Open source & self-hosting
The Use Brian core is open source under AGPLv3: the brain, the agent, workflows, channels, and the doc surface. Run it on your own machine with one model key, or let usebrian.ai run it for you.
Two ways to run it
Sign in and go. Managed database, channels, connectors, credit billing, and a 30-day Pro trial on every new workspace.
Clone the repo and run it locally. Your data stays on your machine; the only outbound call is to the Gemini API with your own key.
Three commands
Prerequisites: Node 22+, pnpm 10+, and a free Gemini API key.
git clone https://github.com/use-brian/use-brian.git
cd use-brian
pnpm install
pnpm dev # api + doc canvas + web app, opens your browserThe store defaults to an embedded PGLite database under ~/.usebrian/, so there is nothing to install or run besides Node. Point DATABASE_URL at your own Postgres if you prefer a container.
Zero external services, one model key. The brain, the store, and the doc canvas all run on your machine. Optional connectors (Gmail, Calendar, Notion, web search) switch on only when you add their keys.
Tools are governed by what they do, fail-closed: reads run freely, writes ask first, and destructive actions stay blocked until you enable them per tool.
What's open vs what's hosted
- Agent engine, brain, memory, knowledge
- Channels, workflows, doc surface
- MCP server and public API
- Managed database, upgrades, backups
- Plans, credits, team billing
- Monitoring, abuse protection, support
License
AGPLv3, OSI-approved open source with one simple rule: if you run a modified version as a service, publish your changes. A commercial license is available for orgs that can't accept AGPL; contributors sign a CLA.