install

Install Cairn v0.11.0

Linux and macOS

Run the shell installer to add cairn, cairn-mcp, and cairn-embedd to your path. It installs uv if needed and uses Python 3.11 or later.

curl -fsSL https://cairncli.com/install.sh | sh

macOS with Homebrew

brew tap moonbase2090/tap
brew install cairn

Release archives

Download an archive for Linux x86_64, macOS Apple silicon or Intel, or Windows x64 from the Cairn v0.11.0 release. Each archive includes Python. Check the archive against SHA256SUMS before you install it.

./install.sh
powershell -File .\install.ps1

One project

The machine install does not create a vault. In the project directory, run:

export CAIRN_AGENT=claude-myproj
cairn init --yes
cairn bootstrap

Set CAIRN_AGENT to an ID for your agent and project. bootstrap writes .mcp.json, a section of AGENTS.md, and four onboarding memories.