So pour one out for the DLL that refused to die. And then maybe add a reference to it, because your appsettings.json file still needs parsing. Have a Newtonsoft war story? A custom converter that saved your bacon? Share it in the comments below.
public class UnixDateTimeConverter : JsonConverter<DateTime> newtonsoft json dll
Install-Package Newtonsoft.Json The DLL itself will land in your project's packages folder or be referenced via the .NET runtime's shared framework (if using the Microsoft.NET.Sdk ). Newtonsoft.Json is the COBOL of JSON serialization—not because it's old and crusty, but because it’s everywhere , it works , and rewriting what it powers would be a colossal waste of time. Its API is the mental model for JSON in .NET that an entire generation of developers grew up on. So pour one out for the DLL that refused to die
NullValueHandling = NullValueHandling.Ignore, ContractResolver = new DefaultContractResolver NamingStrategy = new SnakeCaseNamingStrategy() , Formatting = Formatting.Indented ; string json = JsonConvert.SerializeObject(myObject, settings); Need to serialize a DateTime as a Unix timestamp? Map an enum to a string instead of an int? Handle a polymorphic type hierarchy where the base class doesn’t know its children? JsonConverter is your answer. A custom converter that saved your bacon
Even with Microsoft's own System.Text.Json now baked into the platform, Newtonsoft.Json remains deeply embedded in countless production systems, legacy projects, and even modern greenfield development. Why? Because it’s battle-hardened, absurdly flexible, and packed with features that feel like magic.
Microsoft’s System.Text.Json is the future for high-performance, modern cloud-native apps. But Newtonsoft.Json is the reliable, duct-tape-and-ingenuity library that still holds vast swaths of the .NET ecosystem together. It didn't just solve JSON serialization—it defined it.