Since there are a lot of questions in the comments that might be answered by prior writing/discussions, here are a couple relevant links:
0. Trianglify.io is a GUI for my GPL-licensed node library of the same name, which is available for use in OSS projects for free: https://qrohlf.com/trianglify/
1. Trianglify (the library) first became popular because of an HN post eight years ago. Discussion here: https://news.ycombinator.com/item?id=7578002
2. I've written a short Medium article on why Trianglify.io exists and how I arrived at the current freemium/micropayments model for monetizing it: https://medium.com/@qrohlf/i-sell-triangles-on-the-internet-...