NuGet.Client/docs/aot-compatibility.md

AOT and Trimming Compatibility

NuGet has IsAotCompatible enabled for all NuGet.Core libraries and the code itself is AOT compatible. However, NuGet still utilizes Newtonsoft.Json for deserialization, which uses reflection and is not AOT/trim compatible.

We are in the process of migrating to System.Text.Json source-generated deserialization. Until the migration is complete, both deserialization paths coexist, gated under a feature switch. Enabling the feature switch ensures NuGet.Protocol uses System.Text.Json instead of Newtonsoft.Json, allowing the linker to trim the Newtonsoft.Json code path entirely.

Using NuGet in a Native AOT Application

If you consume NuGet libraries in a native AOT app, add the following feature switch to your project file:

<ItemGroup>
  <RuntimeHostConfigurationOption Include="NuGet.UseSystemTextJsonDeserialization"
                                  Value="true"
                                  Trim="true" />
</ItemGroup>

This tells NuGet to use the AOT-safe System.Text.Json path and tells the linker the value is constant so it can eliminate the Newtonsoft.Json code path from the binary.