CoDi is a TikZ library. Its aim is making commutative diagrams easy to design, parse and tweak.
:warning: Were you looking for koDi: kommutative Diagramme für TeX
?
You're in the right place: it's the same library.
It had to be renamed due to CTAN naming restrictions.
We got your back: \usepackage{kodi}
is still supported and will produce warning messages to help you migrating. :heart:
CoDi is released under the MIT License.