BTrees

BTrees is a Python package that provides a set of scalable, persistent object containers built around a modified BTree data structure. It is heavily optimized for use within ZODB's "optimistic concurrency" paradigm, offering efficient storage and retrieval of large mappings by only loading relevant nodes into memory. The current version is 6.3, released on November 16, 2025, with an active release cadence, often aligning with Python version support.