Tracetest is a tool designed to test distributed systems by using the traces they generate, allowing developers to run tests on traces from microservices, Kubernetes applications, and other components before deploying code to production. It enables users to write assertions that validate these traces, ensuring system behavior is correct across service boundaries. Tracetest integrates closely with OpenTelemetry and can either ingest traces directly or query APIs like Highlight's for trace data. By embedding trace-based testing into the development lifecycle, Tracetest promotes a "virtuous cycle" that enhances both testing and observability, motivating developers to ensure accurate telemetry that reflects system behavior. This approach is particularly beneficial for teams adopting OpenTelemetry or focusing on distributed tracing, providing a robust method for leveraging telemetry to prevent regressions and validate systems prior to production deployment.