Coding Style vs EF Core & Dapper: Pick a Side

A deep dive into the trade-offs between mutable and immutable domain models in C#, specifically how each interacts with EF Core and Dapper. Using a money transfer approval workflow as a concrete example, the content demonstrates that immutable designs (with closed hierarchies, union types, and functional-style fluent APIs) are simpler to use but incompatible with EF Core, which requires mutable entities with flat nullable fields. Mutable designs enable EF Core persistence but introduce accidental complexity through boolean flags, nullable properties, and interface segregation. The conclusion is that the choice of ORM must align with the domain model style — mixing immutable design with EF Core creates costly friction.