Checkly

Checkly was built for engineering teams that needed synthetic monitoring tight enough to catch problems before real users did, with checks that could run complex multi-step browser interactions rather than simple HTTP pings. Founded in 2018, the product allows developers to write monitoring checks using Playwright — the same test automation framework many teams already use for end-to-end testing — and run them on a continuous schedule from Checkly's globally distributed check runner network. The monitoring-as-code philosophy, reinforced by the Checkly CLI, allows check configurations to live in version control alongside application code and be deployed through CI/CD pipelines.

Checkly runs browser checks and API checks from a network of check runner locations spread across AWS regions globally. Results stream back to the Checkly dashboard in near real time, with alert conditions evaluated against configurable thresholds and failures routed through integrations with PagerDuty, Opsgenie, Slack, email, and webhooks. The Checkly CLI allows teams to pull monitoring configuration into their repositories using a TypeScript- or JavaScript-based configuration format, run checks locally during development, and deploy check configuration through GitHub Actions or other CI pipelines. This code-first approach has positioned Checkly well with developer-focused organisations that prefer infrastructure-as-code patterns.

Checkly service disruptions are particularly consequential because the failure of a monitoring tool is invisible in a specific way: checks stop running but do not alert on their absence by default, meaning a Checkly outage may leave teams with no indication that their monitoring is dark. Check runner failures in specific geographic regions cause false positives — a website that is actually healthy appears to be failing from the affected location — or false negatives when global check aggregation logic suppresses alerts assuming the check location is at fault. Alert webhook delivery failures prevent Checkly failure notifications from reaching PagerDuty or Slack, breaking the paging pipeline. The Checkly dashboard and API may become unavailable during backend infrastructure issues, blocking check management and result retrieval.

Outage.gg tracks Checkly service status using real-time community reports from developers and operations teams. If checks are not running, alerts are not delivering, or the Checkly dashboard is unavailable, the live status page shows current impact from the Checkly user community.