diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 3fdc4f4..1521e5c 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -36,14 +36,14 @@ jobs:
 
     - name: Explicit NUnit test
       run: |
-        cp tests/UnitTestEx.Api/bin/Debug/net6.0/UnitTestEx.Api.deps.json tests/UnitTestEx.NUnit.Test/bin/Debug/net6.0
-        cd tests/UnitTestEx.NUnit.Test/bin/Debug/net6.0
+        cp tests/UnitTestEx.Api/bin/Debug/net8.0/UnitTestEx.Api.deps.json tests/UnitTestEx.NUnit.Test/bin/Debug/net8.0
+        cd tests/UnitTestEx.NUnit.Test/bin/Debug/net8.0
         dotnet test UnitTestEx.NUnit.Test.dll --no-build --verbosity normal
 
     - name: Explicit Xunit test
       run: |
-        cp tests/UnitTestEx.Api/bin/Debug/net6.0/UnitTestEx.Api.deps.json tests/UnitTestEx.Xunit.Test/bin/Debug/net6.0
-        cd tests/UnitTestEx.Xunit.Test/bin/Debug/net6.0
+        cp tests/UnitTestEx.Api/bin/Debug/net8.0/UnitTestEx.Api.deps.json tests/UnitTestEx.Xunit.Test/bin/Debug/net8.0
+        cd tests/UnitTestEx.Xunit.Test/bin/Debug/net8.0
         dotnet test UnitTestEx.Xunit.Test.dll --no-build --verbosity normal --tests MockHttpClientTest
         dotnet test UnitTestEx.Xunit.Test.dll --no-build --verbosity normal --tests PersonFunctionTest
         dotnet test UnitTestEx.Xunit.Test.dll --no-build --verbosity normal --tests ProductFunctionTest
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 511f357..f88c60b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,9 @@
 
 Represents the **NuGet** versions.
 
+## v5.5.0
+- *Enhancement:* The `GenericTester` where using `.NET8.0` and above will leverage the new `IHostApplicationBuilder` versus existing `IHostBuilder` (see Microsoft [documentation](https://learn.microsoft.com/en-us/dotnet/core/extensions/generic-host) and [recommendation](https://github.com/dotnet/runtime/discussions/81090#discussioncomment-4784551)). Additionally, if a `TEntryPoint` is specified with a method signature of `public void ConfigureApplication(IHostApplicationBuilder builder)` then this will be automatically invoked during host instantiation. This is a non-breaking change as largely internal.
+
 ## v5.4.6
 - *Fixed:* Added `TestFrameworkImplementor.SetLocalCreateFactory` to Xunit `ApiTestFixture` constructor to ensure set correctly for the `OnConfiguration` method override.
 
diff --git a/Common.targets b/Common.targets
index d2da746..f89c20a 100644
--- a/Common.targets
+++ b/Common.targets
@@ -1,6 +1,6 @@
 <Project>
 	<PropertyGroup>
-		<Version>5.4.6</Version>
+		<Version>5.5.0</Version>
 		<LangVersion>preview</LangVersion>
 		<Authors>Avanade</Authors>
 		<Company>Avanade</Company>
diff --git a/README.md b/README.md
index f0f2611..04cb91a 100644
--- a/README.md
+++ b/README.md
@@ -113,6 +113,20 @@ test.Run<Gin, int>(gin => gin.Pour())
     .AssertValue(1);
 ```
 
+Additionally, where the `TEntryPoint` is specified and implements `ConfigureApplication` (`.NET8.0` or above) this will be invoked automatically to perform any additional configuration. 
