However I have never used it for work because most of the stuff I work on is old but highly valuable code.
It is quite simple though:
1. Decide on an architecture that scales well.
2. Redesign the architecture to maximise opportunities for auto generating code/schemas/protocols/client/server/DB etc.
3. Define your actual application in a declarative language. I use my own custom language but you can use JSON/YAML/…
4. Write a generator that reads the declarative files and generates as much of the code needed as possible to implement the application.
5. Hand code what remains (basically the core biz logic).
That’s pretty much it. I have done this exercise more than 9 times and I learned a lot doing it. I highly recommend giving it a go yourself. You learn a true super power and it is great fun.
https://github.com/mintyPT/sal (still need to finish v2)
How long have you been going this? You create a custom language instead of using json or yaml?