FreeCONF is a an open source project around a single library. You won’t see DevOps in the same way. You can read all about the history of FreeCONF and more about what it is or you can just dig into the examples and get started knocking down walls!
Google, Apple, AWS, Facebook, Cisco, Nokia, Terraform, InfluxDB, Prometheus and Ansible all use this approach to replace configuration files, manual documentation, log scrapers, and custom REST APIs while securing their management operations.