diff --git a/src/modules/Elsa.Expressions/Helpers/ObjectConverter.cs b/src/modules/Elsa.Expressions/Helpers/ObjectConverter.cs
index 19cac840c..ed205dae8 100644
--- a/src/modules/Elsa.Expressions/Helpers/ObjectConverter.cs
+++ b/src/modules/Elsa.Expressions/Helpers/ObjectConverter.cs
@@ -24,11 +24,6 @@ public static class ObjectConverter
             return value;
 
         var options = serializerOptions ?? new JsonSerializerOptions();
-        options.SetupExtensions().SetReferenceHandling(ReferenceHandling.Preserve);
-        var registry = options.GetDiscriminatorConventionRegistry();
-        registry.ClearConventions();
-        registry.RegisterConvention(new DefaultDiscriminatorConvention<string>(options, "_type"));
-
         options.PropertyNamingPolicy = JsonNamingPolicy.CamelCase;
         options.ReferenceHandler = ReferenceHandler.Preserve;
         options.PropertyNameCaseInsensitive = true;
diff --git a/src/modules/Elsa.Http/Activities/HttpEndpoint.cs b/src/modules/Elsa.Http/Activities/HttpEndpoint.cs
index 9160c4039..6849af1c8 100644
--- a/src/modules/Elsa.Http/Activities/HttpEndpoint.cs
+++ b/src/modules/Elsa.Http/Activities/HttpEndpoint.cs
@@ -38,23 +38,28 @@ public class HttpEndpoint : Trigger<HttpRequestModel>
     )]
     public Input<string?> Policy { get; set; } = new(default(string?));
 
-    protected override IEnumerable<object> GetTriggerPayload(TriggerIndexingContext context) => GetBookmarkPayload(context.ExpressionExecutionContext);
+    /// <inheritdoc />
+    protected override IEnumerable<object> GetTriggerPayloads(TriggerIndexingContext context) => GetBookmarkPayloads(context.ExpressionExecutionContext);
 
-    protected override void Execute(ActivityExecutionContext context)
+    /// <inheritdoc />
+    protected override async ValueTask ExecuteAsync(ActivityExecutionContext context)
     {
         // If we did not receive external input, it means we are just now encountering this activity and we need to block execution by creating a bookmark.
         if (!context.TryGetInput<HttpRequestModel>(InputKey, out var request))
         {
             // Create bookmarks for when we receive the expected HTTP request.
-            context.CreateBookmarks(GetBookmarkPayload(context.ExpressionExecutionContext));
+            context.CreateBookmarks(GetBookmarkPayloads(context.ExpressionExecutionContext));
             return;
         }
 
         // Provide the received HTTP request as output.
         context.Set(Result, request);
+        
+        // Complete.
+        await context.CompleteActivityAsync();
     }
 
-    private IEnumerable<object> GetBookmarkPayload(ExpressionExecutionContext context)
+    private IEnumerable<object> GetBookmarkPayloads(ExpressionExecutionContext context)
     {
         // Generate bookmark data for path and selected methods.
         var path = context.Get(Path);
diff --git a/src/modules/Elsa.Http/Activities/SendHttpRequest.cs b/src/modules/Elsa.Http/Activities/SendHttpRequest.cs
index 211c0baf0..3584e3a0a 100644
--- a/src/modules/Elsa.Http/Activities/SendHttpRequest.cs
+++ b/src/modules/Elsa.Http/Activities/SendHttpRequest.cs
@@ -11,7 +11,7 @@ using HttpRequestHeaders = Elsa.Http.Models.HttpRequestHeaders;
 
 namespace Elsa.Http;
 
-[Activity("Elsa", "HTTP", "Send Http Request.", DisplayName = "Send HTTP Request", Kind = ActivityKind.Task)]
+[Activity("Elsa", "HTTP", "Send Http Request.", DisplayName = "HTTP Request", Kind = ActivityKind.Task)]
 public class SendHttpRequest : Activity
 {
     [Input] public Input<Uri?> Url { get; set; } = default!;
diff --git a/src/modules/Elsa.Http/Elsa.Http.csproj b/src/modules/Elsa.Http/Elsa.Http.csproj
index 294346280..7e0ec05c0 100644
--- a/src/modules/Elsa.Http/Elsa.Http.csproj
+++ b/src/modules/Elsa.Http/Elsa.Http.csproj
@@ -12,7 +12,7 @@
     </PropertyGroup>
 