+
+``` csharp
+using var test = GenericTester.Create<Startup>();
+test.Run<Gin, int>(gin => gin.Pour())
+    .AssertSuccess()
+    .AssertValue(1);
+
+public class Startup
+{
+    public void ConfigureApplication(IHostApplicationBuilder builder) => builder.Services.AddSingleton<Gin>();
+}
+```
+
 <br/>
 
 ## DI Mocking
diff --git a/src/UnitTestEx/Generic/GenericTesterCore.cs b/src/UnitTestEx/Generic/GenericTesterCore.cs
index 4cdc647..4f37ffc 100644
--- a/src/UnitTestEx/Generic/GenericTesterCore.cs
+++ b/src/UnitTestEx/Generic/GenericTesterCore.cs
@@ -5,6 +5,7 @@
 using Microsoft.Extensions.Hosting;
 using Microsoft.Extensions.Logging;
 using System;
+using System.Reflection;
 using UnitTestEx.Abstractions;
 using UnitTestEx.Expectations;
 using UnitTestEx.Hosting;
@@ -58,7 +59,56 @@ private IHost GetHost()
 
                 var ep = new EntryPoint(Activator.CreateInstance<TEntryPoint>());
 
-                return _host ??= new HostBuilder()
+#if NET8_0_OR_GREATER
+                var settings = new HostApplicationBuilderSettings
+                {
+                    EnvironmentName = TestSetUp.Environment,
+                    ContentRootPath = Environment.CurrentDirectory
+                };
+
+                var builder = Host.CreateApplicationBuilder(settings);
+                builder.Logging.SetMinimumLevel(SetUp.MinimumLogLevel).ClearProviders().AddProvider(LoggerProvider);
+
+                if (ep.HasConfigureHostConfiguration)
+                    ep.ConfigureHostConfiguration(builder.Configuration);
+
+                builder.Configuration.AddJsonFile("appsettings.json", optional: true)
+                                     .AddJsonFile($"appsettings.{TestSetUp.Environment.ToLowerInvariant()}.json", optional: true);
+
+                if (ep.HasConfigureAppConfiguration)
+                {
+                    var fi = builder.GetType().GetField("_hostBuilderContext", BindingFlags.Instance | BindingFlags.NonPublic);
+                    if (fi is not null)
+                    {
+                        var hbc = (HostBuilderContext)fi.GetValue(builder)!;
+                        ep.ConfigureAppConfiguration(hbc, builder.Configuration);
+                    }
+                }
+
+                builder.Configuration.AddJsonFile("appsettings.unittest.json", optional: true)
+                                     .AddEnvironmentVariables();
+
+                if (AdditionalConfiguration != null)
+                    builder.Configuration.AddInMemoryCollection(AdditionalConfiguration);
+
+                if (ep.HasConfigureServices)
+                    ep.ConfigureServices(builder.Services);
+
+                if (ep.HasConfigureApplication)
+                    ep.ConfigureApplication(builder);
+
+                builder.Services.ReplaceScoped(_ => SharedState);
+
+                foreach (var tec in TestSetUp.Extensions)
+                    tec.ConfigureServices(this, builder.Services);
+
+                SetUp.ConfigureServices?.Invoke(builder.Services);
+                AddConfiguredServices(builder.Services);
+
+                _host = builder.Build();
+                return _host;
+#else
+                return _host ??= Host.CreateDefaultBuilder()
                     .UseEnvironment(TestSetUp.Environment)
                     .ConfigureLogging((lb) => { lb.SetMinimumLevel(SetUp.MinimumLogLevel); lb.ClearProviders(); lb.AddProvider(LoggerProvider); })
                     .ConfigureHostConfiguration(cb =>
@@ -88,6 +138,7 @@ private IHost GetHost()
                         SetUp.ConfigureServices?.Invoke(sc);
                         AddConfiguredServices(sc);
                     }).Build();
+#endif
             }
         }
 
diff --git a/src/UnitTestEx/Hosting/EntryPoint.cs b/src/UnitTestEx/Hosting/EntryPoint.cs
index 86f16e2..34ce68c 100644
--- a/src/UnitTestEx/Hosting/EntryPoint.cs
+++ b/src/UnitTestEx/Hosting/EntryPoint.cs
@@ -18,6 +18,9 @@ public class EntryPoint
         private readonly MethodInfo? _mi1;
         private readonly MethodInfo? _mi2;
         private readonly MethodInfo? _mi3;
+#if NET8_0_OR_GREATER
+        private readonly MethodInfo? _mi4;
+#endif
 
         /// <summary>
         /// Initializes a new instance of the <see cref="EntryPoint"/> class.
