NCC build fails when compiling a Custom Server NextJS app - ./static.edge is not exported from react-dom

[seanjb]

Hoping someone can help as have been struggling to work around this.
I have a NextJS app that has a Custom Server (a typescript file server/index.ts transpiled to dist/index.js). The NextJS UI and server layer compile successfully and can be run without issue.

I have created a simplified copy of the repo here that demonstrates the issue. https://github.com/seanjb/nextjs-custom-server-ncc-issue
Npm scripts build and start work without issue. The package script (the NCC step) throws the error.

The Error thrown is:

Error: Module not found: Error: Package path ./server.edge is not exported from package C:\dev\test-ncc\node_modules\react-dom (see exports field in C:\dev\test-ncc\node_modules\react-dom\package.json)
Did you mean './react-dom/static.edge'?
Requests that should resolve in the current directory need to start with './'.
Requests that start with a name are treated as module requests and resolve within module directories (node_modules).
If changing the source code is not an option there is also a resolve options called 'preferRelative' which tries to resolve these kind of requests in the current directory too.

I believe this server.edge component is specific to NextJS but not part of the official react-dom package (even though it appears in their main branch).

[styfle]

If you're using Next.js, I suggest using the built-in "standalone" mode instead of trying to manually bundle with ncc.

module.exports = {
  output: 'standalone',
}

https://nextjs.org/docs/app/api-reference/next-config-js/output

This is because ncc is meant for Node.js projects and doesn't know how to bundle frontend code or RSC or many other features that are used by Next.js

[imvad]

@seanjb how did you solve it? I'm facing the same issue.

[seanjb]

Hey @imvad we ended up using rollup to package the custom server.
We use next build and standalone to package the UI, then a server build step packages the server using rollup.