C# Records and Immutability Refactoring

A record gives the compiler value-based equality, generated hashing, a useful ToString method, and nondestructive copying with the with expression. A positional record class also creates init-only properties, so values cannot normally be changed after construction. [Microsoft Learn](https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/builtin-types/record)

No. Record immutability is shallow: an init-only property cannot point to a different array after construction, but the contents of that array can still change. Use immutable collections or defensive copies when nested data must also stay unchanged. [Microsoft Learn](https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/builtin-types/record)

Records were introduced with C# 9 and the .NET 5 era. They are intended mainly for data-centric types such as value objects, messages, and DTOs rather than every class in an application. [Microsoft .NET Blog](https://devblogs.microsoft.com/dotnet/welcome-to-csharp-9-0/)

Usually not. Microsoft notes that records are a poor fit for Entity Framework Core entities because EF Core relies on reference equality and tracks object identity. [Microsoft Learn](https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/builtin-types/record)