Install MUON on macOS

• Node.js 20.10 or newer and npm on your PATH for the installer. Node 24 is recommended.
• macOS on Apple silicon (arm64). Intel and universal builds are not available.
• git installed and on your PATH. MUON works on git workspaces and shells out for identity, diffs and merges.
• At least one coding-agent CLI installed and logged in. MUON drives your own agents; it never ships or authenticates one for you.

Download the app from the download page: grab MUON-<version>-arm64.dmg, open it, and drag MUON into Applications. Every artifact ships with a published SHA-256 checksum (SHA256SUMS) so you can verify what you got before you open it.

Because the app carries no Developer ID signature, macOS blocks the very first launch and calls MUON an app from an “unidentified developer.” You only do this once.

1. 01

   System Settings → Privacy & Security → Open Anyway

   Double-click MUON.app once. When macOS blocks it, open System Settings → Privacy & Security, scroll to the “MUON was blocked” notice, and click Open Anyway. This is the path on current macOS releases.

2. 02

   Older macOS: right-click → Open

   On older releases you can instead Control-click (or right-click) MUON.app, choose Open, then confirm Open in the dialog.

3. 03

   Or: clear the quarantine flag from the Terminal

   xattr -dr com.apple.quarantine /Applications/MUON.app

   This is the standard macOS mechanism for an unsigned app you trust — the same thing “Open Anyway” does. Run it once, after the app is in /Applications.

Node.js 20.10 or newer and npm on your PATH are required; Node 24 is recommended. Download the installer first:

curl -fsSLO https://getmuon.com/install.sh

Use Node to verify the installer on macOS. The system LibreSSL does not support this signature check. Save the following as verify.mjs. Cross-check the embedded key and fingerprint with the release signing keys bulletin.

import { createHash, createPublicKey, verify } from "node:crypto";
import { writeFileSync } from "node:fs";
// MUON release-manifest key. Cross-check the keyId at https://docs.getmuon.com/release-keys
const KEY = "MCowBQYDK2VwAyEAj38Q783SKDGtQhxTS24pOX2UMgsPipkL1RzlnJHpFxY=";
const KEY_ID = "e63d771f74c661945d3674cf633b8b07d7628536ba9783a958e13b91f341cbb6";
const get = async (url) => { const r = await fetch(url); if (!r.ok) throw new Error(`${url}: HTTP ${r.status}`); return Buffer.from(await r.arrayBuffer()); };
const der = Buffer.from(KEY, "base64");
if (createHash("sha256").update(der).digest("hex") !== KEY_ID) throw new Error("key fingerprint mismatch");
const channel = JSON.parse(await get("https://download.getmuon.com/channels/stable.signed.json"));
const { version } = JSON.parse(Buffer.from(channel.payload, "base64"));
if (!/^\d+\.\d+\.\d+$/.test(version)) throw new Error("unexpected version");
const installer = await get("https://getmuon.com/install.sh");
const signature = await get(`https://download.getmuon.com/releases/${version}/install.sh.sig`);
const key = createPublicKey({ key: der, format: "der", type: "spki" });
if (!verify(null, installer, key, signature)) { console.error("SIGNATURE INVALID. Do not run install.sh."); process.exit(1); }
writeFileSync("install.sh", installer);
console.log(`install.sh verified for MUON ${version}`);

node verify.mjs

Only if it prints “install.sh verified”, run:

bash install.sh

That installs muon (the CLI — it auto-starts the local brain on first use, so there is no server to run) and muon-tui (the full-screen terminal cockpit) and muon-mcp (the MCP server). On macOS it also installs the desktop app, which carries the brain; pass --no-desktop for the CLI alone, --desktop-only for only the app, or --replace-desktop to replace an existing app.--desktop explicitly selects the macOS default. Then run:

Run muon login and finish sign-in in your browser. A locked distributed install refuses work with exit code 12; sign in and retry.

muon setup

The setup wizard connects your agents. Check readiness with muon setup --check, then run muon doctor for diagnostics. Prefer help from your agent? Set up with your agent.

The npm package @getmuon/cli is not published yet. Use the verified installer.

It verifies your GitHub identity (MUON stays locked until you do), registers MUON as an MCP server with the coding agents you choose, and starts the brain and runner. For the details, see the CLI reference and the MCP guide.

Before running install.sh, verify its detached signature with the published manifest key. The release signing keys page lists both public keys, their fingerprints, and the exact verification commands.

MUON is not signed with an Apple Developer ID certificate and is not notarized. Treat it as a controlled build, not (yet) a certificate-verified one.

• Why: Developer ID signing requires an active Apple Developer Program membership; the entitlements, notarization hook and config seam already exist so it can flip on later with no rework.
• What it means for you: macOS quarantines and warns on first launch. There is no other behavioral difference — MUON still runs entirely on your machine.
• How to trust the build: every release ships a published SHA256SUMS file next to the download — verify the DMG's checksum before opening it.

muon update --check          # report available updates
muon update --dry-run        # show what would run
muon update --cli-only       # CLI, TUI and MCP only
muon update --desktop-only   # desktop only

muon update --host <url> selects a release host.

From a terminal, muon updateupdates the CLI and the app together and brings MUON back up if it was running. In the app, the sidebar's Updates panel checks MUON's release feed when you click Check for updates, or on every launch if you turn that on (it is off by default).

An app installed in /Applications applies the update itself. It downloads the update, verifies it against the feed, swaps the app in place and relaunches, keeping a rollback copy until the new version boots. Every step is your click. A copy anywhere else can only tell you a newer release exists.

Uninstalling: delete MUON.app. Clearing the data directory is a manual step today.