Where does Poetry keep its virtualenvs?

$ poetry config virtualenvs.path
/home/isme/.cache/pypoetry/virtualenvs

How much space are they taking up? (About 5% of my disk.)

$ du -sh "$(poetry config virtualenvs.path)"
7.5G	/home/isme/.cache/pypoetry/virtualenvs

How many virtualenvs do I have?

$ find "$(poetry config virtualenvs.path)" -mindepth 1 -maxdepth 1 -type d | wc -l
44

How many remain unchanged in the last 30 days? (The trick here is -mtime +30, which means last modified more than 30 days ago.)

$ find "$(poetry config virtualenvs.path)" -mindepth 1 -maxdepth 1 -type d -mtime +30 | wc -l
37

Delete them! (It uses rm -rf because the -delete action doesn’t know how to delete a folder with contents. I don’t know if find has syntax to delete the contents before deleting the folder.)

$ find "$(poetry config virtualenvs.path)" -mindepth 1 -maxdepth 1 -type d -mtime +30 -exec rm -rf {} \;

How many virtualenvs do I have now?

$ find "$(poetry config virtualenvs.path)" -mindepth 1 -maxdepth 1 -type d | wc -l
7

How much space are they taking up? About 20% of the previous amount :-)

$ du -sh "$(poetry config virtualenvs.path)"
1.4G	/home/isme/.cache/pypoetry/virtualenvs