     <ItemGroup>
-        <PackageReference Include="Microsoft.AspNetCore.Authorization" Version="6.0.3" />
+        <PackageReference Include="Microsoft.AspNetCore.Authorization" Version="6.0.11" />
         <PackageReference Include="Microsoft.AspNetCore.Http" Version="2.2.2" />
         <PackageReference Include="Microsoft.AspNetCore.Http.Extensions" Version="2.2.0" />
         <PackageReference Include="Microsoft.AspNetCore.Routing" Version="2.2.2" />
diff --git a/src/modules/Elsa.Http/Extensions/DependencyInjectionExtensions.cs b/src/modules/Elsa.Http/Extensions/ModuleExtensions.cs
similarity index 86%
rename from src/modules/Elsa.Http/Extensions/DependencyInjectionExtensions.cs
rename to src/modules/Elsa.Http/Extensions/ModuleExtensions.cs
index e3136bc53..650a17703 100644
--- a/src/modules/Elsa.Http/Extensions/DependencyInjectionExtensions.cs
+++ b/src/modules/Elsa.Http/Extensions/ModuleExtensions.cs
@@ -4,7 +4,7 @@ using Elsa.Http.Features;
 // ReSharper disable once CheckNamespace
 namespace Microsoft.Extensions.DependencyInjection;
 
-public static class DependencyInjectionExtensions
+public static class ModuleExtensions
 {
     public static IModule UseHttp(this IModule module, Action<HttpFeature>? configure = default)
     {
diff --git a/src/modules/Elsa.Http/Features/HttpFeature.cs b/src/modules/Elsa.Http/Features/HttpFeature.cs
index bd3f79a78..c6572a7e9 100644
--- a/src/modules/Elsa.Http/Features/HttpFeature.cs
+++ b/src/modules/Elsa.Http/Features/HttpFeature.cs
@@ -1,4 +1,6 @@
+using Elsa.Common.Features;
 using Elsa.Features.Abstractions;
+using Elsa.Features.Attributes;
 using Elsa.Features.Services;
 using Elsa.Http.ContentWriters;
 using Elsa.Http.Handlers;
@@ -11,6 +13,7 @@ using Microsoft.Extensions.DependencyInjection;
 
 namespace Elsa.Http.Features;
 
+[DependsOn(typeof(MemoryCacheFeature))]
 public class HttpFeature : FeatureBase
 {
     public HttpFeature(IModule module) : base(module)
diff --git a/src/modules/Elsa.Http/Models/HttpEndpointBookmarkPayload.cs b/src/modules/Elsa.Http/Models/HttpEndpointBookmarkPayload.cs
index f546aa859..666316bdf 100644
--- a/src/modules/Elsa.Http/Models/HttpEndpointBookmarkPayload.cs
+++ b/src/modules/Elsa.Http/Models/HttpEndpointBookmarkPayload.cs
@@ -1,3 +1,5 @@
+using System.Text.Json.Serialization;
+
 namespace Elsa.Http.Models;
 
 public record HttpEndpointBookmarkPayload
@@ -5,6 +7,11 @@ public record HttpEndpointBookmarkPayload
     private readonly string _path = default!;
     private readonly string _method = default!;
 
