Error: ENOENT: no such file or directory, lstat '/vercel/path0/.next/export-detail.json'

[timber river]

I am trying to deploy my repo to Vercel and I got this error at the end of the build log which doesn't provide me any more details:
Error: ENOENT: no such file or directory, lstat '/vercel/path0/.next/export-detail.json'

I had a similar situation with this reddit post but this didn't work either (update):
https://www.reddit.com/r/nextjs/comments/1bkswd8/enoent_no_such_file_or_directory_lstat/

Any reason why this is happening?
This is my repo:
https://github.com/ubergonmx/porum-nextjs

[strong hearth]

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[exotic sable]

This error indicates a missing file export-detail.json in .next directory. This issue typically arises during the static export process when Vercel expects certain files to exist but they haven't been generated or are missing.

[timber river]

How do I fix this? It doesn't generate export-detail.json even if I run npm run build locally

[exotic sable]

Start another project and copy all your folders

[timber river]

Done, still the same error

[exotic sable]

can u show more logs?

[timber river]

Here's the complete logs

[timber river]

I don't know what to get from these logs, the error doesn't make any sense to me.

[timber river]

I found the issue and that is import { writeFile as fsWriteFile } from "fs/promises"; in my server actions file.

For more context, I had the following:

let url: string | undefined;
if (avatar) {
  if (env.STORAGE === "local") {
    url = `${Date.now()}-${generateIdFromEntropySize(5)}-${avatar.name.replaceAll(" ", "_")}`;
    const buffer = Buffer.from(await avatar.arrayBuffer());
    const fullPath = process.cwd() + "/" + env.LOCAL_AVATAR_PATH + url;
    await fsWriteFile(fullPath, buffer);

    console.log("[SIGNUP] Avatar saved to", fullPath);
  } else if (env.STORAGE === "online") {
    const [res] = await uploadFiles("avatar", {
      files: [avatar],
    });
    url = res.url;
  }
}

Reason is that you can't write files in Serverless Functions because the file system is ephemeral.
I commented it when deploying, only added a note to uncomment it if they want to test locally the avatar saving.
Sources:

• https://github.com/orgs/vercel/discussions/241#discussioncomment-363002
• https://www.reddit.com/r/nextjs/comments/zo5ez3/creating_a_file_using_fs_on_vercel/