How to write an EF Core 11 value converter that maps a null in the database to a non-null value in code
EF Core never passes null to a value converter by default. Here is the internal convertsNulls constructor that changes that, the IsRequired(false) call it depends on, why it cannot work at all for enums and other value types, the WHERE col = NULL trap it creates, and the two patterns that do the job without an internal API.