Home / Founders / Charles Packer
Packer co-created MemGPT as a Berkeley Ph.D. student, an early system for giving AI agents long-term memory, and now runs Letta, which turns that research into open-source tools for agents that learn.
Charles Packer is co-founder and CEO of Letta, a San Francisco, California, company that builds open-source software for AI agents that remember past conversations and work and improve over time.
Joining Berkeley's Sky Computing Lab
He was a Ph.D. student in computer science at UC Berkeley, where he worked in Berkeley AI Research and the Sky Computing Lab, the group behind Spark and Ray, according to his personal site. He and Sarah Wooders met there as Ph.D. students under the same advisors, Joseph Gonzalez and Ion Stoica.
Creating MemGPT
At Berkeley the pair built MemGPT, which treated a language model's limited context like a computer's memory, moving information in and out so an agent could keep track of far more than fits in one prompt. The open-source project drew a large developer following, and he has said that using it made starting a company straightforward, in a Felicis conversation with Stoica.
Spinning Out Letta
He and Wooders started Letta in 2024, with Gonzalez and Stoica as advisors. He has said that the traits that make an agent useful, such as personalization, self-improvement and planning, all come down to managing memory. Letta's tools let developers see and edit what an agent remembers, according to PR Newswire.
