persistent-memory
(3)
Mem0 wants AI to remember you. The trick is knowing what to forget.
A chatbot that forgot its users sent two founders toward a different business: selling memory to the people building AI. Mem0’s wager is that useful context should survive a conversation - and a change of model.
MemVerge
MemVerge is a Milpitas, California AI infrastructure software company that started out virtualizing DRAM and persistent memory into pooled 'Big Memory' and has since pivoted toward the AI era. Its Memory Machine products maximize GPU utilization through memory tiering, pooling and transparent checkpointing, and in 2025 it launched MemMachine, an open-source AI memory layer that gives LLMs and agents persistent episodic, profile and procedural memory across sessions, models and clouds. Founded in 2017 by CEO Charles Fan, CTO Yue Li and chairman Shuki Bruck, the company has raised about $43.5M from investors including Intel Capital, Cisco, NetApp, SK hynix and Lightspeed.
Letta
Letta is a San Francisco AI research lab and platform for building stateful agents - AI that remembers, learns, and improves itself over time. Spun out of UC Berkeley's Sky Computing Lab from the viral MemGPT project, Letta gives developers an open framework, API, and cloud service where agent state (memories, messages, reasoning, tool calls) is persisted in a database rather than lost when it falls out of the context window. The company positions itself as the open alternative for developers who want to build agents that behave less like stateless chatbots and more like continuously learning digital collaborators.