diff --git a/tests/MagicOnion.Integration.Tests/MagicOnion.Integration.Tests.csproj b/tests/MagicOnion.Integration.Tests/MagicOnion.Integration.Tests.csproj
index ae27f22f5..a21ac4a77 100644
--- a/tests/MagicOnion.Integration.Tests/MagicOnion.Integration.Tests.csproj
+++ b/tests/MagicOnion.Integration.Tests/MagicOnion.Integration.Tests.csproj
@@ -4,6 +4,7 @@
     <TargetFramework>net8.0</TargetFramework>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>
+    <LangVersion>14</LangVersion>
   </PropertyGroup>
 
   <ItemGroup>
diff --git a/tests/MagicOnion.Integration.Tests/StreamingHubTest.UnknownMethodId.cs b/tests/MagicOnion.Integration.Tests/StreamingHubTest.UnknownMethodId.cs
index 818c04f88..226b86771 100644
--- a/tests/MagicOnion.Integration.Tests/StreamingHubTest.UnknownMethodId.cs
+++ b/tests/MagicOnion.Integration.Tests/StreamingHubTest.UnknownMethodId.cs
@@ -23,7 +23,7 @@ public async Task UnknownMethodId(TestStreamingHubClientFactory clientFactory)
             Assert.NotNull(ex);
             var rpcException = Assert.IsType<RpcException>(ex);
             Assert.Equal(StatusCode.Unimplemented, rpcException.Status.StatusCode);
-            Assert.Contains(factory.Logs, x => x.Contains("HubMethodNotFound\tStreamingHub method '-1'"));
+            Assert.Contains(factory.Logs.GetSnapshot(), x =>  x.Id.Name == "HubMethodNotFound" && x.Message.Contains("StreamingHub method '-1'"));
         }
     }
 
diff --git a/tests/MagicOnion.Server.InternalTesting/MagicOnion.Server.InternalTesting.csproj b/tests/MagicOnion.Server.InternalTesting/MagicOnion.Server.InternalTesting.csproj
index 3b51f3ab3..32ccd3f05 100644
--- a/tests/MagicOnion.Server.InternalTesting/MagicOnion.Server.InternalTesting.csproj
+++ b/tests/MagicOnion.Server.InternalTesting/MagicOnion.Server.InternalTesting.csproj
@@ -4,6 +4,7 @@
     <TargetFramework>net8.0</TargetFramework>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>
+    <LangVersion>14</LangVersion>
   </PropertyGroup>
 
   <ItemGroup>
diff --git a/tests/MagicOnion.Server.InternalTesting/MagicOnionApplicationFactory.cs b/tests/MagicOnion.Server.InternalTesting/MagicOnionApplicationFactory.cs
index b4d31fd62..377c2e138 100644
--- a/tests/MagicOnion.Server.InternalTesting/MagicOnionApplicationFactory.cs
+++ b/tests/MagicOnion.Server.InternalTesting/MagicOnionApplicationFactory.cs
@@ -4,6 +4,7 @@
 using System.Collections.Concurrent;
 using Microsoft.Extensions.Logging;
 using Microsoft.AspNetCore.Builder;
+using Microsoft.Extensions.Logging.Testing;
 
 namespace MagicOnion.Server.InternalTesting;
 
@@ -19,18 +20,12 @@ protected override IEnumerable<Type> GetServiceImplementationTypes()
 public abstract class MagicOnionApplicationFactory : WebApplicationFactory<Program>
 {
     public const string ItemsKey = "MagicOnionApplicationFactory.Items";
-    public ConcurrentDictionary<string, object> Items => Services.GetRequiredKeyedService<ConcurrentDictionary<string, object>>(ItemsKey);
-    public ConcurrentBag<string> Logs { get; } = new();
 
