Checkly

Checkly is a monitoring platform that uses code-based synthetic monitoring to continuously check that your APIs and critical user flows actually work in production — catching problems before your users do. Rather than just checking whether a server responds, Checkly runs real, scripted checks (including full browser-based end-to-end tests) against your application from around the world, verifying that key journeys — logging in, checking out, calling an API — behave correctly. This proactive, behavior-based monitoring gives teams confidence that their most important flows are working, not just that their servers are up.

The platform lets developers write checks as code, using familiar tools and frameworks, to monitor API endpoints and simulate real user interactions in a browser, running these checks on a schedule from multiple locations. When something breaks — an API returns errors, a checkout flow fails, performance degrades — Checkly alerts the team quickly, with the details needed to diagnose the issue. By embracing a "monitoring as code" approach that fits modern development workflows, and by testing real user-facing functionality, Checkly bridges the gap between testing and production monitoring in a way developers appreciate.

Checkly is used by development and DevOps teams that want to ensure their APIs and key user flows are reliable in production and prefer a code-based, developer-friendly approach to monitoring. By catching failures in critical journeys early — from anywhere in the world — it helps teams maintain reliability, protect the user experience, and resolve issues before they cause significant impact. Its synthetic, end-to-end focus complements traditional observability by verifying that things actually work as users would experience them. As applications grow more complex and reliability becomes ever more important, proactive synthetic monitoring of real flows is increasingly valuable. For development teams that want to monitor their APIs and critical user journeys in production with code-based synthetic checks, Checkly offers a powerful, modern and developer-friendly solution.