Open Observability Summit + OTel Community Day 2025

Migrating from proprietary tracing systems to OpenTelemetry can be challenging, especially when applications rely on custom span and resource attributes that do not align with semantic conventions. Organizations need a strategy to unify legacy telemetry with OpenTelemetry standards without disrupting existing queries, visualizations, or alerts.

This session presents a real-world case study from Comcast, highlighting how the OpenTelemetry Weaver tool was used to create a unified schema combining semantic conventions with existing attributes. This approach allows teams to gradually adopt standard attributes while maintaining compatibility with current setups, ensuring continuity and reducing migration friction.

The session details how Weaver was configured using Jinja templates to generate outputs in multiple formats—JSON, YAML, and Markdown—supporting backend ingestion and schema documentation. This enabled consistency across pipelines and improved clarity for engineering teams reviewing trace attribute definitions. The talk also highlights how flexible namespacing integrated domain-specific attributes alongside standardized ones without sacrificing backend compatibility.