     protected override void ConfigureWebHost(IWebHostBuilder builder)
     {
         builder.ConfigureLogging(logger =>
         {
-            logger.AddFakeLogging(options =>
-            {
-                options.OutputFormatter = x => $"{x.Timestamp}\t{x.Level}\t{x.Id}\t{x.Message}\t{x.Exception}";
-                options.OutputSink = x => Logs.Add(x);
-            });
+            logger.AddFakeLogging();
         });
         builder.ConfigureServices(services =>
         {
@@ -53,18 +48,28 @@ protected virtual void OnConfigureMagicOnionBuilder(IMagicOnionServerBuilder bui
 
     public WebApplicationFactory<Program> WithMagicOnionOptions(Action<MagicOnionOptions> configure)
     {
-        return this.WithWebHostBuilder(x =>
+        return WithWebHostBuilder(builder =>
         {
-            x.ConfigureServices(services =>
+            builder.ConfigureServices(services =>
             {
                 services.Configure<MagicOnionOptions>(configure);
             });
         });
     }
+}
+
 
-    public void Initialize()
+public static class WebApplicationBuilderExtensions
+{
+    extension(WebApplicationFactory<Program> @this)
     {
-        Items.Clear();
-        Logs.Clear();
+        public ConcurrentDictionary<string, object> Items => @this.Services.GetRequiredKeyedService<ConcurrentDictionary<string, object>>(MagicOnionApplicationFactory.ItemsKey);
+        public FakeLogCollector Logs => @this.Services.GetRequiredService<FakeLogCollector>();
+
+        public void Initialize()
+        {
+            @this.Logs.Clear();
+            @this.Items.Clear();
+        }
     }
 }
diff --git a/tests/MagicOnion.Server.JsonTranscoding.Tests/MagicOnion.Server.JsonTranscoding.Tests.csproj b/tests/MagicOnion.Server.JsonTranscoding.Tests/MagicOnion.Server.JsonTranscoding.Tests.csproj
index 6321e4207..ffdcb70a4 100644
--- a/tests/MagicOnion.Server.JsonTranscoding.Tests/MagicOnion.Server.JsonTranscoding.Tests.csproj
+++ b/tests/MagicOnion.Server.JsonTranscoding.Tests/MagicOnion.Server.JsonTranscoding.Tests.csproj
@@ -6,6 +6,8 @@
     <Nullable>enable</Nullable>
 
     <IsTestProject>true</IsTestProject>
+
+    <LangVersion>14</LangVersion>
   </PropertyGroup>
 
   <ItemGroup>
diff --git a/tests/MagicOnion.Server.Redis.Tests/MagicOnion.Server.Redis.Tests.csproj b/tests/MagicOnion.Server.Redis.Tests/MagicOnion.Server.Redis.Tests.csproj
index 2bdcfb7f0..e97b4c373 100644
--- a/tests/MagicOnion.Server.Redis.Tests/MagicOnion.Server.Redis.Tests.csproj
+++ b/tests/MagicOnion.Server.Redis.Tests/MagicOnion.Server.Redis.Tests.csproj
@@ -4,6 +4,7 @@
     <TargetFramework>net8.0</TargetFramework>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>
+    <LangVersion>14</LangVersion>
   </PropertyGroup>
 
   <ItemGroup>
diff --git a/tests/MagicOnion.Server.Tests/MagicOnion.Server.Tests.csproj b/tests/MagicOnion.Server.Tests/MagicOnion.Server.Tests.csproj
index 9a0364722..df02efd3e 100644
--- a/tests/MagicOnion.Server.Tests/MagicOnion.Server.Tests.csproj
+++ b/tests/MagicOnion.Server.Tests/MagicOnion.Server.Tests.csproj
@@ -2,7 +2,7 @@
 
   <PropertyGroup>
     <TargetFramework>net8.0</TargetFramework>
-    <LangVersion>default</LangVersion>
+    <LangVersion>14</LangVersion>
     <ImplicitUsings>enable</ImplicitUsings>
 
