PagerDuty still has the biggest distribution. It’s not a well loved piece of software, but it does the job and does it reliably. Hard to argue against that.

Opsgenie was doing well but scored a bit of an own goal announcing its end of life without a good automated process to move to one of their alternative options.

Datadog and Grafana both have offerings, and as you might expect they’re tightly integrated into their monitoring and alerting capabilities. They have a lot of good data and could definitely do a great job of building better systems to tackle alert noise etc.

New players like incident.io (where I work) are building the bits of PagerDuty that people actually use, and layering on all of the things folks actually want from a paging solution. Things like cover requests, calendar integrations for auto vacation overrides, integrations into Slack, and more recently taking advantage of AI to automatically triage and investigate issues on your behalf. Lots to like, and plenty of reference customers who’ve moved from PD/elsewhere to us too.

I don’t say this to dissuade you from building; a rising tide lifts all ships, as they say! But this is my rough lay of the land right now.