How do I encapsulate domain logic and preserve state in DDD+Clean Architecture

(For context I am developing in Angular) Historically my applications have tended towards the layered architecture that the Angular fraemwork leads you into. However I feel that the next application I write will benefit from leaning into Clean Architecture and DDD. I have read extensively on the patterns and am preparing for my first real-world excursion into this architecture. However I am stuck on what seems a very simple detail. Domain For simplictity the domain I am working with has an entity called Account. The Account has a method called setVIP which updates a number of properties within the account. My initial intention was to model this as a Class with public methods and private data UI I have a single view that displays the account and allows a number of actions against it e.g. 'set VIP'. There is a Save button which persists any changes made to the API via a single update call Application Will contain a facade to retrieve and update the Account Repository The concrete implementation of my service class called by my facades I will use interfaces to invert dependencies as per Clean Architecture. My problems is very simple. If I use an object of type Account as the request/response between Application and UI, the UI will be able to directly call the setVIP method on the Account object (which likely returns a new Account object for immutibility). My view will contain an Account object and my view populated directly from it. However passing domain objects around is not recommended. Alternatively I can call a facade method to setVIP which in turn would call setVIP on the class. However, it would either have to instantiate a new Account object at the start of the method or retrieve one from some state somewhere. After this it would likely return a DTO to the UI rather than the Domain Object Option 2 would cause me to maintain state in my application layer and then translate it to and from a DTO, just to avoid using the domain object directly. What's the correct approach? Apologies for such a noob question, but we've all got to start somewhere. Thanks

Jun 4, 2025 - 15:10

(For context I am developing in Angular)

Historically my applications have tended towards the layered architecture that the Angular fraemwork leads you into.

However I feel that the next application I write will benefit from leaning into Clean Architecture and DDD.

I have read extensively on the patterns and am preparing for my first real-world excursion into this architecture. However I am stuck on what seems a very simple detail.

Domain

For simplictity the domain I am working with has an entity called Account. The Account has a method called setVIP which updates a number of properties within the account. My initial intention was to model this as a Class with public methods and private data

UI

I have a single view that displays the account and allows a number of actions against it e.g. 'set VIP'. There is a Save button which persists any changes made to the API via a single update call

Application

Will contain a facade to retrieve and update the Account

Repository

The concrete implementation of my service class called by my facades

I will use interfaces to invert dependencies as per Clean Architecture.

My problems is very simple.

If I use an object of type Account as the request/response between Application and UI, the UI will be able to directly call the setVIP method on the Account object (which likely returns a new Account object for immutibility). My view will contain an Account object and my view populated directly from it. However passing domain objects around is not recommended.
Alternatively I can call a facade method to setVIP which in turn would call setVIP on the class. However, it would either have to instantiate a new Account object at the start of the method or retrieve one from some state somewhere. After this it would likely return a DTO to the UI rather than the Domain Object

Option 2 would cause me to maintain state in my application layer and then translate it to and from a DTO, just to avoid using the domain object directly. What's the correct approach?

Apologies for such a noob question, but we've all got to start somewhere.

Thanks