bug: next-auth module completely broken with MODULE_NOT_FOUND next/server.js when doing folder structure instead of app

[marcomnrq]

Provide environment information

Happening in the latest version available: create-t3-app@7.38.1.

Describe the bug

On public and protected routes, the tRPC calls made from the client fail indicating the following error:

 Error: Failed to load external module next-auth: Error [ERR_MODULE_NOT_FOUND]: Cannot find module '/Users/marcomnrq/VSCode Projects/examplebug/node_modules/next/server' imported from /Users/marcomnrq/VSCode Projects/examplebug/node_modules/next-auth/lib/env.js
Did you mean to import "next/server.js"?

Reproduction repo

n/a

To reproduce

Create a new app using the following settings.

Start the app with npm run dev and see the console / logs.

Additional information

Happy to help debugging this further, but i think it has to do with the import in this file. Will try to post some findings in this issue.

[marcomnrq]

This looks to be related > vercel/next.js#64529

[visheshd]

Getting this with our codebase as well. Just tried to update to the latest t3-boilerplate.

[BrentonBeltrami]

This is related/duplicate of #2027.
I am also getting this error.

[ari-party]

nextauthjs/next-auth#9385 (comment)

[timmatsam]

Also getting this error - I feel as if it wasn't prudent to update next-auth to the beta version - i'm a bit surprised a non stable version was approved into the t3 app? Was playing around with this to no avail, mapping next-auth to the transpilePackages option in the next config file did not fix it for me as per ari-party's reference. Best thing to do is to use the 7.37.0 version until a fix has been implemented.

[jakerich1]

This worked for me nextauthjs/next-auth#10058 (comment)

[lfnb]

I encountered the same issue and attempted the following solutions to resolve it:

1. Downgraded t3-app: pnpm create t3-app@7.38.0, ❌
2. Downgraded next-auth, ❌
3. Changed the page route to an app route, ✅

[nbibler]

Simplest "fix" for this I've currently seen is to modify next.config.js and restart the next dev server:

diff --git a/next.config.js b/next.config.js
index 080cc56..a5c18b9 100644
--- a/next.config.js
+++ b/next.config.js
@@ -17,6 +17,8 @@ const config = {
     locales: ["en"],
     defaultLocale: "en",
   },
+
+  transpilePackages: ["next-auth"],
 };
 
 export default config;

From nextauthjs/next-auth#9385 (comment).

This appears to work as expected with:

├── @auth/prisma-adapter@2.8.0
├── next-auth@5.0.0-beta.25
├── next@15.2.4
├── react-dom@19.1.0
├── react@19.1.0
├── superjson@2.2.2
└── zod@3.24.2