}✅ Automate Updating Nx{% /pill %} {% pill url="/features/enforce-module-boundaries" %}✅ Enforce Module Boundaries{% /pill %} {% pill url="/features/generate-code" %}✅ Use Code Generators{% /pill %} {% pill url="/features/automate-updating-dependencies" %}✅ Automate Updating Framework Dependencies{% /pill %}

Install the Express Plugin

{% callout type="note" title="Keep Nx Package Versions In Sync" %} Make sure to install the @nx/express version that matches the version of nx in your repository. If the version numbers get out of sync, you can encounter some difficult to debug errors. You can fix Nx version mismatches with this recipe. {% /callout %}

nx add @nx/express

Create an Application

Use the app generator to create a new Express app.

nx g @nx/express:app apps/my-express-api

Serve the API by running

nx serve my-express-api

This starts the application on localhost:3333/api by default.

Create a Library

The @nx/express plugin does not have a library generator, but we can use the library generator from the @nx/js plugin. To create a new library, install the @nx/js package and run:

nx g @nx/js:lib libs/my-lib

Once the library is created, update the following files.

export function someFunction(): string {
  return 'some function';
}

/**
 * This is not a production server yet!
 * This is only a minimal backend to get started.
 */

import express from 'express';
import * as path from 'path';
import { someFunction } from '@my-express-app/my-lib';

const app = express();

app.use('/assets', express.static(path.join(__dirname, 'assets')));

app.get('/api', (req, res) => {
  res.send({ message: `Welcome to my-express-app! ${someFunction()}` });
});

const port = process.env.PORT || 3333;
const server = app.listen(port, () => {
  console.log(`Listening at http://localhost:${port}/api`);
});
server.on('error', console.error);

Now when you serve your API, you'll see the content from the library being displayed.

More Documentation

• @nx/express
• @nx/js
• Express