+    [JsonConstructor]
+    public HttpEndpointBookmarkPayload()
+    {
+    }
+    
     public HttpEndpointBookmarkPayload(string path, string method)
     {
         Path = path;
diff --git a/src/modules/Elsa.Http/Models/HttpRequestModel.cs b/src/modules/Elsa.Http/Models/HttpRequestModel.cs
index 2d56d60d8..ceb8c1174 100644
--- a/src/modules/Elsa.Http/Models/HttpRequestModel.cs
+++ b/src/modules/Elsa.Http/Models/HttpRequestModel.cs
@@ -1,3 +1,5 @@
+using System.Text.Json.Serialization;
+
 namespace Elsa.Http.Models;
 
 public record HttpRequestModel(
@@ -7,4 +9,14 @@ public record HttpRequestModel(
     IDictionary<string, string> QueryString,
     IDictionary<string, object> RouteValues,
     IDictionary<string, string> Headers
-);
\ No newline at end of file
+)
+{
+    
+    /// <summary>
+    /// Constructor used for deserialization.
+    /// </summary>
+    [JsonConstructor]
+    public HttpRequestModel() : this(default!, default!, default!, default!, default!, default!)
+    {
+    }
+}
\ No newline at end of file
diff --git a/src/modules/Elsa.Identity/Extensions/ModuleExtensions.cs b/src/modules/Elsa.Identity/Extensions/ModuleExtensions.cs
new file mode 100644
index 000000000..3af6e8451
--- /dev/null
+++ b/src/modules/Elsa.Identity/Extensions/ModuleExtensions.cs
@@ -0,0 +1,19 @@
+using Elsa.Features.Services;
+using Elsa.Identity.Features;
+
+namespace Elsa.Identity.Extensions;
+
+/// <summary>
+/// Extensions for <see cref="IModule"/> that installs the <see cref="IdentityFeature"/> feature.
+/// </summary>
+public static class ModuleExtensions
+{
+    /// <summary>
+    /// Installs & configures the <see cref="IdentityFeature"/> feature.
+    /// </summary>
+    public static IModule UseIdentity(this IModule module, Action<IdentityFeature>? configure = default)
+    {
+        module.Configure(configure);
+        return module;
+    }
+}
\ No newline at end of file
diff --git a/src/modules/Elsa.ProtoActor/Implementations/ProtoActorWorkflowRuntime.cs b/src/modules/Elsa.ProtoActor/Implementations/ProtoActorWorkflowRuntime.cs
index 4166f91ce..75f9c865f 100644
--- a/src/modules/Elsa.ProtoActor/Implementations/ProtoActorWorkflowRuntime.cs
+++ b/src/modules/Elsa.ProtoActor/Implementations/ProtoActorWorkflowRuntime.cs
@@ -213,7 +213,7 @@ public class ProtoActorWorkflowRuntime : IWorkflowRuntime
             var storeBookmarkRequest = new StoreBookmarksRequest
             {
                 WorkflowInstanceId = instanceId,
-                CorrelationId = correlationId
+                CorrelationId = correlationId.EmptyIfNull()
             };
 
             storeBookmarkRequest.BookmarkIds.AddRange(groupedBookmark.Select(x => x.Id));
diff --git a/src/modules/Elsa.Workflows.Core/Behaviors/ScheduledChildCallbackBehavior.cs b/src/modules/Elsa.Workflows.Core/Behaviors/ScheduledChildCallbackBehavior.cs
index a1bef8058..5667467c9 100644
--- a/src/modules/Elsa.Workflows.Core/Behaviors/ScheduledChildCallbackBehavior.cs
+++ b/src/modules/Elsa.Workflows.Core/Behaviors/ScheduledChildCallbackBehavior.cs
@@ -35,23 +35,5 @@ public class ScheduledChildCallbackBehavior : Behavior
         {
             await callbackEntry.CompletionCallback(activityExecutionContext, childActivityExecutionContext);
         }
-        else
-        {
-            var ports = Owner.GetType().GetProperties().Where(x => typeof(IActivity).IsAssignableFrom(x.PropertyType)).ToList();
-
-            var portQuery =
-                from p in ports
-                let i = (IActivity)p.GetValue(Owner)
-                where i == childActivity
-                select new { PortProperty = p, PortActivity = i };
-
-            var port = portQuery.FirstOrDefault();
-
-            if (port == null)
-                return;
-
-            var portName = port.PortProperty.GetCustomAttribute<PortAttribute>()?.Name ?? port.PortProperty.Name;
-            await activityExecutionContext.CompleteActivityWithOutcomesAsync(portName);
-        }
     }
 }
\ No newline at end of file
diff --git a/src/modules/Elsa.Workflows.Core/Extensions/ActivityExecutionContextExtensions.cs b/src/modules/Elsa.Workflows.Core/Extensions/ActivityExecutionContextExtensions.cs
index a95f2f824..62766d57a 100644
--- a/src/modules/Elsa.Workflows.Core/Extensions/ActivityExecutionContextExtensions.cs
+++ b/src/modules/Elsa.Workflows.Core/Extensions/ActivityExecutionContextExtensions.cs
@@ -218,13 +218,18 @@ public static class ActivityExecutionContextExtensions
         await context.SendSignalAsync(new ActivityCompleted(result));
 
