# Monitoring & Observability > Selected Engineer ApS work demonstrating Monitoring & Observability — the achievements that prove it. - [Automated delivery of 20 GIS data pipelines and app data ETL processes, streamlining infrastructure automation and reporting.](https://software.engineer.company/portfolio/automated-delivery-of-20-gis-data-pipelines-and-17/) - [Built first‑party error monitoring and OpenTelemetry tracing rather than buying them — payload sanitising, spike and regression detection, symbolication and a synthetic heartbeat — behind 11 operator views.](https://software.engineer.company/portfolio/built-first-party-error-monitoring-and-tracing-98/) - [Stopped an application filling memory at 41 MB a second — a recorded 111 GB of compressed pages on a 36 GB machine — by bounding every event stream, subscribing by event type and putting a rate budget on logging, taking 610,996 log lines down to 1,411.](https://software.engineer.company/portfolio/stopped-an-application-filling-memory-at-41mb-a-second-155/)