     <!-- CS8002: Referenced assembly '{0}' does not have a strong name. -->
diff --git a/tests/MagicOnion.Server.Tests/MagicOnionMetricsTest.cs b/tests/MagicOnion.Server.Tests/MagicOnionMetricsTest.cs
index 1b85503c7..4eca54088 100644
--- a/tests/MagicOnion.Server.Tests/MagicOnionMetricsTest.cs
+++ b/tests/MagicOnion.Server.Tests/MagicOnionMetricsTest.cs
@@ -25,6 +25,7 @@ public MagicOnionMetricsTest(MagicOnionApplicationFactory<MagicOnionMetricsTestH
                 services.AddSingleton<MagicOnionMetrics>(new MagicOnionMetrics(meterFactory));
             });
         });
+        this.factory.Initialize();
     }
 
     [Fact]
diff --git a/tests/MagicOnion.Server.Tests/RawBytesResponseTest.cs b/tests/MagicOnion.Server.Tests/RawBytesResponseTest.cs
index 23a2babf5..4f042108e 100644
--- a/tests/MagicOnion.Server.Tests/RawBytesResponseTest.cs
+++ b/tests/MagicOnion.Server.Tests/RawBytesResponseTest.cs
@@ -15,6 +15,7 @@ public class RawBytesResponseTest : IClassFixture<MagicOnionApplicationFactory<R
     public RawBytesResponseTest(MagicOnionApplicationFactory<RawBytesResponseTestService> factory)
     {
         this.factory = factory.WithMagicOnionOptions(options => {});
+        this.factory.Initialize();
     }
 
     [Fact]
diff --git a/tests/MagicOnion.Server.Tests/StreamingHubConnectionEventsTest.cs b/tests/MagicOnion.Server.Tests/StreamingHubConnectionEventsTest.cs
index 7069bf4f0..2f30d3966 100644
--- a/tests/MagicOnion.Server.Tests/StreamingHubConnectionEventsTest.cs
+++ b/tests/MagicOnion.Server.Tests/StreamingHubConnectionEventsTest.cs
@@ -6,6 +6,7 @@
 using Microsoft.AspNetCore.Mvc.Testing;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.Logging.Testing;
 using NSubstitute;
 
 namespace MagicOnion.Server.Tests;
@@ -13,15 +14,11 @@ namespace MagicOnion.Server.Tests;
 public class StreamingHubConnectionEventsTest: IClassFixture<MagicOnionApplicationFactory<StreamingHubConnectionEventsTestHub>>
 {
     readonly WebApplicationFactory<Program> factory;
-    readonly ConcurrentBag<string> logs;
-    readonly ConcurrentDictionary<string, object> items;
 
     public StreamingHubConnectionEventsTest(MagicOnionApplicationFactory<StreamingHubConnectionEventsTestHub> factory)
     {
-        factory.Initialize();
         this.factory = factory;
-        this.logs = factory.Logs;
-        this.items = factory.Items;
+        this.factory.Initialize();
     }
 
     [Fact]
@@ -37,10 +34,10 @@ public async Task EventsCalled()
         await client.DisposeAsync();
         await Task.Delay(100, TestContext.Current.CancellationToken);
 
-        Assert.True((bool)items.GetValueOrDefault("OnConnecting", false));
-        Assert.True((bool)items.GetValueOrDefault("OnConnected", false));
-        Assert.True((bool)items.GetValueOrDefault("OnDisconnected", false));
-        Assert.Equal(["E/OnDisconnected", "E/OnConnected", "E/OnConnecting"], logs.Select(x => x.Split('\t')[3]).Where(x => x.StartsWith("E")));
+        Assert.True((bool)factory.Items.GetValueOrDefault("OnConnecting", false));
+        Assert.True((bool)factory.Items.GetValueOrDefault("OnConnected", false));
+        Assert.True((bool)factory.Items.GetValueOrDefault("OnDisconnected", false));
+        Assert.Equal(["E/OnConnecting", "E/OnConnected", "E/OnDisconnected"], factory.Logs.GetSnapshot().Select(x => x.Message).Where(x => x.StartsWith("E/")));
     }
 
