How to Monitor Cron Jobs in Ruby on Rails

Rails apps schedule work in several ways, and each can fail quietly: a whenever-generated crontab that a deploy forgot to update, a sidekiq-cron schedule that stopped because Sidekiq is down, or a rake task that errors before it logs anything useful.

A rake task on cron

0 3 * * * cd /app && bin/rails backup:run && curl -fsS https://api.cronguard.dev/v1/ping/<your-uuid>

Pinging from Ruby

For start/success/failure signalling inside a job or task:

require "net/http"

BASE = "https://api.cronguard.dev/v1/ping/<your-uuid>".freeze

def ping(suffix = "")
  Net::HTTP.get(URI(BASE + suffix))
rescue StandardError
  nil # never let monitoring break the job
end

ping("/start")
begin
  BackupService.call
  ping
rescue StandardError
  ping("/fail")
  raise
end

sidekiq-cron

Put the ping at the end of the worker’s perform method so it only fires on a clean run, and add a separate monitor that pings every minute to confirm Sidekiq itself is alive.

Get alerted

Point those pings at CronGuard, set the schedule, and you’ll get instant multi-channel alerts whenever a Rails job fails to check in — no agent required. Free to start.