Kubernetes API uses JSON. JSON is JavaScript Object Notation. So naturally the best approach to work with JSON is to write JavaScript or TypeScript code. You can just output JSON and consume it with kubectl. You can read data from whatever format you want, process it and output JSON. You can write your little functions to reduce boilerplate. There are many options that are obvious once you just embrace JavaScript.

Of course most other programming languages will work just as well, it's just JavaScript being the most natural fit for JSON.