# OpenTelemetry Demo 3.0 introduces breaking schema changes and new signals > OpenTelemetry Demo 3.0 renames custom attributes, restructures Compose deployment, and adds agentic, profiling, OpAMP, load-generation, and test capabilities. Canonical URL: https://www.devobs.io/news/news-opentelemetry-demo-30-release/ By: Amara Okafor Published: 2026-09-06T11:58:54.649Z Updated: 2026-09-06T11:58:54.649Z Event date: 2026-07-28 Section: Developer tools OpenTelemetry released Demo 3.0 on July 28 with deliberate compatibility breaks and a wider set of observability examples. In the [release article](https://opentelemetry.io/blog/2026/we-broke-the-demo/), “we broke” refers to changes that require users to update integrations, including an attribute namespace migration and a new Compose layout. ## Existing queries need explicit migration The demo's custom telemetry attributes moved from the app.* namespace to demo.*. Dashboards, alerts, and saved queries that filter on the old names will stop matching until they are updated. That makes an upgrade test straightforward: inventory every query containing app., migrate it, and compare results against a known request before removing the old environment. The project also replaced docker-compose.yaml with a split compose.yaml structure. The new modes can omit Kafka or the bundled observability stack. Automation that assumes the old filename or service set therefore needs review. Run the same startup command used in continuous integration and verify every expected service and health check rather than relying on an interactive launch. ## The teaching surface is broader Version 3.0 adds an agentic demo built with a LangGraph ReAct agent, an MCP server, and a chatbot interface, with telemetry across the flow. It also adds continuous profiling and an OpAMP server, while improving load generation and the test suite. Those additions let teams examine more signal types and control-plane behavior in one bounded application. They do not establish that the release contains intentionally faulty game-day scenarios. A useful exercise is to trace one generated request across the new components, verify the renamed attributes, and confirm profiles and other signals retain consistent resource identity. Demo 3.0 is best treated as updated learning infrastructure with documented migration work. The breaking changes themselves are the upgrade lesson: telemetry schemas and deployment files are contracts, even in a sample environment. ## Source references -