Updated documentation

docs/usage/options.md

@@ -78,27 +78,26 @@ To limit the maximum depth of nested includes, use `MaximumIncludeDepth`. This i
 options.MaximumIncludeDepth = 1;
 ```
 
-## Custom Serializer Settings
+## Customize Serializer options
 
-We use [Newtonsoft.Json](https://www.newtonsoft.com/json) for all serialization needs.
-If you want to change the default serializer settings, you can:
+We use [System.Text.Json](https://www.nuget.org/packages/System.Text.Json) for all serialization needs.
+If you want to change the default serializer options, you can:
 
 ```c#
-options.SerializerSettings.ReferenceLoopHandling = ReferenceLoopHandling.Ignore;
-options.SerializerSettings.Converters.Add(new StringEnumConverter());
-options.SerializerSettings.Formatting = Formatting.Indented;
+options.SerializerOptions.WriteIndented = true;
+options.SerializerOptions.ReferenceHandler = ReferenceHandler.Preserve;
+options.SerializerOptions.Converters.Add(new JsonStringEnumConverter());
 ```
 
 The default naming convention (as used in the routes and resource/attribute/relationship names) is also determined here, and can be changed (default is camel-case):
 
 ```c#
-options.SerializerSettings.ContractResolver = new DefaultContractResolver
-{
-    NamingStrategy = new KebabCaseNamingStrategy()
-};
+// Use Pascal case
+options.SerializerOptions.PropertyNamingPolicy = null;
+options.SerializerOptions.DictionaryKeyPolicy = null;
 ```
 
-Because we copy resource properties into an intermediate object before serialization, Newtonsoft.Json annotations on properties are ignored.
+Because we copy resource properties into an intermediate object before serialization, JSON annotations such as `[JsonPropertyName]` and `[JsonIgnore]` on `[Attr]` properties are ignored.
 
 
 ## Enable ModelState Validation

docs/usage/resource-graph.md

@@ -98,4 +98,4 @@ public class MyModel : Identifiable
 }
 ```
 
-The default naming convention can be changed in [options](~/usage/options.md#custom-serializer-settings).
+The default naming convention can be changed in [options](~/usage/options.md#customize-serializer-options).

docs/usage/resources/attributes.md

@@ -14,7 +14,7 @@ public class Person : Identifiable
 
 There are two ways the exposed attribute name is determined:
 
-1. Using the configured [naming convention](~/usage/options.md#custom-serializer-settings).
+1. Using the configured [naming convention](~/usage/options.md#customize-serializer-options).
 
 2. Individually using the attribute's constructor.
 ```c#
@@ -88,9 +88,9 @@ public class Person : Identifiable
 ## Complex Attributes
 
 Models may contain complex attributes.
-Serialization of these types is done by [Newtonsoft.Json](https://www.newtonsoft.com/json),
-so you should use their APIs to specify serialization formats.
-You can also use global options to specify `JsonSerializer` configuration.
+Serialization of these types is done by [System.Text.Json](https://www.nuget.org/packages/System.Text.Json),
+so you should use their APIs to specify serialization format.
+You can also use [global options](~/usage/options.md#customize-serializer-options) to control the `JsonSerializer` behavior.
 
 ```c#
 public class Foo : Identifiable
@@ -101,7 +101,8 @@ public class Foo : Identifiable
 
 public class Bar
 {
-    [JsonProperty("compound-member")]
+    [JsonPropertyName("compound-member")]
+    [JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
     public string CompoundMember { get; set; }
 }
 ```
@@ -121,13 +122,13 @@ public class Foo : Identifiable
     {
         get
         {
-            return Bar == null ? "{}" : JsonConvert.SerializeObject(Bar);
+            return Bar == null ? "{}" : JsonSerializer.Serialize(Bar);
         }
         set
         {
             Bar = string.IsNullOrWhiteSpace(value)
                 ? null
-                : JsonConvert.DeserializeObject<Bar>(value);
+                : JsonSerializer.Deserialize<Bar>(value);
         }
     }
 }

docs/usage/resources/relationships.md

@@ -38,7 +38,7 @@ The left side of this relationship is of type `Person` (public name: "persons")
 
 There are two ways the exposed relationship name is determined:
 
-1. Using the configured [naming convention](~/usage/options.md#custom-serializer-settings).
+1. Using the configured [naming convention](~/usage/options.md#customize-serializer-options).
 
 2. Individually using the attribute's constructor.
 ```c#

docs/usage/routing.md

@@ -45,7 +45,7 @@ The exposed name of the resource ([which can be customized](~/usage/resource-gra
 
 ### Non-JSON:API controllers
 
-If a controller does not inherit from `JsonApiController<TResource>`, the [configured naming convention](~/usage/options.md#custom-serializer-settings) is applied to the name of the controller.
+If a controller does not inherit from `JsonApiController<TResource>`, the [configured naming convention](~/usage/options.md#customize-serializer-options) is applied to the name of the controller.
 
 ```c#
 public class OrderLineController : ControllerBase