Sandcastle

Describe what you want. Go home. Sandcastle ships it. 6 AI providers, EU data residency, smart failover, cost intelligence, 20 step types, 236 templates. European-built, open source. pip install sandcastle-ai. Maintained by gizmax on GitHub, where it has earned 83 stars from the community.

It's actively developed around ai-agents, dag, fastapi, and is a solid reference for anyone building with these tools.