@@ -29,28 +32,62 @@ public EntryPoint(object instance)
             _mi1 = instance.GetType().GetMethod(nameof(ConfigureAppConfiguration), BindingFlags.Instance | BindingFlags.Public, [typeof(HostBuilderContext), typeof(IConfigurationBuilder)]);
             _mi2 = instance.GetType().GetMethod(nameof(ConfigureHostConfiguration), BindingFlags.Instance | BindingFlags.Public, [typeof(IConfigurationBuilder)]);
             _mi3 = instance.GetType().GetMethod(nameof(ConfigureServices), BindingFlags.Instance | BindingFlags.Public, [typeof(IServiceCollection)]);
+            _mi3 = instance.GetType().GetMethod(nameof(ConfigureServices), BindingFlags.Instance | BindingFlags.Public, [typeof(IServiceCollection)]);
+#if NET8_0_OR_GREATER
+            _mi4 = instance.GetType().GetMethod(nameof(ConfigureApplication), BindingFlags.Instance | BindingFlags.Public, [typeof(IHostApplicationBuilder)]);
+#endif
         }
 
+        /// <summary>
+        /// Indicates whether the <see cref="ConfigureAppConfiguration"/> has been defined on the entry point instance.
+        /// </summary>
+        public bool HasConfigureAppConfiguration => _mi1 is not null;
+
+        /// <summary>
+        /// Indicates whether the <see cref="ConfigureHostConfiguration"/> has been defined on the entry point instance.
+        /// </summary>
+        public bool HasConfigureHostConfiguration => _mi2 is not null;
+
+        /// <summary>
+        /// Indicates whether the <see cref="ConfigureServices"/> has been defined on the entry point instance.
+        /// </summary>
+        public bool HasConfigureServices => _mi3 is not null;
+
+#if NET8_0_OR_GREATER
+        /// <summary>
+        /// Indicates whether the <see cref="ConfigureApplication"/> has been defined on the entry point instance.
+        /// </summary>
+        public bool HasConfigureApplication => _mi4 is not null;
+#endif
+
         /// <summary>
         /// Sets up the configuration for the remainder of the build process and application.
         /// </summary>
         /// <param name="context"></param>
         /// <param name="config"></param>
         /// <remarks>This is intended to be invoked by the <see cref="IHostBuilder.ConfigureAppConfiguration(System.Action{HostBuilderContext, IConfigurationBuilder})"/>.</remarks>
-        public void ConfigureAppConfiguration(HostBuilderContext context, IConfigurationBuilder config) => _mi1?.Invoke(_instance, new object[] { context, config });
+        public void ConfigureAppConfiguration(HostBuilderContext context, IConfigurationBuilder config) => _mi1?.Invoke(_instance, [context, config]);
 
         /// <summary>
         /// Sets up the configuration for the builder itself to initialize the <see cref="IHostEnvironment"/>.
         /// </summary>
         /// <param name="config">The <see cref="IConfigurationBuilder"/>.</param>
         /// <remarks>This is intended to be invoked by the <see cref="IHostBuilder.ConfigureHostConfiguration(System.Action{IConfigurationBuilder})"/>.</remarks>
-        public void ConfigureHostConfiguration(IConfigurationBuilder config) => _mi2?.Invoke(_instance, new object[] { config });
+        public void ConfigureHostConfiguration(IConfigurationBuilder config) => _mi2?.Invoke(_instance, [config]);
 
         /// <summary>
         /// Adds services to the container.
         /// </summary>
         /// <param name="services">The <see cref="IServiceCollection"/>.</param>
         /// <remarks>This is intended to be invoked by the <see cref="IHostBuilder.ConfigureServices(System.Action{HostBuilderContext, IServiceCollection})"/>.</remarks>
-        public void ConfigureServices(IServiceCollection services) => _mi3?.Invoke(_instance, new object[] { services });
+        public void ConfigureServices(IServiceCollection services) => _mi3?.Invoke(_instance, [services]);
+
+#if NET8_0_OR_GREATER
+        /// <summary>
+        /// Enables further configuration of the <see cref="IHostApplicationBuilder"/> after it has been created/pre-configured.
