Cron monitoring without a dedicated tool: PagerDuty, Opsgenie, Sentry Crons compared

The cron monitoring question I hear most isn't Healthchecks vs Cronitor. It's whether the PagerDuty, Opsgenie, or Sentry subscription already sitting in the stack covers it. The honest answer differs by tool, and none of the three do what the pricing page implies.

I'm the developer behind illari, one of the four options below. I've tried to say plainly what each of the other three actually ships versus what you'd have to build yourself, and where they're genuinely the right call.

The options

Pricing and plan gating move around; check each vendor's current page before deciding.

PagerDuty

PagerDuty pages the right person once an event arrives. It has no native concept of a job that should have run and didn't. Its own heartbeat monitoring guide is a build-it-yourself workflow: cache variables to track the last check-in, an orchestration rule to notice the gap, a webhook to reset it. That's a real project, not a checkbox.

Pick it if: you need actual on-call, rotations, and phone or SMS paging. Point a dedicated monitor's alerts at it as a channel rather than trying to build detection inside it. See illari vs PagerDuty.

Opsgenie

Opsgenie Heartbeats are a genuine check-in monitor: expect a ping every fixed interval, alert when it's missing. Gated to Standard and Enterprise plans, so it's not something a free-tier account can reach for. The bigger fact most evaluators miss: Atlassian stopped selling Opsgenie in June 2025 and is retiring it by April 5, 2027, folding on-call into Jira Service Management.

Pick it if: Heartbeats are already included in a Standard seat you're not dropping. There's no reason to add a second tool before you have to, but plan the eventual migration rather than waiting for the forced one. See illari vs Opsgenie.

Sentry Crons

Sentry Crons is a real check-in monitor, but it's a feature inside an error-tracking product, and the pricing follows that shape. The first monitor is free; every one after that is metered individually. Alerts beyond email, Slack, PagerDuty, the rest, are gated behind the Team plan.

Pick it if: the team already lives in Sentry for errors and performance, and one or two monitors on email alerts is genuinely enough. See illari vs Sentry Crons.

illari

Where I've tried to make this different from reusing a platform you already pay for:

• The detection ships, not a recipe for building it. One HTTP request at the end of a job is the whole integration. No orchestration rules, no cache variables.
• Flat $20, no seat minimum, no per-monitor meter. PagerDuty requires five paid seats before you can page anyone. Sentry meters monitors individually. illari is the same $20 whether that's 5 jobs or 300.
• Every alert channel on every plan. Slack, Discord, Telegram, PagerDuty, incident.io, ntfy, Pushover, and webhooks, none of them behind a higher tier.
• Checks what the run reported, not just whether a ping arrived: exit code, a run far off its own duration baseline, and threshold rules on numbers the job sends (rows < 1, cost_usd > 5).

illari isn't trying to replace PagerDuty's paging or Sentry's error tracking. It hands both of them something to act on, which is the part none of the three do natively.

Pick it if: you want the detection working today, at a flat $20 with no seat minimum and no per-monitor meter, without adopting an incident platform or an APM product to get it.

The short version

None of the three actually notice a missed job on their own, cheaply. PagerDuty needs the detection built and five paid seats before it can page anyone. Opsgenie has it, but only above a Standard seat, on a product with a 2027 end date. Sentry has it too, metered per monitor, with Slack and PagerDuty alerts locked behind the Team plan. That gap is the actual case for a dedicated monitor.

illari is $20 flat, 25 monitors free, every alert channel included, and one HTTP request from the job, whether or not you're already paying for one of the three above. The comparison against dedicated heartbeat monitors (Healthchecks, Cronitor, Dead Man's Snitch) covers the rest of that decision. Read the docs.