src
 └ adapters                → presentation layer to external world, controllers, serializer (formatter) & routes
   └ controllers           → recieve request from routes, send response back, forward req to usecase
   └ serializers           → format/structurize output for frontend
 └ application             → app specific logic, usecases(orchestrate the flow), security
   └ security              → abstraction/interface for security & Auth
   └ usecase               → controls business flow, take cross entity actions
 └ domain                  → core business rules, entities
   └ entities              → core entities with business rules & constraints, i.e user, order
   └ repositories          → abstractions for database access calls
 └ infrastructure          → external libraries, frameworks, databases & tools implementations