Hello guixers,
For an even more foolproof experience when trying https://guix.gnu.org/cookbook/en/html_node/Reproducible-profiles.html (which already goes very smoothly), the command
`mkdir "$GUIX_EXTRA"/my-project` (fourth line) could add the option `-p` (i.e. `mkdir -p "$GUIX_EXTRA"/my-project`).

Keep hacking!

Luca

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