diff --git a/framework/src/Volo.Abp.AspNetCore.Serilog/Volo.Abp.AspNetCore.Serilog.csproj b/framework/src/Volo.Abp.AspNetCore.Serilog/Volo.Abp.AspNetCore.Serilog.csproj
index 07ed436526..6874bf6b9a 100644
--- a/framework/src/Volo.Abp.AspNetCore.Serilog/Volo.Abp.AspNetCore.Serilog.csproj
+++ b/framework/src/Volo.Abp.AspNetCore.Serilog/Volo.Abp.AspNetCore.Serilog.csproj
@@ -5,6 +5,8 @@
 
     <PropertyGroup>
         <TargetFramework>net7.0</TargetFramework>
+        <Nullable>enable</Nullable>
+        <WarningsAsErrors>Nullable</WarningsAsErrors>
         <AssemblyName>Volo.Abp.AspNetCore.Serilog</AssemblyName>
         <PackageId>Volo.Abp.AspNetCore.Serilog</PackageId>
         <AssetTargetFallback>$(AssetTargetFallback);portable-net45+win8+wp8+wpa81;</AssetTargetFallback>
diff --git a/framework/src/Volo.Abp.AspNetCore.SignalR/Volo.Abp.AspNetCore.SignalR.csproj b/framework/src/Volo.Abp.AspNetCore.SignalR/Volo.Abp.AspNetCore.SignalR.csproj
index 8d427a5f21..24796d8e35 100644
--- a/framework/src/Volo.Abp.AspNetCore.SignalR/Volo.Abp.AspNetCore.SignalR.csproj
+++ b/framework/src/Volo.Abp.AspNetCore.SignalR/Volo.Abp.AspNetCore.SignalR.csproj
@@ -5,6 +5,8 @@
 
   <PropertyGroup>
     <TargetFramework>net7.0</TargetFramework>
+    <Nullable>enable</Nullable>
+    <WarningsAsErrors>Nullable</WarningsAsErrors>
     <AssemblyName>Volo.Abp.AspNetCore.SignalR</AssemblyName>
     <PackageId>Volo.Abp.AspNetCore.SignalR</PackageId>
     <AssetTargetFallback>$(AssetTargetFallback);portable-net45+win8+wp8+wpa81;</AssetTargetFallback>
diff --git a/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/AbpAspNetCoreSignalRModule.cs b/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/AbpAspNetCoreSignalRModule.cs
index 13400a7ff9..d0a9aa682d 100644
--- a/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/AbpAspNetCoreSignalRModule.cs
+++ b/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/AbpAspNetCoreSignalRModule.cs
@@ -23,7 +23,7 @@ public class AbpAspNetCoreSignalRModule : AbpModule
 {
     private static readonly MethodInfo MapHubGenericMethodInfo =
         typeof(AbpAspNetCoreSignalRModule)
-            .GetMethod("MapHub", BindingFlags.Static | BindingFlags.NonPublic);
+            .GetMethod("MapHub", BindingFlags.Static | BindingFlags.NonPublic)!;
 
     public override void PreConfigureServices(ServiceConfigurationContext context)
     {
diff --git a/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/AbpHub.cs b/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/AbpHub.cs
index 7667b80190..d97fb72421 100644
--- a/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/AbpHub.cs
+++ b/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/AbpHub.cs
@@ -14,24 +14,24 @@ namespace Volo.Abp.AspNetCore.SignalR;
 
 public abstract class AbpHub : Hub
 {
-    public IAbpLazyServiceProvider LazyServiceProvider { get; set; }
+    public IAbpLazyServiceProvider LazyServiceProvider { get; set; } = default!;
 
     [Obsolete("Use LazyServiceProvider instead.")]
-    public IServiceProvider ServiceProvider { get; set; }
+    public IServiceProvider ServiceProvider { get; set; } = default!;
 
-    protected ILoggerFactory LoggerFactory => LazyServiceProvider.LazyGetService<ILoggerFactory>();
+    protected ILoggerFactory? LoggerFactory => LazyServiceProvider.LazyGetService<ILoggerFactory>();
 
-    protected ILogger Logger => LazyServiceProvider.LazyGetService<ILogger>(provider => LoggerFactory?.CreateLogger(GetType().FullName) ?? NullLogger.Instance);
+    protected ILogger Logger => LazyServiceProvider.LazyGetService<ILogger>(provider => LoggerFactory?.CreateLogger(GetType().FullName!) ?? NullLogger.Instance);
 
