Unit of Work is a transaction boundary for related changes, not a DbContext wrapper. With EF Core you already have it. With Dapper, you coordinate the connection and transaction yourself.

Inconsistent API errors make clients hard to write. Problem Details give ASP.NET Core a standard shape for HTTP failures, from expected endpoint errors to global exception handling.

Database transactions ensure multiple operations succeed or fail together. EF Core wraps SaveChanges in an implicit transaction, with explicit transactions and savepoints for more complex flows.