Alright context for the non french here:

"Système D" is an shortening of "Système débrouille", which roughly means "DIY system".

It's used to say that you had to come up with a solution to your problem yourself.

systemctl --user enable --now clicker.timer for a clicker sound every 15 minutes

Sudo systemctl enable --now woodworking

systemctl start heating

Now that I think about it, I'm sure there is someone somewhere who has this setup.