whenly

Lightweight persistent job scheduler for Python — SQLite-backed, minimal dependencies.

from whenly import Scheduler

s = Scheduler()

@s.every(5, "minutes")
def sync_data():
    ...

@s.cron("0 9 * * MON")
def weekly_report():
    ...

s.start()  # background thread

Features

• SQLite persistence — jobs survive restarts
• Cron expressions via croniter
• Interval scheduling — every N seconds/minutes/hours
• One-off delayed jobs — run once after a delay
• Decorator or programmatic API
• Thread-safe background runner
• CLI for basic management
• Zero external dependencies (except croniter for cron support)

Install

pip install whenly

Quick Start

from whenly import Scheduler

s = Scheduler()

# Interval jobs
@s.every(30, "seconds")
def poll_api():
    print("Polling...")

# Cron jobs
@s.cron("0 */2 * * *")
def cleanup():
    print("Running cleanup...")

# One-off delayed job
@s.later(10, "minutes")
def send_notification():
    print("Hello!")

# Or pass a function directly
s.later(30, "seconds", func=poll_api)

# Start the scheduler (non-blocking)
s.start()

# Or run blocking
# s.run()

Programmatic API

s.add(poll_api, every="60s")
s.add(cleanup, cron="0 3 * * *")
s.disable("poll")
s.enable("poll")
s.run_now("poll_api")
print(s.jobs)

CLI

whenly list
whenly run

License

MIT

Part of the thecliffhanger open source suite.