     [Fact]
@@ -56,10 +53,11 @@ await StreamingHubClient.ConnectAsync<IStreamingHubConnectionEventsTestHub, IStr
                 option: new CallOptions(new Metadata(){ { "ThrowsRSEOnConnecting", "1" }}),
                 cancellationToken: TestContext.Current.CancellationToken));
 
+        var logSnapshot = factory.Logs.GetSnapshot();
         Assert.Equal(StatusCode.FailedPrecondition, ex.StatusCode);
-        Assert.True(logs.Any(x => x.Contains("\tE/OnConnecting\t")));
-        Assert.False(logs.Any(x => x.Contains("\tE/OnConnected\t")));
-        Assert.False(logs.Any(x => x.Contains("\tError\t")));
+        Assert.Contains(logSnapshot.Select(x => x.Message), x => x == "E/OnConnecting");
+        Assert.DoesNotContain(logSnapshot.Select(x => x.Message), x => x == "E/OnConnected");
+        Assert.DoesNotContain(logSnapshot.Select(x => x.Message), x => x == "Error");
     }
 
     [Fact]
@@ -78,11 +76,13 @@ await StreamingHubClient.ConnectAsync<IStreamingHubConnectionEventsTestHub, IStr
                 cancellationToken: TestContext.Current.CancellationToken);
 
         var ex = await Assert.ThrowsAsync<RpcException>(async () => await client.HelloAsync());
+        var logSnapshot = factory.Logs.GetSnapshot();
         Assert.Contains("StreamingHubClient has already been disconnected from the server", ex.Message);
         Assert.Equal(StatusCode.Unavailable, ex.StatusCode);
-        Assert.True(logs.Any(x => x.Contains("\tE/OnConnecting\t")));
-        Assert.True(logs.Any(x => x.Contains("\tE/OnConnected\t")));
-        Assert.False(logs.Any(x => x.Contains("\tError\t")));
+        Assert.Contains(logSnapshot.Select(x => x.Message), x => x == "E/OnConnecting");
+        Assert.Contains(logSnapshot.Select(x => x.Message), x => x == "E/OnConnected");
+        Assert.DoesNotContain(logSnapshot.Select(x => x.Message), x => x == "Error");
+
     }
 }
 
diff --git a/tests/MagicOnion.Server.Tests/StreamingHubDisconnectionTest.cs b/tests/MagicOnion.Server.Tests/StreamingHubDisconnectionTest.cs
index 0728860a7..90da056fa 100644
--- a/tests/MagicOnion.Server.Tests/StreamingHubDisconnectionTest.cs
+++ b/tests/MagicOnion.Server.Tests/StreamingHubDisconnectionTest.cs
@@ -5,20 +5,19 @@
 using MagicOnion.Server.Hubs;
 using Microsoft.AspNetCore.Mvc.Testing;
 using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.Logging.Testing;
 using NSubstitute;
 
 namespace MagicOnion.Server.Tests;
 
 public class StreamingHubDisconnectionTest : IClassFixture<MagicOnionApplicationFactory<StreamingHubDisconnectionTestHub>>
 {
-    readonly ConcurrentBag<string> logs;
     readonly WebApplicationFactory<Program> factory;
 
     public StreamingHubDisconnectionTest(MagicOnionApplicationFactory<StreamingHubDisconnectionTestHub> factory)
     {
-        factory.Initialize();
         this.factory = factory;
-        this.logs = factory.Logs;
+        this.factory.Initialize();
     }
 
     [Fact]
@@ -42,8 +41,9 @@ public async Task DisconnectWhileConsumingHubMethodQueue()
 
         await Task.Delay(500);
 
