Zipkin is an open-source distributed tracing system. It collects timing data from applications so that teams can troubleshoot latency in service architectures. Applications are instrumented with a tracer library and report their data to Zipkin, most commonly over HTTP or Kafka. Users look up a trace by its ID or search by service, operation name, tags and duration, and a dependency diagram shows how requests flow between services. Zipkin is delivered as software that you run yourself, as a Java jar or a Docker image.
Zipkin is licensed under Apache 2.0 and developed in the open by the OpenZipkin organisation on GitHub. It is not a hosted service from a single vendor. Trace data is kept in memory or in a backend you choose, such as Apache Cassandra or Elasticsearch, so it stays wherever you deploy it. For a European organisation, data location, access control and retention are therefore in its own hands. The web interface has no built-in authentication, so the operator needs to secure access.