I have built SqlFlow, which is an open-source durable workflow engine backed by PostgreSQL or SQL Server, with SDKs for .NET, Java, Python, and Go. Workflows support retries, checkpoints, rate limitng, scheduling, and suspension while waiting for events.
It took a large deal of inspiration from Absurd, but it expands on the core concepts.
Instead of polling the database, it supports native database features such as PostgreSQL LISTEN / NOTIFY, SQL Server Service Broke, and you could also use NATS. The durable state always remains in your SQL database.
Each SDK comes with a complete example, that models an AI Agent Workflow:
- https://github.com/bytefish/SqlFlow/tree/main/sdks
I would love to hear your feedback.