         // Remove the context.
-        context.WorkflowExecutionContext.ActivityExecutionContexts.Remove(context);
+        context.WorkflowExecutionContext.RemoveActivityExecutionContext(context);
     }
 
     /// <summary>
     /// Complete the current activity with the specified outcome.
     /// </summary>
     public static ValueTask CompleteActivityWithOutcomesAsync(this ActivityExecutionContext context, params string[] outcomes) => context.CompleteActivityAsync(new Outcomes(outcomes));
+    
+    /// <summary>
+    /// Complete the current composite activity with the specified outcome.
+    /// </summary>
+    public static async ValueTask CompleteCompositeAsync(this ActivityExecutionContext context, params string[] outcomes) => await context.SendSignalAsync(new CompleteCompositeSignal(new Outcomes(outcomes)));
 
     /// <summary>
     /// Cancel the activity. For blocking activities, it means their bookmarks will be removed. For job activities, the background work will be cancelled.
diff --git a/src/modules/Elsa.Workflows.Core/Extensions/WorkflowExecutionContextExtensions.cs b/src/modules/Elsa.Workflows.Core/Extensions/WorkflowExecutionContextExtensions.cs
index 635ac98a7..23c5736b7 100644
--- a/src/modules/Elsa.Workflows.Core/Extensions/WorkflowExecutionContextExtensions.cs
+++ b/src/modules/Elsa.Workflows.Core/Extensions/WorkflowExecutionContextExtensions.cs
@@ -15,7 +15,7 @@ public static class WorkflowExecutionContextExtensions
         var list = contexts.ToList();
 
         // Remove each context.
-        foreach (var context in list) workflowExecutionContext.ActivityExecutionContexts.Remove(context);
+        foreach (var context in list) workflowExecutionContext.RemoveActivityExecutionContext(context);
     }
 
     /// <summary>
diff --git a/src/modules/Elsa.Workflows.Core/Implementations/ActivityInvoker.cs b/src/modules/Elsa.Workflows.Core/Implementations/ActivityInvoker.cs
index 2f983ef0d..516c40a96 100644
--- a/src/modules/Elsa.Workflows.Core/Implementations/ActivityInvoker.cs
+++ b/src/modules/Elsa.Workflows.Core/Implementations/ActivityInvoker.cs
@@ -31,7 +31,7 @@ public class ActivityInvoker : IActivityInvoker
         }
 
         // Add the activity context to the workflow context.
-        workflowExecutionContext.ActivityExecutionContexts.Add(activityExecutionContext);
+        workflowExecutionContext.AddActivityExecutionContext(activityExecutionContext);
 
         // Execute the activity execution pipeline.
         await InvokeAsync(activityExecutionContext);
diff --git a/src/modules/Elsa.Workflows.Core/Implementations/DefaultWorkflowExecutionContextFactory.cs b/src/modules/Elsa.Workflows.Core/Implementations/DefaultWorkflowExecutionContextFactory.cs
index c7b13d1d0..ee9fdd944 100644
--- a/src/modules/Elsa.Workflows.Core/Implementations/DefaultWorkflowExecutionContextFactory.cs
+++ b/src/modules/Elsa.Workflows.Core/Implementations/DefaultWorkflowExecutionContextFactory.cs
@@ -47,7 +47,18 @@ public class DefaultWorkflowExecutionContextFactory : IWorkflowExecutionContextF
         var scheduler = _schedulerFactory.CreateScheduler();
 
