langgraph-checkpoint-grafomem

Signed checkpoints and provable thread erasure for LangGraph.

A drop-in LangGraph checkpointer that wraps the saver you already use and adds two things standard checkpointers can't give you:

• Signed checkpoints — every persisted checkpoint is Ed25519-signed and tamper-evident.
• Verifiable erasure — delete_thread() produces a signed state-transition receipt: cryptographic proof that a user's thread was erased, bound to a key and a timestamp. The receipt for right-to-be-forgotten you can hand an auditor.

Install

pip install langgraph-checkpoint-grafomem

Quickstart

import sqlite3
from langgraph.checkpoint.sqlite import SqliteSaver
from grafomem_checkpoint import GrafomemSerializer, GrafomemCheckpointSaver

# your own signing identity — self-hosted keys, no cloud
conn = sqlite3.connect("memory.db", check_same_thread=False)
inner = SqliteSaver(conn, serde=GrafomemSerializer(private_key, key_id=key_id, trusted_keys=trusted_keys))
saver = GrafomemCheckpointSaver(inner)

graph = builder.compile(checkpointer=saver)   # persist as usual

# right to be forgotten, with proof:
saver.delete_thread("user-123")
receipt = saver.last_receipt("user-123")
assert receipt.verify(public_key)              # signed proof the erasure transition occurred
print(receipt.to_json())

The receipt cryptographically binds the hash of the entire thread's checkpoint history before deletion to the empty state after it — so it commits to the specific data that was erased, not a placeholder.

What the receipt proves (and what it doesn't)

A signed state-transition receipt attests that the erasure operation occurred — the thread's state was overwritten and the transition is bound to a key and a timestamp. It is not a claim of media sanitization or information-theoretic unrecoverability. That precision is the point: an honest, independently verifiable record of deletion, not an unprovable guarantee.

Full example

A runnable reference agent (persist memory, /recall, /forget → verified receipt) lives at grafomem-langgraph-example.

Licensing

This adapter is Apache-2.0. It depends on the GRAFOMEM runtime, which is Fair Source (FSL-1.1-Apache-2.0) — self-host and modify freely; not "open source." See grafomem.com.

A project of Ulissy s.r.l. · the standard is stewarded by the GNS Foundation.