A personal second brain for Claude Code — and a shared memory layer for mixed AI + human teams. One command to install. Markdown vault (browsable in Obsidian) + auto-capture hooks + semantic memory (GBrain). Composes with any agent stack: gstack, openclaw, Hermes, or plain Claude Code — they all read and write the same vault.

Everyone gets the same engine, with their own data — everything stays local on their machine.

It all runs inside Claude Code (terminal/IDE). No bot, no server, no shared cloud.

Requirements: macOS, Claude Code, a free ZeroEntropy key (embeddings — free account, no card).

git clone <URL_OF_THIS_REPO> brain-in-a-box
cd brain-in-a-box
./install.sh # asks for the ZE key, installs everything, overwrites nothing

Then the onboarding (15 min, fills in your profile):

cd ~/Documents/Brain && claude
# paste: "Read onboarding/ONBOARDING.md and run it to personalize me."

install.sh also installs Obsidian (if you don't have it) so you can browse your brain visually — open it and "Open folder as vault" → ~/Documents/Brain.

Verify your install any time (safe, runs in a throwaway temp dir — never touches your real brain):

./test-hooks.sh # runs all 5 hooks end-to-end, reports pass/fail

Garry Tan's gstack ships 23 Claude Code skills (a "virtual engineering team": CEO, eng manager, designer, reviewer, QA, CSO, release engineer...). brain-in-a-box installs it alongside on request — they compose: gstack's specialists work, brain-in-a-box captures and remembers.

./install.sh --with-gstack

You get slash commands like /office-hours, /plan-ceo-review, /review, /qa, /retro, /investigate, /cso, /learn (and 15 more). All read your vault for context, all can write decisions/learnings back into it.

The vault treats humans (Team/) and AI agents (Agents/) as first-class entities with the same schema. New teammate, human or AI, gets a file. Any agent can query "who knows X" and get a unified answer.

Decisions live in Decisions/ (one file per decision, with options + trade-offs + status) — answer "why did we choose X?" six months later in one query. Skills live in Skills/ in gstack's SKILL.md format (YAML frontmatter + triggers + workflow) — directly invokable by Claude Code, gstack, or any compatible runtime.

In team mode, all of these federate with the company vault (BrainCo/) — your personal entities stay personal, your shared ones are searched across the org.

Beyond the personal brain, a team can share a company brain (decisions, projects, clients, processes, "who does what") — each member still keeps their personal brain. Architecture: the company brain is a private Git repo, added as a 2nd GBrain source (company) on each member's machine, git-pulled nightly. No server, 100% local per member.

Admin (once):

cd brain-in-a-box && ./setup-company.sh # scaffold + git init
cd ~/Documents/BrainCo
gh repo create <org>/brain-company --private --source=. --push

Each member:

git clone <REPO_URL> brain-in-a-box && cd brain-in-a-box
./install.sh --company https://github.com/<org>/brain-company

They then have their personal brain + the company source (federated → found by gbq query, or targeted via --source company).

Contributing (open contribution):

cd ~/Documents/BrainCo
# edit/add a .md (decision, project note, client sheet)
git add -A && git commit -m "decision X" && git push

Each member's nightly pulls the team's contributions + re-indexes. The dream cycle dedups/consolidates.

• Live your life in Claude Code: the corrections you give are captured in lessons.md, your sessions summarized in Journal/. Zero effort.
• Recall: gbq query "what did we decide about X?" → answer from your memory, with the source.
• Skillify: gbq skillify <url-or-file> extracts a SKILL.md draft from a tweet, article, or doc (via gbrain). Drop it in ~/Documents/Brain/Skills/ and your agents can use it.
• Brainstorm / code search: gbq brainstorm "<question>" (idea generation), gbq code-def <symbol> / code-refs <symbol> (when you indexed a code repo as a source). All gbrain commands are safe through gbq — it routes reads through the lock-safe path and writes via clean wait.
• In the morning: the dream cycle deduped/consolidated overnight.

• Everything is local: your vault, your index, your key. Nothing goes to a third party (except the text embedding sent to ZeroEntropy at indexing time — see their policy).
• Never a secret in the vault (the file-protection hook + the directives remind you).
• Found a security issue? See SECURITY.md — please use GitHub Security Advisories, not public Issues.

PRs welcome. Read CONTRIBUTING.md for the workflow (the master branch is protected — every change goes through a PR). MIT licensed (see LICENSE). Changelog tracked in CHANGELOG.md.

cd brain-in-a-box && git pull && ./install.sh # idempotent, re-applies without breaking

• No Telegram bot — separate add-on.
• Embeddings = ZeroEntropy (free, no-card account). For a 100%-local/offline variant (nothing leaves the machine), an Ollama nomic-embed-text variant is planned — not for cost (ZE is already free), just for full privacy.