         // Setup a workflow execution context.
-        var workflowExecutionContext = new WorkflowExecutionContext(_serviceProvider, instanceId, correlationId, workflow, graph, scheduler, input, executeActivityDelegate, triggerActivityId, cancellationToken);
+        var workflowExecutionContext = new WorkflowExecutionContext(
+            _serviceProvider, 
+            instanceId, 
+            correlationId, 
+            workflow, 
+            graph, 
+            scheduler, 
+            input, 
+            executeActivityDelegate, 
+            triggerActivityId, 
+            default, 
+            cancellationToken);
 
         // Restore workflow execution context from state, if provided.
         if (workflowState != null) _workflowStateSerializer.DeserializeState(workflowExecutionContext, workflowState);
diff --git a/src/modules/Elsa.Workflows.Core/Implementations/WorkflowStateSerializer.cs b/src/modules/Elsa.Workflows.Core/Implementations/WorkflowStateSerializer.cs
index 6a8dc8493..583d729dd 100644
--- a/src/modules/Elsa.Workflows.Core/Implementations/WorkflowStateSerializer.cs
+++ b/src/modules/Elsa.Workflows.Core/Implementations/WorkflowStateSerializer.cs
@@ -97,14 +97,14 @@ public class WorkflowStateSerializer : IWorkflowStateSerializer
             var owner = workflowExecutionContext.ActivityExecutionContexts.First(x => x.Id == completionCallbackEntry.OwnerId);
             var child = workflowExecutionContext.FindNodeById(completionCallbackEntry.ChildId).Activity;
             var callbackName = completionCallbackEntry.MethodName;
-            var callbackDelegate = owner.Activity.GetActivityCompletionCallback(callbackName);
+            var callbackDelegate = !string.IsNullOrEmpty(callbackName) ? owner.Activity.GetActivityCompletionCallback(callbackName) : default;
             workflowExecutionContext.AddCompletionCallback(owner, child, callbackDelegate);
         }
     }
 
     private void SerializeCompletionCallbacks(WorkflowState state, WorkflowExecutionContext workflowExecutionContext)
     {
-        var completionCallbacks = workflowExecutionContext.CompletionCallbacks.Select(x => new CompletionCallbackState(x.Owner.Id, x.Child.Id, x.CompletionCallback.Method.Name));
+        var completionCallbacks = workflowExecutionContext.CompletionCallbacks.Select(x => new CompletionCallbackState(x.Owner.Id, x.Child.Id, x.CompletionCallback?.Method.Name));
         state.CompletionCallbacks = completionCallbacks.ToList();
     }
 
diff --git a/src/modules/Elsa.Workflows.Core/Models/WorkflowExecutionContext.cs b/src/modules/Elsa.Workflows.Core/Models/WorkflowExecutionContext.cs
index 9359510f6..6e1a1c086 100644
--- a/src/modules/Elsa.Workflows.Core/Models/WorkflowExecutionContext.cs
+++ b/src/modules/Elsa.Workflows.Core/Models/WorkflowExecutionContext.cs
@@ -14,8 +14,10 @@ public class WorkflowExecutionContext
     private readonly IServiceProvider _serviceProvider;
     private readonly IList<ActivityNode> _nodes;
     private readonly IList<ActivityCompletionCallbackEntry> _completionCallbackEntries = new List<ActivityCompletionCallbackEntry>();
+    private IList<ActivityExecutionContext> _activityExecutionContexts;
 
