Built My Own Prometheus Service Discovery for Oracle Cloud Because a 3-Year-Old PR Never Got Merged

There is a specific kind of frustration reserved for when you know a problem is solved, you can see the solution, and you still cannot use it. That is how this project started. The Context: Setting Up Observability From Scratch I was building out observability from scratch across Oracle Cloud Infrastructure - multiple tenancies, multiple regions, a decent number of compute instances spread across compartments. The goal was full coverage: every VM enrolled in monitoring, no gaps, no guesswork. When you are starting from zero, one of the first things you ask is how Prometheus is going to discover what it needs to scrape. For AWS you have EC2 service discovery built right in. Same for GCP, Azure, Hetzner, DigitalOcean. You configure credentials, set some filters, and Prometheus takes care of the rest. OCI is not on that list. I searched. I found a pull request in the Prometheus repository opened by an engineer at Oracle. It was exactly what I needed. It was also three years old and had ne