-    protected ICurrentUser CurrentUser => LazyServiceProvider.LazyGetService<ICurrentUser>();
+    protected ICurrentUser CurrentUser => LazyServiceProvider.LazyGetService<ICurrentUser>()!;
 
-    protected ICurrentTenant CurrentTenant => LazyServiceProvider.LazyGetService<ICurrentTenant>();
+    protected ICurrentTenant CurrentTenant => LazyServiceProvider.LazyGetService<ICurrentTenant>()!;
 
-    protected IAuthorizationService AuthorizationService => LazyServiceProvider.LazyGetService<IAuthorizationService>();
+    protected IAuthorizationService AuthorizationService => LazyServiceProvider.LazyGetService<IAuthorizationService>()!;
 
-    protected IClock Clock => LazyServiceProvider.LazyGetService<IClock>();
+    protected IClock Clock => LazyServiceProvider.LazyGetService<IClock>()!;
 
-    protected IStringLocalizerFactory StringLocalizerFactory => LazyServiceProvider.LazyGetService<IStringLocalizerFactory>();
+    protected IStringLocalizerFactory StringLocalizerFactory => LazyServiceProvider.LazyGetService<IStringLocalizerFactory>()!;
 
     protected IStringLocalizer L {
         get {
@@ -43,16 +43,16 @@ public abstract class AbpHub : Hub
             return _localizer;
         }
     }
-    private IStringLocalizer _localizer;
+    private IStringLocalizer? _localizer;
 
-    protected Type LocalizationResource {
+    protected Type? LocalizationResource {
         get => _localizationResource;
         set {
             _localizationResource = value;
             _localizer = null;
         }
     }
-    private Type _localizationResource = typeof(DefaultResource);
+    private Type? _localizationResource = typeof(DefaultResource);
 
     protected virtual IStringLocalizer CreateLocalizer()
     {
@@ -74,23 +74,23 @@ public abstract class AbpHub : Hub
 public abstract class AbpHub<T> : Hub<T>
     where T : class
 {
-    public IAbpLazyServiceProvider LazyServiceProvider { get; set; }
+    public IAbpLazyServiceProvider LazyServiceProvider { get; set; } = default!;
 
-    public IServiceProvider ServiceProvider { get; set; }
+    public IServiceProvider ServiceProvider { get; set; } = default!;
 
-    protected ILoggerFactory LoggerFactory => LazyServiceProvider.LazyGetService<ILoggerFactory>();
+    protected ILoggerFactory? LoggerFactory => LazyServiceProvider.LazyGetService<ILoggerFactory>();
 
-    protected ILogger Logger => LazyServiceProvider.LazyGetService<ILogger>(provider => LoggerFactory?.CreateLogger(GetType().FullName) ?? NullLogger.Instance);
+    protected ILogger Logger => LazyServiceProvider.LazyGetService<ILogger>(provider => LoggerFactory?.CreateLogger(GetType().FullName!) ?? NullLogger.Instance);
 
-    protected ICurrentUser CurrentUser => LazyServiceProvider.LazyGetService<ICurrentUser>();
+    protected ICurrentUser CurrentUser => LazyServiceProvider.LazyGetService<ICurrentUser>()!;
 
-    protected ICurrentTenant CurrentTenant => LazyServiceProvider.LazyGetService<ICurrentTenant>();
+    protected ICurrentTenant CurrentTenant => LazyServiceProvider.LazyGetService<ICurrentTenant>()!;
 
-    protected IAuthorizationService AuthorizationService => LazyServiceProvider.LazyGetService<IAuthorizationService>();
+    protected IAuthorizationService AuthorizationService => LazyServiceProvider.LazyGetService<IAuthorizationService>()!;
 
-    protected IClock Clock => LazyServiceProvider.LazyGetService<IClock>();
+    protected IClock Clock => LazyServiceProvider.LazyGetService<IClock>()!;
 
-    protected IStringLocalizerFactory StringLocalizerFactory => LazyServiceProvider.LazyGetService<IStringLocalizerFactory>();
+    protected IStringLocalizerFactory StringLocalizerFactory => LazyServiceProvider.LazyGetService<IStringLocalizerFactory>()!;
 
     protected IStringLocalizer L {
         get {
@@ -102,16 +102,16 @@ public abstract class AbpHub<T> : Hub<T>
             return _localizer;
         }
     }
-    private IStringLocalizer _localizer;
+    private IStringLocalizer? _localizer;
 
