Your bug report

#15890: Please provide a way to delete old build directories.

which was filed against the guix package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to 15890@debbugs.gnu.org.

-- 
15890: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=15890
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