Configuration management is such a fun problem to solve! You can use libraries like dynaconf (Python) or viper (Go) and they’re super fancy and will probably provide everything you want (and a bit more).
Today I wanted to code, though. For a pet project, I wanted something as simple as: well, try to get this configuration from env vars, and try to look in a secret manager for those you can’t find. I wanted no dependencies for this small task, for this small project, and for those starting with configuration management, it might be a fun way to understand the power those libraries can give you.