The code of the site, and the website in general, unless otherwise noted, is licensed as GNU Affero General Public License, version 3 or later.
The license itself is owned by the Free Software Foundation, not this website.

Older versions than commit c93c4c7 are licensed as MIT License.

Other content from the site, unless otherwise noted, are also licensed as Creative Commons Attribution-ShareAlike, version 4 or later,
or the GNU Free Documentation License, version 1.3 or later, with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. You may choose one or both licenses to use.

This license excludes the /novc directory which may include non-free content. These licenses all allow for forking, to create your own. Just don't make it seem as if it's by me.
Licenses for other resources in the site are listed below.
Noto Sans Font (SIL OFL 1.1)
Dacia Sandero 174819.jpg, used as a background in the window manager (CC0 1.0)
FSM Niki 650 (15007386342).jpg from Commons by FotoSleuth, CC BY 2.0
1989 FSM Niki (with Fiat badges) (18612660560).jpg from Commons by "jeremyg3030", CC BY 2.0 (Flickr says ARR now, but CC licenses can't be revoked. See here.)