Overview

the-brain — an open memory platform for AI with 3-layer cognitive architecture

the-brain is an extensible background daemon that observes your interactions with AI tools and builds a persistent memory tailored to you.

Why the-brain?

AI forgets everything between sessions. the-brain remembers — your patterns, preferences, corrections, and evolving style. It runs locally, costs nothing, and requires zero effort.

Quick Start

curl -fsSL https://the-brain.dev/install.sh | bash
the-brain init
the-brain daemon start

That's it. The daemon watches your AI tools and builds your brain in the background.

→ Full Tutorial — end-to-end walkthrough with a real project

Architecture at a Glance

What the-brain Learns

Corrections: "No, actually use useCallback here" → remembers for next time
Preferences: "I prefer arrow functions" → injected into every prompt
Patterns: Repeated choices → auto-suggests related concepts
Projects: Per-project memory isolation with cross-project promotion
Identity: Your stable self-vector, maintained across retrains

Sections

Start Here — Installation, quickstart, configuration
Core Concepts — Architecture, hook system, memory layers
Customization — Plugins, harvesters, training, storage
Reference — CLI, config schema, MCP tools, env vars
Integrations — MCP server, remote mode, AI tools, team mode, menu bar
Development — Contributing, project structure, testing

Tech Stack

Component	Technology
Runtime	Bun + TypeScript
Database	bun:sqlite + Drizzle ORM
Plugins	hookable event system
Training	Apple MLX (Python sidecar)
Docs	Next.js + Fumadocs