Checkly

Profile

Checkly is a developer-first synthetic monitoring and observability platform that unifies API monitoring, browser testing, and uptime verification through a code-based workflow powered by Monitoring as Code principles. Built on Microsoft's Playwright automation framework and supporting TypeScript/JavaScript configuration, the platform enables engineering teams to define monitoring infrastructure as version-controlled code that lives alongside application code. Checkly serves organizations from individual developers through large enterprises, processing tens of millions of checks daily across a global infrastructure spanning more than twenty data center locations. The platform integrates OpenTelemetry distributed tracing with synthetic monitoring results, providing correlation between check failures and backend infrastructure issues for rapid root-cause analysis.

Focus

Checkly addresses the fundamental challenge of detecting and resolving production issues in distributed systems where traditional monitoring approaches create operational friction. Legacy tools separate testing from monitoring, forcing teams to maintain duplicate test suites and configure monitoring through manual UI workflows rather than code. The platform eliminates this duplication by allowing teams to write Playwright-based browser tests and API checks once, then deploy them as both development tests and production monitors. By implementing configuration as code, teams apply the same version control, review processes, and automation to monitoring that they use for application development. This approach particularly benefits platform engineers, SREs, and DevOps teams managing microservices architectures where comprehensive monitoring of API flows and user journeys proves essential for maintaining reliability.

Background

Checkly was founded by Hannes Lenke, who previously founded TestObject and served as General Manager EMEA at Sauce Labs, bringing extensive experience in testing and monitoring technology. The company secured venture capital backing from prominent firms including Accel, CRV, and Balderton Capital, with angel investors including executives from Vercel, Microsoft, and GitHub. The platform has achieved production adoption across organizations including Vercel, commercetools, 1Password, Autodesk, and LinkedIn, with documented implementations demonstrating measurable improvements in incident detection and support ticket reduction. The Checkly CLI operates under the Apache 2.0 open source license, while the core platform remains a proprietary managed service. Active development continues with regular releases and feature additions, supported by the founding team's ongoing leadership.

Main features

Monitoring as code with TypeScript configuration

Checkly enables all monitoring configuration to be defined in TypeScript or JavaScript files stored in version-controlled repositories alongside application code. Teams create a root-level configuration file defining global defaults, then organize individual checks in designated folders using descriptive naming patterns. The Checkly CLI processes these files using glob patterns, discovers all checks, validates configuration through IDE features like autocompletion and type checking, and deploys them to Checkly's infrastructure. This workflow integrates seamlessly with CI/CD pipelines, allowing checks to be tested locally during development, deployed automatically on commits to specific branches, and triggered as part of deployment processes, ensuring monitoring configuration receives the same rigorous review and change tracking as application code.

Playwright-powered browser checks with comprehensive debugging

Browser checks leverage Microsoft's Playwright framework to automate real browser interactions simulating end-user behavior across complex workflows including login processes, form submissions, and multi-step transactions. Developers write Playwright tests using JavaScript or TypeScript, utilizing Playwright's code generation feature to record user interactions and automatically generate test code. When checks execute in production across globally distributed infrastructure, they run against real browsers in controlled environments with consistent properties. Failed checks provide comprehensive debugging artifacts including full video recordings, Playwright trace files capturing DOM snapshots, network waterfall data, console logs, and complete browser state at each step, enabling rapid root-cause analysis without requiring manual reproduction of failures in development environments.

OpenTelemetry integration for distributed trace correlation

Checkly automatically instruments HTTP requests made by synthetic checks with OpenTelemetry trace context headers, enabling correlation between check failures and backend distributed traces. When instrumented requests hit backend services, the trace context flows through the entire request path, automatically correlating all backend spans with the originating synthetic check. Rather than requiring separate observability infrastructure, Checkly directly ingests traces related to failed checks by filtering on vendor-specific markers, dramatically reducing data volume and associated costs compared to collecting all traces. When checks fail, alert notifications include direct links to trace visualizations showing complete request flows including backend spans, network waterfall data, and browser screenshots, providing engineers with immediate context for root-cause identification without navigating between multiple dashboards.