+        /// </summary>
+        /// <param name="builder">The <see cref="IHostApplicationBuilder"/></param>
+        public void ConfigureApplication(IHostApplicationBuilder builder) => _mi4?.Invoke(_instance, [builder]);
+#endif
     }
 }
\ No newline at end of file
diff --git a/tests/UnitTestEx.Api/Controllers/PersonController.cs b/tests/UnitTestEx.Api/Controllers/PersonController.cs
index d42b51e..a4d8fa5 100644
--- a/tests/UnitTestEx.Api/Controllers/PersonController.cs
+++ b/tests/UnitTestEx.Api/Controllers/PersonController.cs
@@ -44,7 +44,7 @@ public IActionResult Get(int id)
         [HttpGet("")]
         public IActionResult GetByArgs(string firstName, string lastName, [FromQuery] List<int> id = default)
         {
-            return new ObjectResult($"{firstName}-{lastName}-{string.Join(",", id)}");
+            return new ObjectResult($"{firstName}-{lastName}-{(id is null ? "" : string.Join(",", id))}");
         }
 
         [HttpPost("{id}")]
diff --git a/tests/UnitTestEx.Api/UnitTestEx.Api.csproj b/tests/UnitTestEx.Api/UnitTestEx.Api.csproj
index 0e5f699..aca444e 100644
--- a/tests/UnitTestEx.Api/UnitTestEx.Api.csproj
+++ b/tests/UnitTestEx.Api/UnitTestEx.Api.csproj
@@ -1,14 +1,21 @@
 <Project Sdk="Microsoft.NET.Sdk.Web">
 
   <PropertyGroup>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFrameworks>net6.0;net8.0</TargetFrameworks>
     <PreserveCompilationContext>true</PreserveCompilationContext>
     <LangVersion>latest</LangVersion>
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.AspNetCore.Mvc.NewtonsoftJson" Version="6.0.18" />
     <PackageReference Include="Newtonsoft.Json" Version="13.0.3" />
   </ItemGroup>
 
+  <ItemGroup Condition="'$(TargetFramework)' == 'net8.0'">
+    <PackageReference Include="Microsoft.AspNetCore.Mvc.NewtonsoftJson" Version="8.0.14" />
+  </ItemGroup>
+
+  <ItemGroup Condition="'$(TargetFramework)' == 'net6.0'">
+    <PackageReference Include="Microsoft.AspNetCore.Mvc.NewtonsoftJson" Version="6.0.18" />
+  </ItemGroup>
+
 </Project>
diff --git a/tests/UnitTestEx.NUnit.Test/Other/GenericTest.cs b/tests/UnitTestEx.NUnit.Test/Other/GenericTest.cs
index 749565f..890b70c 100644
--- a/tests/UnitTestEx.NUnit.Test/Other/GenericTest.cs
+++ b/tests/UnitTestEx.NUnit.Test/Other/GenericTest.cs
@@ -1,5 +1,6 @@
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Hosting;
 using NUnit.Framework;
 using System;
 using System.Threading.Tasks;
@@ -39,7 +40,7 @@ public void Run_Exception()
         [Test]
         public void Run_Service()
         {
-            using var test = GenericTester.Create().ConfigureServices(services => services.AddSingleton<Gin>());
+            using var test = GenericTester.Create<EntryPoint>();
 
             test.Run<Gin, int>(gin => gin.Pour())
                 .AssertSuccess()
@@ -83,4 +84,15 @@ public void Shake() { }
         public int Pour() => 1;
         public Task<int> PourAsync() => Task.FromResult(1);
     }
+
+    public class EntryPoint
+    {
+        //public void ConfigureAppConfiguration(HostBuilderContext context, IConfigurationBuilder config) { }
+
+        //public void ConfigureHostConfiguration(IConfigurationBuilder config) { }
+
+        //public void ConfigureServices(IServiceCollection services) { }
+
+        public void ConfigureApplication(IHostApplicationBuilder builder) => builder.Services.AddSingleton<Gin>();
+    }
 }
\ No newline at end of file
diff --git a/tests/UnitTestEx.NUnit.Test/UnitTestEx.NUnit.Test.csproj b/tests/UnitTestEx.NUnit.Test/UnitTestEx.NUnit.Test.csproj
index dd8a2d6..914a231 100644
--- a/tests/UnitTestEx.NUnit.Test/UnitTestEx.NUnit.Test.csproj
+++ b/tests/UnitTestEx.NUnit.Test/UnitTestEx.NUnit.Test.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFramework>net8.0</TargetFramework>
     <IsPackable>false</IsPackable>
     <LangVersion>preview</LangVersion>
   </PropertyGroup>
diff --git a/tests/UnitTestEx.Xunit.Test/UnitTestEx.Xunit.Test.csproj b/tests/UnitTestEx.Xunit.Test/UnitTestEx.Xunit.Test.csproj
index a255700..17c30c9 100644
--- a/tests/UnitTestEx.Xunit.Test/UnitTestEx.Xunit.Test.csproj
+++ b/tests/UnitTestEx.Xunit.Test/UnitTestEx.Xunit.Test.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFramework>net8.0</TargetFramework>
 
     <IsPackable>false</IsPackable>
   </PropertyGroup>