Volto fails to start if we use a custom TMPDIR

[thet]

Describe the bug

When starting the Volto 18.32.1 release it fails with the following error:

webpack 5.90.1 compiled successfully in 12708 ms
sswp> Handling Hot Module Reloading
Cannot find module '@root/config'
Require stack:
- /home/_thet/data/dev/plone/volto-18/packages/volto/build/server.js
    at Function._resolveFilename (node:internal/modules/cjs/loader:1401:15)
    at defaultResolveImpl (node:internal/modules/cjs/loader:1057:19)
    at resolveForCJSWithHooks (node:internal/modules/cjs/loader:1062:22)
    at Function._load (node:internal/modules/cjs/loader:1211:37)
    at TracingChannel.traceSync (node:diagnostics_channel:322:14)
    at wrapModuleLoad (node:internal/modules/cjs/loader:235:24)
    at Module.require (node:internal/modules/cjs/loader:1487:12)
    at require (node:internal/modules/helpers:135:16)
    at Module.../../../../../../../thet/tmp/tmp-227960-TkQC4Qa2kSF9-.js (/home/_thet/data/dev/plone/volto-18/packages/volto/build/thet/tmp/tmp-227960-TkQC4Qa2kSF9-.js:7:1)
    at __webpack_require__ (/home/_thet/data/dev/plone/volto-18/packages/volto/@plone/volto/webpack/bootstrap:24:1)
sswp> !!! Script exited with code 1

I first saw this when using uvx cookieplone project but it happens also with a source checkout of Volto 18.32.1.

On the Volto main branch, I do not encounter this problem.

To Reproduce
Steps to reproduce the behavior:

# Put in .bashprofile: export TMPDIR=~/tmp
git clone git@github.com:plone/volto.git -b 18.32.1 volto-18.32.1
cd volto-18.32.1
make install
make start

Expected behavior

make start starting volto without an error.

Software (please complete the following information):

• OS: Linux Debian testing.

$ uname -a
Linux thes 6.18.5+deb14-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.18.5-1 (2026-01-16) x86_64 GNU/Linux

• Volto Version: 18.32.1, 18.32.0, 18.4.0
• Node version: v22.15.0

[wesleybl]

I couldn't simulate that error, and it doesn't occur in CI either. Could you provide more details?

[thet]

Not sure, which other info I can share. @wesleybl can you give me your node version and OS version information?
On my side, this path from the error message looks strange: /home/_thet/data/dev/plone/volto-18/packages/volto/build/thet/tmp/tmp-227960-TkQC4Qa2kSF9-.js - it contains thet/tmp from within a build directory. I have this in my .bashprofile: export TMPDIR=~/tmp. Maybe it's related...

[thet]

@wesleybl actually that was it!

When starting Volto with the default TMPDIR, which is /tmp, then the error doesn't occur.

This is how I could start Volto without the mentioned error:

TMPDIR=/tmp make start

Could still be a bug in Volto or in a 3rd party dependency.

[wesleybl]

@thet Here, even with export TMPDIR=~/tmp in .bashrc, it works.