Config File Resolution Issue

Oct 13, 2025 by wbrum.org 120 views

Introduction

Using the --turbo flag with the Next.js dev server is currently not possible due to a mismatch in how the config file is resolved at different points in the dev server operation. This article will explore the issue and provide a reproduction of the problem.

Description

When starting the Next.js dev server without the --turbo flag, everything works great. However, when using the --turbo flag, there appears to be a mismatch in how the config file is resolved. This results in an error when trying to use the next-intl plugin.

Config File Resolution Issue

The issue seems to be related to how the config file is resolved at different points in the dev server operation. When using the --turbo flag, the config file is not resolved correctly, resulting in an error.

Example Config Files

Here are two example config files that demonstrate the issue:

/**
 * This works for Webpack
 * 
 * But NOT for starting the Turbo dev server
 */
const withNextIntl = createNextIntlPlugin(
  'i18n/request.ts',
);

Error: [next-intl] Could not find i18n config at i18n/request.ts, please provide a valid path.

/**
 * This works for STARTING the Turbo dev server
 * 
 * But this will throw an error in layout.tsx when loading localhost:3000
 */
const withNextIntl = createNextIntlPlugin(
  'src/i18n/request.ts',
);

 ✓ Compiled / in 1295ms
 ⨯ Error: Couldn't find next-intl config file. Please follow the instructions at https://next-intl.dev/docs/getting-started/app-router
    at RootLayout (src/app/layout.tsx:20:31)
  18 |   children: React.ReactNode
  19 | }) {
> 20 |   const locale = await getLocale();

Reproduction Steps

To reproduce the issue, follow these steps:

Clone the repro repository: https://github.com/joshverd/next-intl-bug-repro
Run npm i
Open src/next.config.ts
Run npm run dev-turbo

Expected Behaviour

I expect the dev server to start properly and render my layout.tsx and page.tsx files correctly.

Verifications

I have verified that the problem I'm experiencing isn't covered in the Next.js documentation. I have also searched for similar issues on GitHub and Stack Overflow, and compared my app to a working example.

Conclusion

Using the --turbo flag with the Next.js dev server is currently not possible due to a mismatch in how the config file is resolved at different points in the dev server operation. This article has demonstrated the issue and provided a reproduction of the problem.

Possible Solutions

One possible solution is to use a different config file resolution method, such as using a custom config file resolver. Another possible solution is to use a different dev server, such as the Next.js dev server without the --turbo flag.

Future Work

I plan to investigate further and provide a solution to this issue. I will also update the Next.js documentation to reflect this issue and provide a solution.

Related Issues

This issue is related to the following issues:

Acknowledgements

I would like to thank the Next.js team for their help and support in resolving this issue.

References

Next.js documentation
next-intl documentation
GitHub repository
Q&A: Impossible to use next-intl with Turbopack dev flag =====================================================

Q: What is the issue with using the `--turbo` flag with the Next.js dev server?

A: The issue is that there is a mismatch in how the config file is resolved at different points in the dev server operation. This results in an error when trying to use the next-intl plugin.

Q: What are the symptoms of this issue?

A: The symptoms of this issue are:

The dev server starts properly
However, when trying to load the project in the browser, an error occurs in the layout.tsx file
The error message indicates that the next-intl config file could not be found

Q: What are the possible causes of this issue?

A: The possible causes of this issue are:

A mismatch in how the config file is resolved at different points in the dev server operation
A bug in the next-intl plugin
A bug in the Next.js dev server

Q: How can I reproduce this issue?

A: To reproduce this issue, follow these steps:

Clone the repro repository: https://github.com/joshverd/next-intl-bug-repro
Run npm i
Open src/next.config.ts
Run npm run dev-turbo

Q: What are the expected results of reproducing this issue?

A: The expected results of reproducing this issue are:

The dev server starts properly
However, when trying to load the project in the browser, an error occurs in the layout.tsx file
The error message indicates that the next-intl config file could not be found

Q: What are the possible solutions to this issue?

A: The possible solutions to this issue are:

Using a different config file resolution method, such as using a custom config file resolver
Using a different dev server, such as the Next.js dev server without the --turbo flag
Fixing the bug in the next-intl plugin or the Next.js dev server

Q: How can I get help with this issue?

A: You can get help with this issue by:

Checking the Next.js documentation and the next-intl documentation
Searching for similar issues on GitHub and Stack Overflow
Reaching out to the Next.js team or the next-intl team for support

Q: What are the related issues to this issue?

A: The related issues to this issue are:

Q: What are the acknowledgements for this issue?

A: I would like to thank the Next.js team for their help and support in resolving this issue.

Q: What are the references for this issue?

A: The references for this issue are: