Flowise https://flowiseai.com/ does something similar as well! I would check them out for sure if you're looking more on the OSS side.
We had the core node logic open source at one point, but closed it because we weren't seeing many contributions and it was less overhead once we started implementing things like node versioning, integrations, credentials, etc.
We still do deploy on-prem for enterprises that need it secure on their own cloud, and will link into open-sourcing a self-hosted version in the futur efor sure!
