Tools · SPBoucher
Menu

launchd

In-depth entry

by Apple Inc. · Service · also known as launchctl, LaunchAgents, LaunchDaemons

macOS's built-in service manager that starts, supervises and schedules daemons and per-user agents from property-list job definitions

ProprietaryFreeLocalSelf-hostable
Visit official site Compare

Checked Nov 2, 2026

Overview

launchd is the init and service-management system of macOS, the first process started by the kernel and the component responsible for launching every daemon, agent and scheduled job on the system. Apple documents it in the Daemons and Services Programming Guide (now in the Documentation Archive) and in the launchd and launchd.plist manual pages; the launchctl command loads, unloads, starts and inspects jobs.

A job is described by an XML property list placed in one of a few directories: /Library/LaunchDaemons for system-level daemons that run as root or a configured user regardless of who is logged in, and /Library/LaunchAgents or ~/Library/LaunchAgents for per-user agents that start at login. Keys such as Label, ProgramArguments, RunAtLoad, KeepAlive, StartInterval, StartCalendarInterval, WatchPaths and Sockets define when the job runs and whether launchd should restart it. Because launchd owns the sockets and relaunches crashed processes, programs written for it should not daemonize themselves.

On a Mac used as a server or cluster node, launchd is what keeps long-running services alive across reboots: Homebrew's brew services, PM2's pm2 startup and many monitoring agents simply generate launchd plists. Daemons are the right choice on machines without a graphical login session; agents are needed when a job must interact with the user's session.

Caveats: the plist format is verbose and error-prone, debugging relies on launchctl print and log files rather than a friendly UI, the launchctl syntax changed between the legacy load/unload and the newer bootstrap/bootout domain-based commands, and Apple's conceptual guide has not been updated since 2016.

Editorial note on uncertainty. Apple's conceptual guide is archived (2016). Current behavior of launchctl subcommands is documented only in the manual pages shipped with macOS.

Capabilities

  • Launch at boot (daemons) or at login (agents)
  • Keep-alive supervision and automatic restart
  • Interval and calendar scheduling without cron
  • Path and directory watching triggers
  • Socket activation with on-demand launch
  • Per-job environment, user, working directory and stdout/stderr redirection

Typical workflows

  1. Keep a Node or Python service running on a headless Mac Studio
  2. Run a nightly backup script with StartCalendarInterval
  3. Start a process whenever files land in a watched folder
  4. Replace a user cron job with a LaunchAgent

Strengths

  • Built into every macOS install; nothing to add
  • Survives reboots and crashes without external supervisors
  • Single mechanism for scheduling, supervision and socket activation

Limitations

  • Verbose XML plists and opaque error messages
  • Two generations of launchctl syntax cause confusion
  • Agents need a logged-in session; daemons cannot touch the GUI
  • Official conceptual documentation is archived and dated

Prerequisites

  • macOS
  • Administrator rights for system-level daemons

Who it is for

  • macOS administrators and power users
  • Developers deploying services on Mac servers
  • Anyone replacing cron on a Mac

Alternatives & comparison

PM2 is a user-space process manager for Node (and other) applications with a friendlier CLI, log handling and clustering; on macOS it ultimately registers itself with launchd to survive reboots, so the two are layered rather than exclusive. Docker supervises processes inside containers and restarts them by policy, which isolates dependencies but adds a VM layer on macOS. Ansible can write launchd plists across a fleet but is a configuration tool, not a supervisor. Compared with cron, launchd adds supervision and event triggers and is what Apple maintains going forward.

  • Ansible

    Agentless configuration management and orchestration tool that runs YAML playbooks over SSH, with collections for clouds, network gear and applications

    Open sourceOpen source
  • Docker

    Container platform combining the Docker Engine runtime, the Compose and Build tooling, Docker Desktop for macOS and Windows, and the Docker Hub registry

    MixedOpen source
  • PM2

    Production process manager for Node.js and other long-running programs with cluster mode, log handling, restart policies and boot-time startup scripts

    Open sourceOpen source
Compare launchd with its alternatives →

Sources & verification

Primary sources consulted for this record. Claims are tied to the fields each source supports; the automated link checker re-verifies every URL on a schedule.

  • Official documentation
    Creating Launch Daemons and Agents

    https://developer.apple.com/library/archive/documentation/MacOSX/Conceptual/BPSystemStartup/Chapters/CreatingLaunchdJobs.html

    Supports: capabilities, workflows, limitations

    checked Nov 1, 2026
  • Official documentation
    Script management with launchd in Terminal on Mac

    https://support.apple.com/guide/terminal/script-management-with-launchd-apdc6c1077b-5d5d-4d35-9c19-60f2397b2369/mac

    Supports: capabilities, workflows

    checked Nov 1, 2026
  • Official site
    Daemons and Services Programming Guide – Introduction

    https://developer.apple.com/library/archive/documentation/MacOSX/Conceptual/BPSystemStartup/Chapters/Introduction.html

    Supports: name, summary, description

    Apple Documentation Archive; last updated 2016

    checked Nov 1, 2026
Confidence
High
Reviewed
Nov 1, 2026
Links
Broken · Nov 2, 2026

Spotted an error?

Broken link, outdated license, wrong category, or a tool that no longer exists? Tell us; reports are reviewed by the editor.

Shortcuts

Apple Inc. · macOS automation

Apple's built-in visual automation app for macOS, iOS and iPadOS that chains app actions, scripts and system functions into runnable shortcuts

ProprietaryFreeLocalNov 2, 2026

AppleScript

Apple Inc. · macOS automation

Apple's English-like scripting language that drives scriptable macOS applications through Apple events, run from Script Editor, osascript or other automation tools

ProprietaryFreeLocalMaintenanceNov 2, 2026

Hammerspoon

Hammerspoon contributors · macOS automation

Open-source macOS automation app that exposes system APIs to a Lua configuration file for hotkeys, window management and event-driven scripts

MITOpen sourceFreeLocalNov 2, 2026

Alfred

Running with Crayons Ltd · macOS system utilities

macOS launcher and productivity app whose paid Powerpack adds workflows, clipboard history, snippets and custom searches

ProprietaryFreemiumPaidLocalNov 2, 2026

Karabiner-Elements

pqrs.org (Takayama Fumihiko) · macOS system utilities

Free, public-domain keyboard customizer for macOS that remaps keys and defines complex modifications through JSON rules at the driver level

UnlicenseOpen sourceFreeLocalNov 2, 2026

Keyboard Maestro

Stairways Software Pty Ltd · macOS automation

Commercial macOS macro application that runs sequences of actions from hotkeys, typed strings, application, time, device and system triggers

ProprietaryPaidLocalNov 2, 2026