Description

OpenNext takes the Next.js build output and converts it into packages that can be deployed across a variety of environments. Natively OpenNext has support for AWS Lambda, and classic Node.js Server.

Features

OpenNext aims to support all Next.js 14 features. Some features are work in progress. If you are running into any problems make sure to check the docs first before you open a new issue or visit our Discord to let us know!

• [x] App & Pages Router
• [x] API routes
• [x] Dynamic routes
• [x] Static site generation (SSG)
• [x] Server-side rendering (SSR)
• [x] Incremental static regeneration (ISR)
• [x] Middleware
• [x] Server actions
• [x] Image optimization
• [x] NextAuth.js
• [x] Running at edge
• [x] Almost no coldstart (*)

Who is using OpenNext?

Gymshark UK, Udacity, TUDN, NHS England

Example

In the example folder, you can find a Next.js benchmark app. It contains a variety of pages that each test a single Next.js feature. The app is deployed to both Vercel and AWS using SST.

AWS link: https://d1gwt3w78t4dm3.cloudfront.net

Vercel link: https://open-next.vercel.app

Configuration

Configuration file

For personalisation you need to create a file open-next.config.ts at the same place as your next.config.js, and export a default object that satisfies the OpenNextConfig interface. It is possible to not have an open-next.config.ts file, the default configuration will then be applied automatically.

Debug mode

OpenNext can be executed in debug mode by setting the environment variable OPEN_NEXT_DEBUG=true before your build.

This will output A LOT of additional logs to the console. This also disable minifying in esbuild, and add source maps to the output. This can result in code that might be up to 2-3X larger than the production build. Do not enable this in production.

You can read more about the configuration in the docs

Contribute

To run OpenNext locally:

1. Clone this repository.
2. Build open-next:

   cd packages/open-next
   pnpm build

3. Run open-next in watch mode:

   pnpm dev

4. Now, you can make changes in open-next and build your Next.js app to test the changes.

   cd path/to/my/nextjs/app
   path/to/open-next/packages/open-next/dist/index.js build

Coldstart

OpenNext provide you with a warmer function that can be used to reduce cold start.

On Lambda, there are multiple scenarios where a lambda will trigger a cold start even if you have some warmed instance. For example if you have more requests than warm instances you'll get a cold start. Also NextJs lazy load the routes, so even if you hit a warm instance, this specific route might not have been loaded yet.

Acknowledgements

We are grateful for the projects that inspired OpenNext and the amazing tools and libraries developed by the community:

• nextjs-lambda by Jan for serving as inspiration for packaging Next.js's standalone output to Lambda.
• CDK NextJS by JetBridge for its contribution to the deployment architecture of a Next.js application on AWS.
• serverless-http by Doug Moscrop for developing an excellent library for transforming AWS Lambda events and responses.
• serverless-nextjs by Serverless Framework for paving the way for serverless Next.js applications on AWS.

Special shoutout to @khuezy and @conico974 for their outstanding contributions to the project.

Maintained by SST. Join our community: Discord | YouTube | Twitter