iTerm2

iTerm2 is a terminal emulator for Mac OS X that does amazing things.

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Repository: gnachman/iTerm2


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CLAUDE.md

Code Best Practices

- Avoid writing javascript, html, or CSS that's more than one line long in Swift. Create a new file and use the existing template mechanism to load it.
- After creating a new file, git add it immediately
- To add a file to the Xcode project, use tools/add_file_to_xcodeproj.rb <file_path> <target_name> (e.g., tools/add_file_to_xcodeproj.rb sources/Example.swift iTerm2SharedARC)
- In Swift, use it_fatalError and it_assert instead of fatalError and assert, which do not create useful crash logs. In ObjC, assert is ok although ITAssertWithMessage is preferable. Asserts are enabled in release builds.
- Don't write more than one line of inline javascript, html, or css. Instead create a new file and load it using iTermBrowserTemplateLoader.swift
- Don't create dependency cycles. Use delegates or closures instead.
- To run unit tests in ModernTests, use tools/run_tests.expect. It takes an argument naming the test or tests, such as tools/run_tests.expect ModernTests/iTermScriptFunctionCallTest/testSignature
- When renaming a file tracked by git (and almost all of them are) use git mv instead of mv
- To make a debug build run tools/build.sh (or tools/build.sh Development). This saves logs to tmp/build.log and shows only errors/warnings on failure.
- Little scripts or text files that are used for manual testing of features go in tests/
- The deployment target for iTerm2 is macOS 12. You don't need to perform availability checks for older versions.
- Don't replace curly quotes with straight quotes. Same for apostrophes and single quotes. If you need help typing a curly quote, just ask. Here are some you can copy and paste: ‘’“”
- In user-visible strings do not use " except as a shorthand for inch. Prefer curly quotes like “ and ”. I know this goes against your nature, but fight hard here.
- Never use auto layout in the terminal window. This includes the toolbelt. It virally spreads and breaks autoresizing. It is fine to use it in other windows without a lot of existing autoresizing mask-based code (e.g., the AI chat window)
- The deployment target is macOS 12. Don't add availability checks for 12 and lower.
- Never git add submodules without express written permission.
- Don't include AI-generated markdown files (summaries, plans, etc.) in commits — only ship code.
- Avoid duplicate expressions; hoist shared computations into a named const before branching.
- Don't change defaults silently.
- Use [iTermUserDefaults userDefaults] instead of [NSUserDefaults standardUserDefaults]
- Use make run to build and run a debug build.
- Do not use associated objects (objc_getAssociatedObject or objc_setAssociatedObject) without express written permission.
- You should treat warnings as errors.
- If you get stuck, ask for help. It's better to ask me to look at something in the debugger than to flail around for a long time.
- If your changes introduce compiler warnings, fix them.


README.md

<div align="center">

iTerm2

macOS Terminal Replacement

!Version
!Platform

Website • Downloads • Documentation • Features

</div>

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About

iTerm2 is a powerful terminal emulator for macOS that brings the terminal into the modern age with features you never knew you always wanted.

Key Features

- tmux Integration - Native iTerm2 windows/tabs replace tmux's text-based interface. Run tmux -CC and tmux windows become real macOS windows. Sessions persist through crashes, SSH disconnects, and even app upgrades. Collaborate by having two people attach to the same session.
- Shell Integration - Deep shell awareness that tracks commands, directories, hostnames, and usernames. Enables click-to-download files via SCP, drag-and-drop uploads, command history per host, recent directories by "frecency," and marks at each prompt.
- AI Chat - Built-in LLM chat window that can optionally interact with terminal contents. Link sessions to get context-aware help, run commands on your behalf, or explain output with annotations.
- Inline Images - Display images (including animated GIFs) directly in the terminal. Use imgcat to view photos, charts, or visual output without leaving your workflow.
- Automatic Profile Switching - Terminal appearance changes automatically based on hostname, username, directory, or running command. SSH to production? Background turns red. Different environments get different visual contexts.
- Dedicated Hotkey Windows - System-wide hotkey summons a terminal that slides down from the top of the screen (or any edge), even over fullscreen apps. Pin it or let it auto-hide.
- Session Restoration - Sessions run in long-lived server processes. If iTerm2 crashes or upgrades, your shells keep running. When iTerm2 restarts, it reconnects to your sessions exactly where you left off.
- Built-in Web Browser - Browser profiles integrate web browsing into iTerm2's window/tab/pane hierarchy. Copy mode, triggers, AI chat, and other terminal features work in browser sessions.
- Configurable Status Bar - Per-session status bar showing git branch, CPU/memory graphs, current directory, hostname, custom interpolated strings, or Python API components.
- Triggers - Regex patterns that fire actions when matched: highlight text, run commands, send notifications, open password manager, set marks, or invoke Python scripts.
- Smart Selection - Quad-click selects semantic objects (URLs, file paths, email addresses, quoted strings). Right-click for context actions. Cmd-click to open.
- Copy Mode - Vim-like keyboard selection. Navigate and select text without touching the mouse. Works with marks to jump between command prompts.
- Instant Replay - Scrub backward through terminal history to see exactly what was on screen at any moment, with timestamps. Perfect for catching fleeting errors.
- Python Scripting API - Full automation and customization via Python. Create custom status bar components, triggers, menu items, or entirely new features.
- Open Quickly - Cmd-Shift-O opens a search across all sessions by tab title, command, hostname, directory, or badge. Navigate large session collections instantly.

