Nestor Ventosa contributed to the newrelic/entity-definitions repository by both defining new entities and improving data integrity through targeted configuration management. He delivered the NGEP Teams Hierarchy Levels entity type, establishing a scalable model for hierarchical data within the NGEP domain, with manual expiration and non-alertable settings to support governance and future integrations. Using YAML for configuration and entity definition, Nestor also addressed a critical bug by correcting eventName mapping in golden_metrics.yml, ensuring accurate metric-to-entity associations and reducing misattributed metrics in dashboards. His work demonstrated careful attention to release safety and data accuracy without introducing API changes.