-        var doWorkAsyncCallCount = logs.Count(x => x.Contains("DoWorkAsync:Begin"));
-        var doWorkAsyncDoneCallCount = logs.Count(x => x.Contains("DoWorkAsync:Done"));
+        var logs = factory.Logs.GetSnapshot();
+        var doWorkAsyncCallCount = logs.Count(x => x.Message == "DoWorkAsync:Begin");
+        var doWorkAsyncDoneCallCount = logs.Count(x => x.Message == "DoWorkAsync:Done");
         Assert.True(doWorkAsyncCallCount < 3);
         Assert.True(doWorkAsyncCallCount == doWorkAsyncDoneCallCount);
     }
diff --git a/tests/MagicOnion.Server.Tests/StreamingHubThrowOnDisconnectTest.cs b/tests/MagicOnion.Server.Tests/StreamingHubThrowOnDisconnectTest.cs
index 9884a34fb..921c82ca4 100644
--- a/tests/MagicOnion.Server.Tests/StreamingHubThrowOnDisconnectTest.cs
+++ b/tests/MagicOnion.Server.Tests/StreamingHubThrowOnDisconnectTest.cs
@@ -7,18 +7,17 @@
 using Microsoft.AspNetCore.Mvc.Testing;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.Logging.Testing;
 using NSubstitute;
 
 namespace MagicOnion.Server.Tests;
 
 public class StreamingHubThrowOnDisconnectTest : IClassFixture<MagicOnionApplicationFactory<StreamingHubThrowOnDisconnectTestHub>>
 {
-    readonly ConcurrentBag<string> logs;
     readonly WebApplicationFactory<Program> factory;
 
     public StreamingHubThrowOnDisconnectTest(MagicOnionApplicationFactory<StreamingHubThrowOnDisconnectTestHub> factory)
     {
-        factory.Initialize();
         this.factory = factory.WithWebHostBuilder(builder =>
         {
             builder.ConfigureServices(services =>
@@ -31,7 +30,7 @@ public StreamingHubThrowOnDisconnectTest(MagicOnionApplicationFactory<StreamingH
                         (IRemoteClientResultPendingTaskRegistry)(desc.ImplementationInstance ?? desc.ImplementationFactory(sp))));
             });
         });
-        this.logs = factory.Logs;
+        this.factory.Initialize();
     }
 
     [Fact]
@@ -52,7 +51,8 @@ public async Task ThrowOnDisconnect()
 
         await Task.Delay(100);
 
-        Assert.True(logs.Any(x => x.Contains("OnDisconnected")));
+        var logs = this.factory.Logs.GetSnapshot();
+        Assert.True(logs.Any(x => x.Message == "OnDisconnected"));
         Assert.True(pendingTaskRegistry.IsDisposed);
     }
 }
diff --git a/tests/MagicOnion.Server.Tests/UnaryServiceTest.cs b/tests/MagicOnion.Server.Tests/UnaryServiceTest.cs
index 777bad478..fd5891c50 100644
--- a/tests/MagicOnion.Server.Tests/UnaryServiceTest.cs
+++ b/tests/MagicOnion.Server.Tests/UnaryServiceTest.cs
@@ -4,23 +4,24 @@
 using MagicOnion.Client;
 using MessagePack;
 using Microsoft.AspNetCore.Mvc.Testing;
+using Microsoft.Extensions.Logging.Testing;
 
 namespace MagicOnion.Server.Tests;
 
 public class UnaryServiceTest_ReturnExceptionStackTrace : IClassFixture<MagicOnionApplicationFactory<UnaryTestService>>
 {
-    readonly ConcurrentBag<string> logs;
     readonly WebApplicationFactory<Program> factory;
+    readonly FakeLogCollector logs;
 
     public UnaryServiceTest_ReturnExceptionStackTrace(MagicOnionApplicationFactory<UnaryTestService> factory)
     {
-        factory.Initialize();
         this.factory = factory.WithMagicOnionOptions(options =>
         {
             options.IsReturnExceptionStackTraceInErrorDetail = true;
         });
 