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Installation

Download

Get the latest version from iterm2.com/downloads

For the bleeding edge without building, try the nightly build.

Build from Source

Note: Development builds may be less stable than official releases.

#### Prerequisites

- No manual prerequisites. make setup will install Homebrew, Xcode,
Rust, and all other dependencies, prompting for confirmation before each privileged step.

#### Clone

bash
git clone https://github.com/gnachman/iTerm2.git

#### Setup (first time)

bash
make setup

make setup is interactive and will prompt for confirmation before any privileged or
security-sensitive operation. It performs the following steps:

- Homebrew -- Installs Homebrew via its official install script
if not already present. Prompts before running the installer (which requires sudo).
- Xcode -- If no Xcode is selected via xcode-select, installs
xcodes (via Homebrew) and
aria2 (for faster downloads), then either selects an
existing /Applications/Xcode*.app or downloads the latest Xcode automatically.
Prompts before running sudo xcode-select and before accepting the Xcode license.
- Rust -- Installs rustup via the official curl | sh
installer if not already present. Prompts before executing the script.
- Homebrew packages -- Installs cmake, pkg-config, automake, perl, and python3 if
missing. If brew link python@3 would overwrite existing symlinks, prompts for
confirmation before proceeding.
- SF Symbols -- Installs the SF Symbols cask (a .pkg installer that requires
sudo). Prompts before attempting the install; continues without it if declined.
- Python/Rust packages -- Installs pyobjc (via pip) and cbindgen (via cargo) if not
already present.
- Submodules and toolchains -- Initializes git submodules, adds the x86_64 Rust
target, and downloads the Metal toolchain.

To skip all confirmation prompts, use make dangerous-setup instead.

After setup, compile native dependencies and build:

bash
make paranoid-deps   # compile OpenSSL, libsixel, libgit2, Sparkle, etc. (sandboxed)
make                 # build iTerm2

Re-run make paranoid-deps whenever your active Xcode version changes -- the file last-xcode-version tracks which version was last used.

If your Xcode version differs from the one committed in last-xcode-version (e.g. you're on an older machine), suppress the noise without committing your local version:

bash
git update-index --skip-worktree last-xcode-version

To undo: git update-index --no-skip-worktree last-xcode-version

#### Build

bash
make Development

#### Run

bash
make run

#### Architecture

Builds target your native architecture by default. To produce a universal (arm64 + x86_64) binary:

bash
UNIVERSAL=1 make Development

#### Code signing

Code signing is disabled by default to keep contributor builds simple. To enable it with the project's signing identity:

bash
SIGNED=1 make Development

#### Building in Xcode

If you prefer building from Xcode instead of the command line:

1. Complete the Clone and Setup steps above.
2. Configure code signing with your team ID:

bash
tools/set_team_id.sh YOUR_TEAM_ID

This script updates DEVELOPMENT_TEAM in all Xcode project files (iTerm2 and its dependencies like Sparkle, SwiftyMarkdown, etc.) so code signing works with your identity.

To find your team ID: Open Keychain Access, find your "Apple Development" or "Developer ID" certificate, and look for the 10-character string in parentheses (e.g., "H7V7XYVQ7D").

No Developer account? Skip this step and select "Sign to Run Locally" in Xcode's Signing & Capabilities tab.

3. Open iTerm2.xcodeproj in Xcode.
4. Edit Scheme (Cmd-<) and set Build Configuration to Development.
5. Press Cmd-R to build and run.

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Development

Contributing

We welcome contributions! Please read our contribution guide before submitting pull requests.

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Bug Reports & Issues

- File bugs: iterm2.com/bugs
- Issue tracker: GitLab Issues

Note: We use GitLab for issues because it provides better support for attachments.

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Resources

| Resource | Link |
| ---------------- | ----------------------------------------------------------------- |
| Official Website | iterm2.com |
| Documentation | iterm2.com/documentation |
| Community | iTerm2 Discussions |
| Downloads | iterm2.com/downloads |

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License

iTerm2 is distributed under the GPLv3 license.

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Support

If you love iTerm2, consider:

- Starring this repository
- Spreading the word
- Sponsoring development

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<div align="center">

Made by George Nachman and contributors

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