"Error while requesting resource" with `next/font/google` using `next dev --turbopack`

[jorupp]

Link to the code that reproduces this issue

https://github.com/jorupp/next-font-error-turbopack

To Reproduce

Using a computer configured with a MITM HTTPS proxy (ie. a corporate security tool):

1. Start the application (next dev)
2. Go to http://localhost:3000/

Current vs. Expected behavior

Expected: page renders with google font
Actual: error.

 ⨯ [next]/internal/font/google/geist_e531dabc.module.css:8:9
Module not found: Can't resolve '@vercel/turbopack-next/internal/font/google/font'
   6 |   font-display: swap;
   7 |   src: url(@vercel/turbopack-next/internal/font/google/font?{%22url%22:%22https://fonts.gstatic.com/s/geist/v1/gyByhwUxId8gMEwSGFWNOITddY4.woff2%22,%22preload%22:false,%22has_size_adjust%22:true}) format('woff2');
>  8 |   unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C0, U+2113, U+2C60-2C7F, U+A720-A7FF;
     |         ^
   9 | }
  10 | /* latin */
  11 | @font-face {

Import map: Resolved by import map

https://nextjs.org/docs/messages/module-not-found


 ⚠ [next]/internal/font/google/gyByhwUxId8gMEwSGFWNOITddY4-s.woff2
Error while requesting resource
There was an issue establishing a connection while requesting https://fonts.gstatic.com/s/geist/v1/gyByhwUxId8gMEwSGFWNOITddY4.woff2.

Provide environment information

Operating System:
  Platform: win32
  Arch: x64
  Version: Windows 10 Enterprise
  Available memory (MB): 65234
  Available CPU cores: 20
Binaries:
  Node: 22.13.1
  npm: 10.9.2
  Yarn: N/A
  pnpm: N/A
Relevant Packages:
  next: 15.4.0-canary.6 // Latest available version is detected (15.4.0-canary.6).
  eslint-config-next: N/A
  react: 19.1.0
  react-dom: 19.1.0
  typescript: 5.8.3
Next.js Config:
  output: N/A

Which area(s) are affected? (Select all that apply)

Turbopack

Which stage(s) are affected? (Select all that apply)

next dev (local)

Additional context

This only happens if the corporate MITM security proxy is enabled. I'm reasonably certain this isn't a next or turbopack bug, but I can't figure out what environment variable(s) to set to give turbopack/rust the list of certificates to trust (or to tell it to use my system's trusted CA list). NODE_EXTRA_CA_CERTS and SSL_CERT_FILE cover most of the other tools I work with, but I can't figure out how to tell turbopack about the additional CA cert to trust.

[timneutkens]

The fetch is instantiated here:

next.js/turbopack/crates/turbo-tasks-fetch/src/lib.rs

Line 61 in d96ecdf

let client_builder = reqwest::Client::builder();

Seems reqwest does not have such an env var and something would have to be implemented for it: seanmonstar/reqwest#15. Maybe you could investigate this further and send a PR?

[CodeMan62]

let me try to investigate and send a PR will it okay @timneutkens

[jorupp]

Ah, thanks for the pointer @timneutkens - I was having trouble finding the origination of the call to figure out what variables that might support to provide custom CAs (or a variable I could set to tell it to use the system CAs on windows).

[imrvon]

Same problem. Not sure why.

Edit by maintainer bot: Comment was automatically minimized because it was considered unhelpful. (If you think this was by mistake, let us know). Please only comment if it adds context to the issue. If you want to express that you have the same problem, use the upvote 👍 on the issue description or subscribe to the issue for updates. Thanks!

[Joshua-hypt]

This feature seems to be broken more than ever

[timneutkens]

@Joshua-hypt I'd love to investigate whatever you're running into but can't do much when the comment is not constructive feedback.

NODE_EXTRA_CA_CERTS and SSL_CERT_FILE have never been supported officially, they're specific to the Node.js runtime, not Next.js internals. Not unexpected that these won't work when the bundler now runs in Rust.

[CodeMan62]

@timneutkens the PR i created was that good or if there is anything else i can do here in it i'd love to work on it

[restoker]

this bug is alive currently
Module not found: Can't resolve '@vercel/turbopack-next/internal/font/google/font'
src: url(@vercel/turbopack-next/internal/font/google/font?{%22url%22:%22https://fonts.gstatic.com/s/geistmono/v3/or3nQ6H-1_WfwkMZI_qYFrkdmhHkjkotbA.woff2%22,%22preload%22:false,%22has_size_adjust%22:true}) format('woff2');

17 | unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C0, U+2113, U+2C60-2C7F, U+A720-A7FF;

nextjs version: 15.3.2

[BKR-dev]

same issue when running the learning tutorial from https://nextjs.org/learn/dashboard-app and compiling on another machine

[gavan-x]

Confirmed and tested from 15.3.5 to 15.4.1 is where it brakes for me.
If you guys keep aggressively pushing untested updates, you're only opening the door for devs to switch to alternative framework.

[bgw]

I believe there's two issues potentially being a little mixed up here:

• The MITM HTTPS proxy issue now has an experimental option on recent canary releases: Turbopack rustls-tls fails to recognize system keychain certs #79059 and Turbopack: Add an option to use system TLS certificates (fixes #79060, fixes #79059) #81818 . We may make this the default in the future, but not until an upstream issue in the reqwest library is resolved. This experimental feature should be available with the stable Next 16 release.

• @gavan1 I believe your issue is Failed to get Google fonts #81697 . That was root-caused to a Rustc / LLVM miscompilation bug on Intel macos. It did not impact ARM machines, which is why we didn't catch it in our own testing. It should be fixed in v15.4.4. Sorry about that!

Since both of these issues should now be resolved, I'm closing this issue. If you run into any more problems with Google Fonts or the new option for using system CA certificates, please feel free to open a new issue!