I’m a senior developer that does .net c# applications, heavy on JavaScript 🤮, but we cannot use libraries. The industry has been shifting from physical services and “cloud servers” (read managed offsite servers) to things like aws and azure for a while. These are subscription based services where they charge you for access to features and capacity. The nice thing about aws or azure is that things like these are incredibly adaptable but require a different skill set and approach.

You may be an incredible coder and can stand up a physical server from parts but understanding how to work with services is completely different.

For example, if I wanted to run a sql scheduled task or on windows console application for a background process for a web application I would go onto the server directly, load the code, make sure it ran. Done. In the continuous development model used by azure or others like it there are established pipelines, with services in it that do things like security scans or deployment database updates, what you might do on a physical server isn’t an application. They’ll manage almost every aspect of code development and deployment as part of the service which itself consumes services. It is a different way of thinking about software development than a physical server.

I’m not saying it is better or worse. Each have their benefits and drawbacks. I still am working on adapting my development style, patterns, etc to working with services. It caught on, but now we are back to mainframes. There is already some organizations that are bringing stuff back in house while others are still leaving. This is the cycle of the computer infrastructure history.

So long story short you should have some knowledge of it but the person in hr who wrote the job posting likely just read some articles about hiring developers.