diff --git a/src/Email/test/Email.Tests.csproj b/src/Email/test/Email.Tests.csproj
index ac8f2e5..7033f6d 100644
--- a/src/Email/test/Email.Tests.csproj
+++ b/src/Email/test/Email.Tests.csproj
@@ -14,6 +14,7 @@
         <PackageReference Include="FluentAssertions" />
         <PackageReference Include="Microsoft.NET.Test.Sdk" />
         <PackageReference Include="netDumbster" />
+        <PackageReference Include="NSubstitute" />
         <PackageReference Include="xunit" />
         <PackageReference Include="xunit.runner.visualstudio">
             <PrivateAssets>all</PrivateAssets>
diff --git a/src/Email/test/TestBase.cs b/src/Email/test/TestBase.cs
index 0a6a7f8..e585ead 100644
--- a/src/Email/test/TestBase.cs
+++ b/src/Email/test/TestBase.cs
@@ -1,8 +1,10 @@
 // Copyright (c) Fusonic GmbH. All rights reserved.
 // Licensed under the MIT License. See LICENSE file in the project root for license information.
 
+using System.Diagnostics;
 using Fusonic.Extensions.UnitTests;
 using Fusonic.Extensions.UnitTests.SimpleInjector;
+using MediatR;
 
 namespace Fusonic.Extensions.Email.Tests;
 
@@ -17,4 +19,9 @@ public abstract class TestBase<TFixture> : DependencyInjectionUnitTest<TFixture>
 {
     protected TestBase(TFixture fixture) : base(fixture)
     { }
+
+    /// <summary> Runs a mediator command in its own scope. Used to reduce possible side effects from test data creation and the like. </summary>
+    [DebuggerStepThrough]
+    protected Task<TResponse> SendAsync<TResponse>(IRequest<TResponse> request)
+        => ScopedAsync(() => GetInstance<IMediator>().Send(request));
 }
diff --git a/src/Hangfire/test/TestBase.cs b/src/Hangfire/test/TestBase.cs
index 04ab908..7fe37e7 100644
--- a/src/Hangfire/test/TestBase.cs
+++ b/src/Hangfire/test/TestBase.cs
@@ -1,7 +1,9 @@
 // Copyright (c) Fusonic GmbH. All rights reserved.
 // Licensed under the MIT License. See LICENSE file in the project root for license information.
 
+using System.Diagnostics;
 using Fusonic.Extensions.UnitTests.EntityFrameworkCore;
+using MediatR;
 
 namespace Fusonic.Extensions.Hangfire.Tests;
 
@@ -16,4 +18,9 @@ public abstract class TestBase<TFixture> : DatabaseUnitTest<TestDbContext, TFixt
 {
     protected TestBase(TFixture fixture) : base(fixture)
     { }
+
+    /// <summary> Runs a mediator command in its own scope. Used to reduce possible side effects from test data creation and the like. </summary>
+    [DebuggerStepThrough]
+    protected Task<TResponse> SendAsync<TResponse>(IRequest<TResponse> request)
+        => ScopedAsync(() => GetInstance<IMediator>().Send(request));
 }
\ No newline at end of file
diff --git a/src/UnitTests.EntityFrameworkCore/test/UnitTests.EntityFrameworkCore.Tests.csproj b/src/UnitTests.EntityFrameworkCore/test/UnitTests.EntityFrameworkCore.Tests.csproj
index f94fba1..fbb9d45 100644
--- a/src/UnitTests.EntityFrameworkCore/test/UnitTests.EntityFrameworkCore.Tests.csproj
+++ b/src/UnitTests.EntityFrameworkCore/test/UnitTests.EntityFrameworkCore.Tests.csproj
@@ -14,6 +14,7 @@
     </PackageReference>
     <PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" />
+    <PackageReference Include="NSubstitute" />
     <PackageReference Include="xunit" />
     <PackageReference Include="xunit.runner.visualstudio">
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
diff --git a/src/UnitTests/src/DependencyInjectionUnitTest.cs b/src/UnitTests/src/DependencyInjectionUnitTest.cs
index dd381d7..ff3020e 100644
--- a/src/UnitTests/src/DependencyInjectionUnitTest.cs
+++ b/src/UnitTests/src/DependencyInjectionUnitTest.cs
@@ -2,22 +2,15 @@
 // Licensed under the MIT License. See LICENSE file in the project root for license information.
 
 using System.Diagnostics;
-using MediatR;
 using Xunit;
 
 namespace Fusonic.Extensions.UnitTests;
 
-public abstract class DependencyInjectionUnitTest<TFixture> : IDisposable, IClassFixture<TFixture>
+public abstract class DependencyInjectionUnitTest<TFixture>(TFixture fixture) : IDisposable, IClassFixture<TFixture>
     where TFixture : class, IDependencyInjectionTestFixture
 {
-    private object currentScope;
-    protected TFixture Fixture { get; }
-
-    protected DependencyInjectionUnitTest(TFixture fixture)
-    {
-        Fixture = fixture;
-        currentScope = fixture.BeginScope();
-    }
+    private object currentScope = fixture.BeginScope();
+    protected TFixture Fixture { get; } = fixture;
 
     /// <summary> Gets an instance of the requested service. </summary>
     [DebuggerStepThrough]
@@ -28,11 +21,6 @@ protected T GetInstance<T>()
     [DebuggerStepThrough]
     protected object GetInstance(Type serviceType) => Fixture.GetInstance(currentScope, serviceType);
 
-    /// <summary> Runs a mediator command in its own scope. Used to reduce possible side effects from test data creation and the like. </summary>
-    [DebuggerStepThrough]
-    protected Task<TResponse> SendAsync<TResponse>(IRequest<TResponse> request)
-        => ScopedAsync(() => GetInstance<IMediator>().Send(request));
-
     /// <summary> <see cref="ScopedAsync{TResult}"/> </summary>
     [DebuggerStepThrough]
     protected TResult Scoped<TResult>(Func<TResult> action)
diff --git a/src/UnitTests/src/UnitTests.csproj b/src/UnitTests/src/UnitTests.csproj
index 6447d13..05a9a78 100644
--- a/src/UnitTests/src/UnitTests.csproj
+++ b/src/UnitTests/src/UnitTests.csproj
@@ -17,7 +17,6 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="MediatR" />
     <PackageReference Include="Microsoft.Extensions.Configuration" />
     <PackageReference Include="Microsoft.Extensions.Configuration.EnvironmentVariables" />
     <PackageReference Include="Microsoft.Extensions.Configuration.FileExtensions" />
@@ -25,8 +24,6 @@
     <PackageReference Include="Microsoft.Extensions.Configuration.UserSecrets" />
     <PackageReference Include="Microsoft.Extensions.DependencyInjection" />
     <PackageReference Include="Microsoft.Extensions.Logging.Abstractions" />
-    <PackageReference Include="NSubstitute" />
-    <PackageReference Include="SimpleInjector" />
     <PackageReference Include="xunit" />
   </ItemGroup>