Checkly

Judgement

What it is

Developer tool

What it does

Synthetic monitoring using Playwright browser scripts and API checks, defined as code and run on a schedule from many locations.

Adopt it when

Developers want end-to-end tests of critical user flows running as production monitoring from the same code.

Watch out

Browser check runs are billed by volume, so frequent checks get costly.

Ready for

Production-ready

Runs as

Cloud service and command line

Built with

TypeScript and Playwright

What the license allows

Closed source: you use it under the maker's terms and cannot change or resell the code.

Judged on 2026-11-03 from the maker's description and Wikipedia. The license and age lines are worked out directly.

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Under it

Every program, Checkly included, runs on a microchip.

How compilers were built, back to punched paper tape