Jun

A native macOS workspace for running terminal coding agents (Claude Code, Codex, Pi) side by side, across projects.

• Platform: Apple Silicon Mac, macOS 13 or later
• Built with: Go and MyGo; terminals rendered on the GPU by Ghostty; no WebView
• AI: none of its own. Jun runs the agent CLIs you already have, and makes no AI API calls.
• Status: 0.1.0, the first release. Ad-hoc signed, with no automatic updates.

Install

Download

1. Download jun-0.1.0-arm64.dmg from Releases.
2. Open the DMG and drag Jun into Applications.
3. Open Jun the first time. It is ad-hoc signed, not notarized, so macOS asks first:
   • macOS 13–14: Control-click Jun in Applications → Open → Open.
   • macOS 15 and later: open Jun once and close the warning. Then go to System Settings → Privacy & Security, click Open Anyway next to Jun, and confirm.
   • Or, in a terminal: xattr -dr com.apple.quarantine /Applications/Jun.app

Build from source

An app you build yourself opens without the warning.

• Requires: Go, Git, the Xcode command line tools, and access to proxy.golang.org and GitHub.
  • Go downloads the version that go.mod asks for (1.27.3) on the first build.

git clone https://github.com/bencode/jun.git
cd jun
go tool mygo build -platform darwin/arm64

• Then drag build/darwin-arm64/Jun.app into Applications.

Optional: jun command

alias jun=/Applications/Jun.app/Contents/MacOS/Jun

• Add it to your shell's profile. Then jun . opens the current directory as a project.

Quick start

1. Open a project: ⌘O, or drag a directory onto the project rail at the window's left.
2. Open a terminal: ⌘T.
3. Run an agent in it: claude, codex or pi.
4. Watch your agents: show Global with the rightmost switch at the top right. The Agents view lists every agent in every project, the ones waiting for you first.
5. Look back: Sessions in the side bar (⌘B) lists past sessions. ⌘⇧D reviews a branch's changes.

Features

• Projects and perspectives: many projects in one window. Each has named layouts, such as Work and Review. → Workspace
• Layout: one to three columns, a bottom region, the side bar and Global. Drag tabs between them. → Workspace
• Terminals: Ghostty on the GPU. Shells keep running when their tab is closed or hidden, and can be reopened. → Terminals
• Agents: Claude Code, Codex and Pi across all projects, as waiting, working or idle, with live cards of their screens. → Agents
• Files: the repository by branch and worktree, read-only, with Markdown and image previews. ⌘P searches it. → Files
• Sessions: the project's Claude Code and Codex history. Read a session, or resume it in a terminal. → Sessions
• Diff: a branch's changes, side by side or unified, to review an agent's work before its pull request. → Diff
• Command palette: ⌘K for commands, projects, perspectives and directories.
• Keyboard: shortcuts for tabs, regions, perspectives and projects. They are listed under Keyboard Shortcuts in ⌘K. → Shortcuts
• Themes: Jun's own, or any Ghostty theme, including your own in ~/.config/ghostty/themes.
• Languages: English and Simplified Chinese.
• Settings: one YAML file, opened in Jun with ⌘,. → Settings

Agents	Files
Sessions	Diff

Configuration

File	Holds	Default location	Override
settings.yaml	language, theme, text size, Claude Code folders	~/.config/jun/settings.yaml	JUN_SETTINGS_PATH
config.json	projects, perspectives, layout, tabs	~/Library/Application Support/Jun/config.json	JUN_CONFIG_PATH

• Sessions reads Claude Code's sessions from claude.configDirs in the settings file, else from CLAUDE_CONFIG_DIR, else from ~/.claude. It reads Codex's from CODEX_HOME, else from ~/.codex.
• More: Configuration, Settings.

Limitations

• Apple Silicon Macs only.
• Ad-hoc signed and not notarized, so the first open needs the steps above. No automatic updates.
• Quitting Jun ends its shells. The next start opens fresh shells in the same tabs, without their earlier processes or output. The window's size and position are not saved.
• Agent status is read from each terminal's title and screen. A new version of an agent may show something Jun misses.
• Files and Diff are read-only.

Development

• Requires: macOS 13 or later, the Xcode command line tools, Go 1.27.3 or later.
• Give development builds their own files, so they do not share a layout or settings with the installed app:

JUN_CONFIG_PATH="$PWD/priv/config.dev.json" JUN_SETTINGS_PATH="$PWD/priv/settings.dev.yaml" go run ./cmd/jun
go test ./...
go vet ./...
go tool mygo build -platform darwin/arm64   # build/darwin-arm64/Jun.app and the DMG

Package	Does
cmd/jun	the application's entry point
internal/app	the native UI: regions, views, palette, menus, saving
internal/layout	the model of projects, perspectives, regions and tabs, and its validation
internal/config	the layout file: versions, migrations, atomic writes
internal/settings	the settings file
internal/terminal	terminal sessions and their lifecycle
internal/agent	recognizing agents and reading their status
internal/history	reading Claude Code, Codex and Pi sessions
internal/repo	Git: branches, worktrees, files and diffs
internal/theme	Jun's colors, and Ghostty's themes

• priv/ holds local plans, notes and builds. It is ignored by Git, as are .mygo/ and build/.
• The MyGo dependency and its fork: docs/mygo.md.

Docs

Page	Covers
Workspace	projects, perspectives, regions, tabs and focus
Terminals	shells, background sessions, quitting and restarting
Agents	recognition, status, cards and list, actions
Files	the tree, previews, ⌘P search
Sessions	which sessions, the list, reading and resuming
Diff	opening a diff, what it compares, reading it
Configuration	the layout file: what it saves, how, and what happens on errors
Settings	the settings file and its keys
Shortcuts	every keyboard shortcut
MyGo	the MyGo dependency and its fork