krun

Minimal process manager for Linux — a lightweight PM2 alternative using systemd user services.

3MB static binary. Zero dependencies. No daemon.

Install

CGO_ENABLED=0 go build -ldflags="-s -w" -o krun .
sudo cp krun /usr/local/bin/

Commands

Process Management

# Start an app
krun start api --cmd "node dist/main.js" --cwd /srv/api

# Start with options
krun start worker --cmd "python worker.py" \
  --cwd /srv/worker \
  --env NODE_ENV=production \
  --env PORT=3000 \
  --max-memory 512M \
  --instances 3 \
  --log-file /var/log/worker.log \
  --error-file /var/log/worker.err \
  --log-dir /srv/worker/logs \
  --interpreter python3 \
  --cron-restart daily \
  --no-autorestart

# Start from ecosystem config
krun start ecosystem.json

# Stop / restart / reload
krun stop api
krun restart api
krun reload api          # graceful reload (SIGHUP then restart)

# Stop/restart all
krun stop all
krun restart all

# Remove app (stop + delete service)
krun remove api
krun remove all

Monitoring

# List all apps (with PID, CPU, memory, uptime, restarts)
krun list

# Detailed info
krun info api

# Real-time dashboard (refreshes every 2s)
krun monit

# Show environment variables
krun env api

# Show app config as JSON
krun config api

Daily Log Rotation

# Start with daily log rotation (logs saved by date)
krun start api --cmd "node server.js" --log-dir /srv/api/logs

# Creates files like:
#   /srv/api/logs/api-2026-03-13.log
#   /srv/api/logs/api-2026-03-13-error.log
#
# New log file is created each day automatically.
# --log-dir overrides --log-file/--error-file when both are set.

Logs

# Follow logs (like tail -f)
krun logs api

# Show last 100 lines without following
krun logs api --lines 100 --nostream

# Flush logs
krun flush api
krun flush all

Save & Restore

# Save current running apps config
krun save

# Restore saved apps after reboot
krun resurrect

Startup

# Enable auto-start on boot (loginctl enable-linger)
krun startup

# Disable auto-start
krun unstartup

Misc

krun reset api           # Reset restart counter
krun version
krun help

Ecosystem Config

Create ecosystem.json:

{
  "apps": [
    {
      "name": "api",
      "cmd": "node dist/main.js",
      "cwd": "/srv/api",
      "env": {
        "NODE_ENV": "production",
        "PORT": "3000"
      },
      "max_memory": "512M",
      "instances": 1
    },
    {
      "name": "worker",
      "cmd": "python worker.py",
      "cwd": "/srv/worker",
      "interpreter": "python3",
      "auto_restart": true,
      "log_dir": "/srv/worker/logs"
    }
  ]
}

Then: krun start ecosystem.json

Command Aliases

Command	Aliases
list	ls, status
info	describe, show
logs	log
monit	monitor, dash
remove	delete

How It Works

• Generates systemd user service files at ~/.config/systemd/user/krun-<name>.service
• Restart=always with 3s delay for crash recovery
• loginctl enable-linger for boot persistence
• Logs via journalctl or daily file rotation with --log-dir
• App configs saved at ~/.config/krun/apps.json
• Memory limits via systemd MemoryMax
• Cron restart via systemd timers

Requirements

• Linux with systemd (Debian, Ubuntu, Arch, etc.)
• systemctl, journalctl, loginctl