Serialization

This covers JSON, Protocol Buffers, and MessagePack for .NET, with a strong focus on AOT compatibility and moving away from Newtonsoft.Json. The comparison tables are genuinely helpful for deciding between formats: use System.Text.Json with source generators for APIs and web clients, Protobuf for gRPC and service-to-service communication where schema evolution matters, and MessagePack when you need compact binary without managing .proto files. The guidance on avoiding BinaryFormatter and reflection-based serializers is spot on. The examples show real patterns like combining multiple JsonSerializerContext instances and handling polymorphic types with JsonDerivedType. If you're still using Newtonsoft.Json or wondering which binary format fits your use case, this gives you concrete decision criteria and working code.