Worked on the open-telemetry/opentelemetry-cpp repository to deliver unified multi-observer callback support for metrics, focusing on enhancing observability and performance in C++ environments. Introduced a new API that allows a single callback to observe multiple instruments through the MultiObserverResult, reducing redundant computations and streamlining data collection for high-cardinality metric workloads. This feature consolidated observation logic, improving scalability and simplifying instrument authoring for production deployments. The work centered on API design and metrics, aligning with 2025 performance goals by enabling more efficient metric data pipelines. No major bugs were addressed during this period, as the emphasis remained on feature development.