impulse-labs-sas/brainstack

Shared second brain for humans and AI assistants. Self-hostable. MCP-native.

BrainStack keeps your notes as Markdown in Postgres. It exposes them to any MCP-compatible AI assistant: Claude Code, Claude Desktop and claude.ai, Cursor, Codex, Gemini CLI, Continue, Cline and others. People use the web app, which covers what Obsidian did: a file tree, a Markdown editor with wikilinks, full-text search, a graph, and import of the .md files you already have. Assistants read and write the same notes through the MCP server, and can gather everything a question refers to in a single call; the graph’s Sentinel view replays what they read, and turns a question of your own into a prompt, with the notes it needs, to paste into an assistant or an IDE.

Every account has its own vault, and any folder can be shared with other people, read-only or with write access.

Status: pre-alpha. Built by Impulse Labs.

Why

If you work with several AI assistants, you keep retyping the same context everywhere: design docs in the repo, in Claude Projects, in Cursor rules, in Gemini, in your head. BrainStack is the single source of truth. Your assistants pull what they need through MCP and write back when you tell them to. One brain, every AI.

What’s inside

apps/
  server/     Hono + tRPC + MCP server (Node 24+), with its own OAuth 2.1 provider for MCP clients
  web/        Next.js 15 web app: react-aria-components + CodeMirror 6
packages/
  core/       Markdown parsing, wikilink resolution, Postgres store and full-text search
  skill/      Canonical AI instructions + adapters for every major client

Storage is any Postgres. Sign-in is email and password, with optional Google sign-in and optional TOTP. MCP clients connect through OAuth or with an API key.

Quick start (self-host)

You need Docker. The compose file runs Postgres, the server, the web app and Caddy, which serves them all on one origin with automatic TLS.

git clone https://github.com/Impulse-Labs-SAS/brainstack.git
cd brainstack
cp .env.example .env
# edit .env: at least DOMAIN, PUBLIC_ORIGIN and POSTGRES_PASSWORD
docker compose up -d

Then open your PUBLIC_ORIGIN and create your account right away. The first account on an instance is its owner and needs no email verification. After it, sign-up is closed.

The schema is created on first start and updated by every new version on its own. Already have a Postgres? Set DATABASE_URL in .env and BrainStack uses it instead of the bundled one.

Email: optional for one person, needed to add others