Arc

Arc is a macOS desktop app for orchestrating coding agents across groups of projects. You organize project folders into named groups, and each group carries its own knowledge sections (notes, docs, playbooks, links, and custom sections) stored as plain files on disk, either inside the app's data folder or in a folder you link. Built with Electron, Svelte, and SQLite. Apple Silicon only.

Pre-release website: https://tests.myedgenet.com

What it does

• Sessions with a brain and workers. Ask a question or request a change across a group; a brain agent plans the work and starts workers, each in its own git worktree on a session branch, then merges their changes.
• Three providers on your own subscriptions. Agents run on the Claude Code, Codex and Cursor command-line tools already installed and signed in on your Mac. Choose a provider and model for the brain and the workers, or let Auto pick; Arc falls back to another provider when one isn't available. No API keys.
• Approvals. Risky actions (pushing, destructive commands, leaving the working copy) wait in Needs attention until you approve them.
• Change review. Review each session's diff file by file, leave notes, and push from Arc.
• Stepping in. Open any worker's terminal, ask it something, and hand it back.
• Commands and skills. Run your Claude Code, Codex and Cursor commands from the "/" list.
• Usage. Token counts per agent, plan usage meters, a Usage page and suggestions for cutting token spend.
• Agent loading. Choose which of your MCP servers, plugins, skills and hooks the brain and the workers load.

Development

Requires Node 22 or newer and pnpm 10.

pnpm install          # installs dependencies and prepares native modules for Electron
pnpm dev              # run the app with hot reload
pnpm test:unit        # Vitest, run under Electron's Node so one better-sqlite3 binary serves everything
pnpm test:e2e         # build, then Playwright-for-Electron
pnpm exec playwright test   # e2e against the existing build
pnpm lint
pnpm typecheck
pnpm format
pnpm package          # build and produce release/Arc-<version>-arm64.dmg and release/mac-arm64/Arc.app

Set HARNESS_USER_DATA=<dir> to keep the database, logs, and knowledge folders out of ~/Library/Application Support/Arc.

Smoke check

After pnpm package, verify the packaged app can open its database and run migrations:

HARNESS_USER_DATA="$(mktemp -d)" release/mac-arm64/Arc.app/Contents/MacOS/Arc --smoke
echo $?   # 0 on success, non-zero on failure

Installing the .dmg

1. Open release/Arc-<version>-arm64.dmg and drag Arc into Applications.

2. Builds are ad hoc signed (no Apple Developer ID, no notarization). If you copied the app from another machine or downloaded it, macOS marks it as quarantined and Gatekeeper will refuse to open it. Clear the flag once:

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

3. Launch Arc. Your data lives in ~/Library/Application Support/Arc and logs in ~/Library/Logs/Arc.

Third-party fonts

Arc bundles Orbitron, Rajdhani and JetBrains Mono (through the @fontsource packages, pinned in package.json). All three are licensed under the SIL Open Font License 1.1. The license text and copyright lines are in resources/licenses/FONTS-OFL.txt, which is also copied into the packaged app under Contents/Resources/licenses/.

App icon

The icon sources are resources/icon/arc-icon.svg (full) and arc-icon-small.svg (16 to 64 px), and the DMG background is resources/dmg/background.svg. After editing them, run pnpm icons (macOS only) to regenerate the committed resources/icon.icns, resources/icon.png and resources/dmg/background.tiff.