12 Factor Apps

Use declarative formats for setup automation, to minimize time and cost for new developers joining the project;

Have a clean contract with the underlying operating system, offering maximum portability between execution environments;

Are suitable for deployment on modern cloud platforms, obviating the need for servers and systems administration;

Minimize divergence between development and production, enabling continuous deployment for maximum agility;

And can scale up without significant changes to tooling, architecture, or development practices.