Citadel

An open-source operating layer for Claude Code and OpenAI Codex.

Citadel routes requests, preserves repository state between sessions, coordinates parallel work, applies repository safeguards, and records evidence and handoffs around the coding agent you already use.

Install · Start using it · Trust boundary · Documentation

Install

Requires: Claude Code or OpenAI Codex, Node.js 22+, and a git repository.

Citadel is installed through the plugin marketplace already built into your coding agent. The commands below pin the complete v1.4.3 release; if that tag is not present on GitHub Releases, do not substitute floating main.

Verified release · Project-local activation · Removable · No npm package

OpenAI Codex

Run these commands from the repository you want Citadel to manage:

codex plugin marketplace add SethGammon/Citadel --ref v1.4.3
codex plugin add citadel@citadel-local

Start a new Codex task, review Citadel through /hooks, then give it a real request such as /do review README.md.

Claude Code

Run these commands from the repository you want Citadel to manage:

claude plugin marketplace add SethGammon/Citadel@v1.4.3 --scope local
claude plugin install citadel@citadel-local --scope local

Run /reload-plugins if Claude Code is already open, then give Citadel a real request such as /do review README.md.

Prefer to have your agent install it?

Paste this into Claude Code or Codex. It explains both what Citadel is and the boundary the installer must preserve:

Citadel is an open-source operating layer for Claude Code and OpenAI Codex. It
adds one /do entry point, repository-local state that survives sessions,
guarded multi-step workflows, and reviewable evidence with explicit Needs You
and Resume boundaries.

Install Citadel v1.4.3 from https://github.com/SethGammon/Citadel using this
runtime's native plugin marketplace, then enable it for this repository. Use
project-local defaults and preserve removal evidence for every change. Do not clone main or change shared
configuration, sandbox settings, permissions, or user-wide settings without
asking me.

Only interrupt me for a platform-required trust or reload action, or for a real
configuration conflict. Verify the result, then tell me the single next action.

The platform owns plugin acquisition and executable-code trust. Citadel owns bounded project state and recovery. Plans, digests, receipts, and doctor checks remain available as evidence, but are not user chores on the normal path.

Manual, offline, and high-assurance installation

1. Open the GitHub Releases page and choose an explicit vX.Y.Z release.
2. Download citadel-vX.Y.Z.tar.gz, its .manifest.json, and its .sha256 sidecar into one directory.
3. Compare the archive's SHA-256 with both published values before extraction. A missing asset or mismatch is a blocked install.
4. Extract the archive, then use its single citadel-X.Y.Z/ directory as the immutable source for the governed adoption plan.

From the target repository, with CITADEL_ROOT pointing at that extracted directory, the compact Linux/macOS form is below. Windows users should use the quoted $env:CITADEL_ROOT PowerShell path in Installation.