Turbopack build error: formatMetadataHeaders causes Turbopack build failure in Next.js 16 canary

[namodynamic]

Hi! 👋

Firstly, thanks for your work on this project! 🙂

Today I used patch-package to patch @clerk/nextjs@6.36.2 for the project I'm working on.

When building with Next.js 16.1.0-canary.21 and Turbopack enabled, the build fails because formatMetadataHeaders in keyless-custom-headers.js is not recognized as an async function. Making it async resolves the issue.

Here is the diff that solved my problem:

diff --git a/node_modules/@clerk/nextjs/dist/esm/server/keyless-custom-headers.js b/node_modules/@clerk/nextjs/dist/esm/server/keyless-custom-headers.js
index 11ccc7a..8994dad 100644
--- a/node_modules/@clerk/nextjs/dist/esm/server/keyless-custom-headers.js
+++ b/node_modules/@clerk/nextjs/dist/esm/server/keyless-custom-headers.js
@@ -67,7 +67,7 @@ function getNextVersion() {
     return void 0;
   }
 }
-function formatMetadataHeaders(metadata) {
+async function formatMetadataHeaders(metadata) {
   const headers2 = new Headers();
   if (metadata.nodeVersion) {
     headers2.set("Clerk-Node-Version", metadata.nodeVersion);

This issue body was partially generated by patch-package.

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[jacekradko]

Thanks for filing the issue @namodynamic . This has been addressed here: #7445