diff --git a/src/modules/Elsa.Workflows.Core/Models/ActivityT.cs b/src/modules/Elsa.Workflows.Core/Models/ActivityT.cs
new file mode 100644
index 000000000..58e668754
--- /dev/null
+++ b/src/modules/Elsa.Workflows.Core/Models/ActivityT.cs
@@ -0,0 +1,43 @@
+using Elsa.Expressions.Models;
+using Elsa.Workflows.Core.Contracts;
+
+namespace Elsa.Workflows.Core.Models;
+
+/// <summary>
+/// Base class for custom activities that return a result.
+/// </summary>
+public abstract class Activity<T> : Activity, IActivityWithResult<T>
+{
+    /// <inheritdoc />
+    protected Activity(string? source = default, int? line = default) : base(source, line)
+    {
+    }
+
+    /// <inheritdoc />
+    protected Activity(string activityType, int version = 1, string? source = default, int? line = default) : base(activityType, version, source, line)
+    {
+    }
+
+    /// <inheritdoc />
+    protected Activity(MemoryBlockReference? output, string? source = default, int? line = default) : this(source, line)
+    {
+        if (output != null) Result = new Output<T>(output);
+    }
+
+    /// <inheritdoc />
+    protected Activity(Output<T>? output, string? source = default, int? line = default) : this(source, line)
+    {
+        Result = output;
+    }
+
+    /// <summary>
+    /// The result of the activity.
+    /// </summary>
+    public Output<T>? Result { get; set; }
+
+    Output? IActivityWithResult.Result
+    {
+        get => Result;
+        set => Result = (Output<T>?)value;
+    }
+}
\ No newline at end of file
diff --git a/src/modules/Elsa.Workflows.Core/Models/CodeActivity.cs b/src/modules/Elsa.Workflows.Core/Models/CodeActivity.cs
index 3e600fd45..b9bd7f356 100644
--- a/src/modules/Elsa.Workflows.Core/Models/CodeActivity.cs
+++ b/src/modules/Elsa.Workflows.Core/Models/CodeActivity.cs
@@ -96,37 +96,4 @@ public abstract class CodeActivity<T> : CodeActivity, IActivityWithResult<T>
         get => Result;
         set => Result = (Output<T>?)value;
     }
-}
-
-/// <summary>
-/// Base class for custom activities that return a result.
-/// </summary>
-public abstract class Activity<T> : Activity
-{
-    /// <inheritdoc />
-    protected Activity(string? source = default, int? line = default) : base(source, line)
-    {
-    }
-
-    /// <inheritdoc />
-    protected Activity(string activityType, int version = 1, string? source = default, int? line = default) : base(activityType, version, source, line)
-    {
-    }
-
-    /// <inheritdoc />
-    protected Activity(MemoryBlockReference? output, string? source = default, int? line = default) : this(source, line)
-    {
-        if (output != null) Result = new Output<T>(output);
-    }
-
-    /// <inheritdoc />
-    protected Activity(Output<T>? output, string? source = default, int? line = default) : this(source, line)
-    {
-        Result = output;
-    }
-
-    /// <summary>
-    /// The result of the activity.
-    /// </summary>
-    public Output<T>? Result { get; set; }
 }
\ No newline at end of file