-        this.logs = factory.Logs;
+        this.factory.Initialize();
+        this.logs = this.factory.Logs;
     }
 
     [Fact]
@@ -32,7 +33,7 @@ public async Task ReturnTypeIsNilAndNonSuccessResponse()
         var ex = await Assert.ThrowsAsync<RpcException>(async () => await client.ReturnTypeIsNilAndNonSuccessResponseAsync(StatusCode.AlreadyExists));
         Assert.Equal(StatusCode.AlreadyExists, ex.StatusCode);
         Assert.Equal(nameof(IUnaryTestService.ReturnTypeIsNilAndNonSuccessResponseAsync), ex.Status.Detail);
-        Assert.Single(logs);
+        Assert.Equal(1, logs.Count);
     }
 
     [Fact]
@@ -43,7 +44,7 @@ public async Task Throw_NoParameterReturnNil()
 
         var ex = await Assert.ThrowsAsync<RpcException>(async () => await client.ThrowAsync());
         Assert.Equal(StatusCode.Unknown, ex.StatusCode);
-        Assert.Single(logs);
+        Assert.Equal(1, logs.Count);
         Assert.Contains("Something went wrong", ex.Message);
     }
 
@@ -55,7 +56,7 @@ public async Task Throw_OneParameterReturnNil()
 
         var ex = await Assert.ThrowsAsync<RpcException>(async () => await client.ThrowOneValueTypeParameterReturnNilAsync(1234));
         Assert.Equal(StatusCode.Unknown, ex.StatusCode);
-        Assert.Single(logs);
+        Assert.Equal(1, factory.Logs.Count);
         Assert.Contains("Something went wrong", ex.Message);
     }
 
@@ -67,14 +68,14 @@ public async Task Throw_TwoParameterReturnNil()
 
         var ex = await Assert.ThrowsAsync<RpcException>(async () => await client.ThrowTwoValueTypeParameterReturnNilAsync(1234, 5678));
         Assert.Equal(StatusCode.Unknown, ex.StatusCode);
-        Assert.Single(logs);
+        Assert.Equal(1, logs.Count);
         Assert.Contains("Something went wrong", ex.Message);
     }
 }
 
 public class UnaryServiceTest : IClassFixture<MagicOnionApplicationFactory<UnaryTestService>>
 {
-    readonly ConcurrentBag<string> logs;
+    readonly FakeLogCollector logs;
     readonly WebApplicationFactory<Program> factory;
 
     public UnaryServiceTest(MagicOnionApplicationFactory<UnaryTestService> factory)
@@ -92,7 +93,7 @@ public async Task Throw_NoParameterReturnNil()
 
         var ex = await Assert.ThrowsAsync<RpcException>(async () => await client.ThrowAsync());
         Assert.Equal(StatusCode.Unknown, ex.StatusCode);
-        Assert.Single(logs);
+        Assert.Single(logs.GetSnapshot());
         Assert.DoesNotContain("Something went wrong", ex.Message);
     }
 
@@ -104,7 +105,7 @@ public async Task Throw_OneParameterReturnNil()
 
         var ex = await Assert.ThrowsAsync<RpcException>(async () => await client.ThrowOneValueTypeParameterReturnNilAsync(1234));
         Assert.Equal(StatusCode.Unknown, ex.StatusCode);
-        Assert.Single(logs);
+        Assert.Single(logs.GetSnapshot());
         Assert.DoesNotContain("Something went wrong", ex.Message);
     }
 
@@ -116,7 +117,7 @@ public async Task Throw_TwoParameterReturnNil()
 
         var ex = await Assert.ThrowsAsync<RpcException>(async () => await client.ThrowTwoValueTypeParameterReturnNilAsync(1234, 5678));
         Assert.Equal(StatusCode.Unknown, ex.StatusCode);
-        Assert.Single(logs);
+        Assert.Single(logs.GetSnapshot());
         Assert.DoesNotContain("Something went wrong", ex.Message);
     }