Checkpoints

Checkpoints persist graph state for fault tolerance and inspection.

BaseCheckpointSaver Trait

Implement BaseCheckpointSaver to store and load checkpoints. The engine calls it after each superstep.

MemorySaver

For tests and prototyping, use MemorySaver—an in-memory implementation that does not persist across process restarts.

Auto-save Behavior

The engine automatically saves after each superstep. No extra configuration is required once a saver is provided.

Benefits

• Fault tolerance: Restart from the last checkpoint after crashes.
• State inspection: Load checkpoints to debug or analyze graph state.
• Resume: Combine with interrupt/resume for human-in-the-loop workflows.