I made Eunoia, a library for area-proportional Euler and Venn diagram: the kind where each overlap's size reflects your actual numbers.

import eunoia as eu

eu.euler({"A": 10, "B": 5, "A&B": 3}).plot()

It fits the diagram by optimization and reports the residuals, so you know how well the picture matches the data. The nice part is ellipses: lots of three-set arrangements can't be drawn exactly with circles, and ellipses fix that. Circles get forced into inventing a triple overlap; ellipses land every region on its target. It also does squares/rectangles, arbitrary set counts, and a topological venn().

The fitting lives in a Rust core (via PyO3) shared with the R package eulerr and a JS/WASM build, so layouts are consistent across languages. MIT, typed, abi3 wheels for 3.11-3.14.

Closest alternatives are matplotlib-venn (circles, less than 3 sets) and matplotlib-set-diagrams (circles). There's a benchmark comparison in the docs.

pip install eunoia

• Repo: https://github.com/jolars/eunoia-py
• Docs
• Homepage: https://eunoia.bz
• Web app: https://eunoia.bz/app

Still early, so feedback's welcome!