Flowy
The minimal javascript library to create flowcharts
...The library focuses on simplicity and aesthetics, offering a clean look out of the box that can be customized with your own CSS, making it suitable for dashboards, SaaS products, or internal tools. Events emitted by flowy enable integration with your own data model, so you can sync block positions, connections, and metadata back to a database or application state. It is framework-agnostic, so it can be dropped into vanilla JavaScript projects or wrapped inside React, Vue, or other frameworks.