crnd

Pronounced "crowned"

Cron daemon built for agents. No interactive prompts. Structured output. Real OS processes. Runs entirely local.

AI coding agents (Claude Code, Cursor, Codex) can't use crontab — it requires interactive editing and produces unstructured output. crnd gives them a cron daemon they can actually drive.

Why crnd

Most cron tools are built for humans clicking around. crnd is built for scripts and agents that need to:

• Schedule jobs without interactive prompts
• Parse structured output (crnd list --json)
• Stream logs from running processes
• Kill/stop jobs by name
• Trust that jobs run as real OS processes (not some container abstraction)

Everything runs locally. No cloud, no Docker, no account, no network calls.

crnd vs the alternatives

| | crnd | crontab | launchd | systemd timers | |---|---|---|---|---| | Agent-friendly (no interactive UI) | Yes | No (requires EDITOR) | No (XML plist) | Partially | | Structured JSON output | Yes (--json) | No | No | journalctl --output=json | | One-time scheduled tasks | Yes (-i 5m, -a ISO) | No | Yes | Yes | | Per-job timezone | Yes | No | No | Yes | | Cross-platform | macOS, Linux, Windows | Linux/macOS | macOS only | Linux only | | Run history & logs | Built-in | No | Console.app | journalctl | | Job management (pause/resume/stop) | Yes | No | launchctl | systemctl | | Zero config install | npx crnd | Pre-installed | Pre-installed | Pre-installed | | Skill system for AI agents | Yes | No | No | No |

Platform support

| Platform | Architecture | Status | |---|---|---| | macOS | Apple Silicon (arm64) | Supported | | macOS | Intel (x64) | Supported | | Linux | x64 | Supported | | Linux | arm64 | Supported | | Linux | x64 musl | Supported | | Linux | arm64 musl | Supported | | Windows | x64 | Supported |

Install

# global install
bun i -g crnd
npm i -g crnd

# or run directly
bunx crnd
npx crnd

# or homebrew
brew install ysm-dev/crnd/crnd

Agent Skill

Install the crnd skill for your coding agent (Claude Code, Cursor, Codex, etc.):

npx skills add ysm-dev/crnd

This teaches your agent how to schedule and manage cron jobs using crnd.

30 seconds to your first job

# start daemon (happens automatically, but let's be explicit)
crnd daemon start

# schedule a backup at 2am UTC daily
crnd schedule -n backup -s "0 2 * * *" -- rsync -a ~/docs ~/backup

# schedule a one-time job in 5 minutes
crnd schedule -n reminder -i 5m -- say "Time to stretch!"

# run it now
crnd run-once -n backup

# check status
crnd status -n backup

That's it. Job definitions live in ~/.config/crnd/jobs.toml — edit it directly and the daemon picks up changes.

Commands

crnd schedule -n NAME -s "CRON" -- command args   # create/update job
crnd schedule -n NAME -a "ISO_TIMESTAMP" -- cmd   # one-time job (absolute)
crnd schedule -n NAME -i "5m" -- cmd              # one-time job (relative)
crnd list                                         # all jobs
crnd status -n NAME                               # job details
crnd runs -n NAME                                 # run history
crnd logs -n NAME -s                              # stream stdout/stderr
crnd run-once -n NAME                             # trigger now
crnd pause -n NAME                                # pause scheduling
crnd resume -n NAME                               # resume
crnd stop -n NAME                                 # graceful stop (SIGTERM)
crnd kill -n NAME                                 # hard kill (SIGKILL)
crnd delete -n NAME -f                            # remove job
crnd export                                       # dump jobs.toml
crnd import -f jobs.toml                          # load jobs
crnd daemon install                               # autostart on login
crnd doctor                                       # check setup
crnd upgrade                                      # update to latest version
crnd upgrade --check                              # check for updates

All commands default to text output; use --json for machine-readable output.

jobs.toml

[jobs.backup]
command = ["rsync", "-a", "/src", "/dst"]
schedule = "0 2 * * *"
timezone = "UTC"
timeout_ms = 600000

[jobs.deploy]
command = ["./deploy.sh"]
run_at = "2026-02-01T10:00:00Z"

Edit this file directly. The daemon watches it and syncs automatically.

Paths:

• macOS: ~/Library/Application Support/crnd/
• Linux: ~/.config/crnd/
• Windows: %APPDATA%\crnd\

How it works

• Each job spawns a real OS process via Bun.spawn
• State lives in SQLite, job definitions in TOML
• Daemon runs per-user, binds to 127.0.0.1
• Autostart via launchd (macOS), systemd user (Linux), or Task Scheduler (Windows)
• Stdout/stderr saved per-run in state/runs/<jobId>/<runId>.out|.err
• Auto-updates like Homebrew (checks every 24hrs, updates before commands)

Auto-Update

crnd checks for updates automatically (like Homebrew). To disable:

export CRND_NO_AUTO_UPDATE=1

Or configure the check interval (default 24 hours):

export CRND_AUTO_UPDATE_SECS=3600  # check every hour

Manual update:

crnd upgrade              # update now
crnd upgrade --check      # just check, don't update

Built with

• Bun — runtime, bundler, test runner, single-binary compiler
• TypeScript — type-safe codebase
• Hono — daemon HTTP/RPC server
• Drizzle + SQLite — state & run history
• Croner — timezone-aware cron parsing
• Zod — input validation
• Biome — lint & format

Development

bun install
bun run dev          # start daemon in dev mode
bun run build        # compile single binary
bun test

License

MIT