LangChain AI Updates: October 13, 2026

1. LangGraph.js 1.5.0 Makes Parallel Write Ordering Deterministic and Matches Python

LangChain. LangGraph.js 1.5.0 and @langchain/langgraph-checkpoint 1.2.0 now apply and replay parallel writes to the same DeltaChannel in (task_path, task_id, idx) order, replacing task-id order, which shuffled parallel writers from run to run because task IDs are hashes that include the checkpoint ID. The change aligns JavaScript behavior with Python LangGraph, and every saver (memory, SQLite, Postgres, Redis, MongoDB) now stores a task path: SQLite and Postgres gain a task_path column migrated automatically on setup(), while rows written before the upgrade keep their old order. Custom checkpoint savers need updating, since putWrites accepts an optional taskPath and getTuple/list must return pending writes in the new writesSortKey order. Source