-    public WorkflowExecutionContext(IServiceProvider serviceProvider,
+    public WorkflowExecutionContext(
+        IServiceProvider serviceProvider,
         string id,
         string? correlationId,
         Workflow workflow,
@@ -24,6 +26,7 @@ public class WorkflowExecutionContext
         IDictionary<string, object>? input,
         ExecuteActivityDelegate? executeDelegate,
         string? triggerActivityId,
+        IEnumerable<ActivityExecutionContext>? activityExecutionContexts,
         CancellationToken cancellationToken)
     {
         _serviceProvider = serviceProvider;
@@ -33,6 +36,7 @@ public class WorkflowExecutionContext
         Id = id;
         CorrelationId = correlationId;
         _nodes = graph.Flatten().Distinct().ToList();
+        _activityExecutionContexts = activityExecutionContexts?.ToList() ?? new List<ActivityExecutionContext>();
         Scheduler = scheduler;
         Input = input ?? new Dictionary<string, object>();
         ExecuteDelegate = executeDelegate;
@@ -72,7 +76,12 @@ public class WorkflowExecutionContext
     public string? TriggerActivityId { get; set; }
     public CancellationToken CancellationToken { get; }
     public ICollection<ActivityCompletionCallbackEntry> CompletionCallbacks => new ReadOnlyCollection<ActivityCompletionCallbackEntry>(_completionCallbackEntries);
-    public ICollection<ActivityExecutionContext> ActivityExecutionContexts { get; set; } = new List<ActivityExecutionContext>();
+
+    public IReadOnlyCollection<ActivityExecutionContext> ActivityExecutionContexts
+    {
+        get => _activityExecutionContexts.ToList();
+        internal set => _activityExecutionContexts = value.ToList();
+    }
 
     /// <summary>
     /// A volatile collection of executed activity instance IDs. This collection is reset when workflow execution starts.
@@ -148,6 +157,9 @@ public class WorkflowExecutionContext
         expressionExecutionContext.TransientProperties[ExpressionExecutionContextExtensions.ActivityExecutionContextKey] = activityExecutionContext;
         return activityExecutionContext;
     }
+    
+    public void RemoveActivityExecutionContext(ActivityExecutionContext context) => _activityExecutionContexts.Remove(context);
+    public void AddActivityExecutionContext(ActivityExecutionContext context) => _activityExecutionContexts.Add(context);
 
     public async Task CancelActivityAsync(string activityId)
     {
diff --git a/src/modules/Elsa.Workflows.Core/Serialization/Converters/TypeJsonConverter.cs b/src/modules/Elsa.Workflows.Core/Serialization/Converters/TypeJsonConverter.cs
index d5f3dcbd5..7ddb706a8 100644
--- a/src/modules/Elsa.Workflows.Core/Serialization/Converters/TypeJsonConverter.cs
+++ b/src/modules/Elsa.Workflows.Core/Serialization/Converters/TypeJsonConverter.cs
@@ -39,7 +39,7 @@ public class TypeJsonConverter : JsonConverter<Type>
     public override void Write(Utf8JsonWriter writer, Type value, JsonSerializerOptions options)
     {
         // Handle collection types.
-        if (value.IsGenericType)
+        if (value.IsGenericType && value.GenericTypeArguments.Length == 1)
         {
             var elementType = value.GenericTypeArguments.First();
             var typedEnumerable = typeof(IEnumerable<>).MakeGenericType(elementType);
diff --git a/src/modules/Elsa.Workflows.Core/State/CompletionCallbackState.cs b/src/modules/Elsa.Workflows.Core/State/CompletionCallbackState.cs
index 756d3d685..199af1b74 100644
--- a/src/modules/Elsa.Workflows.Core/State/CompletionCallbackState.cs
+++ b/src/modules/Elsa.Workflows.Core/State/CompletionCallbackState.cs
@@ -13,7 +13,7 @@ public class CompletionCallbackState
     {
     }
 
-    public CompletionCallbackState(string ownerId, string childId, string methodName)
+    public CompletionCallbackState(string ownerId, string childId, string? methodName)
     {
         OwnerId = ownerId;
         ChildId = childId;
@@ -22,5 +22,5 @@ public class CompletionCallbackState
 
     public string OwnerId { get; init; } = default!;
     public string ChildId { get; init; } = default!;
-    public string MethodName { get; init; } = default!;
+    public string? MethodName { get; init; } = default!;
 }
\ No newline at end of file