-    protected Type LocalizationResource {
+    protected Type? LocalizationResource {
         get => _localizationResource;
         set {
             _localizationResource = value;
             _localizer = null;
         }
     }
-    private Type _localizationResource = typeof(DefaultResource);
+    private Type? _localizationResource = typeof(DefaultResource);
 
     protected virtual IStringLocalizer CreateLocalizer()
     {
diff --git a/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/AbpHubContext.cs b/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/AbpHubContext.cs
index 8c6b53950d..276ddb62d2 100644
--- a/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/AbpHubContext.cs
+++ b/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/AbpHubContext.cs
@@ -13,9 +13,9 @@ public class AbpHubContext
 
     public MethodInfo HubMethod { get; }
 
-    public IReadOnlyList<object> HubMethodArguments { get; }
+    public IReadOnlyList<object?> HubMethodArguments { get; }
 
-    public AbpHubContext(IServiceProvider serviceProvider, Hub hub, MethodInfo hubMethod, IReadOnlyList<object> hubMethodArguments)
+    public AbpHubContext(IServiceProvider serviceProvider, Hub hub, MethodInfo hubMethod, IReadOnlyList<object?> hubMethodArguments)
     {
         ServiceProvider = serviceProvider;
         Hub = hub;
diff --git a/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/AbpHubContextAccessorHubFilter.cs b/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/AbpHubContextAccessorHubFilter.cs
index d88a831685..da774bc13c 100644
--- a/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/AbpHubContextAccessorHubFilter.cs
+++ b/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/AbpHubContextAccessorHubFilter.cs
@@ -7,7 +7,7 @@ namespace Volo.Abp.AspNetCore.SignalR;
 
 public class AbpHubContextAccessorHubFilter : IHubFilter
 {
-    public virtual async ValueTask<object> InvokeMethodAsync(HubInvocationContext invocationContext, Func<HubInvocationContext, ValueTask<object>> next)
+    public virtual async ValueTask<object?> InvokeMethodAsync(HubInvocationContext invocationContext, Func<HubInvocationContext, ValueTask<object?>> next)
     {
         var hubContextAccessor = invocationContext.ServiceProvider.GetRequiredService<IAbpHubContextAccessor>();
         using (hubContextAccessor.Change(new AbpHubContext(
diff --git a/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/AbpSignalRUserIdProvider.cs b/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/AbpSignalRUserIdProvider.cs
index 99ce721375..896f51ab25 100644
--- a/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/AbpSignalRUserIdProvider.cs
+++ b/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/AbpSignalRUserIdProvider.cs
@@ -17,7 +17,7 @@ public class AbpSignalRUserIdProvider : IUserIdProvider, ITransientDependency
         _currentUser = currentUser;
     }
 
-    public virtual string GetUserId(HubConnectionContext connection)
+    public virtual string? GetUserId(HubConnectionContext connection)
     {
         using (_currentPrincipalAccessor.Change(connection.User))
         {
diff --git a/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/Auditing/AbpAuditHubFilter.cs b/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/Auditing/AbpAuditHubFilter.cs
index e76f415f18..7d3c21f067 100644
--- a/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/Auditing/AbpAuditHubFilter.cs
+++ b/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/Auditing/AbpAuditHubFilter.cs
@@ -14,7 +14,7 @@ namespace Volo.Abp.AspNetCore.SignalR.Auditing;
 
 public class AbpAuditHubFilter : IHubFilter
 {
-    public virtual async ValueTask<object> InvokeMethodAsync(HubInvocationContext invocationContext, Func<HubInvocationContext, ValueTask<object>> next)
+    public virtual async ValueTask<object?> InvokeMethodAsync(HubInvocationContext invocationContext, Func<HubInvocationContext, ValueTask<object?>> next)
     {
         var options = invocationContext.ServiceProvider.GetRequiredService<IOptions<AbpAuditingOptions>>().Value;
         if (!options.IsEnabled)
@@ -27,7 +27,7 @@ public class AbpAuditHubFilter : IHubFilter
         using (var saveHandle = auditingManager.BeginScope())
         {
             Debug.Assert(auditingManager.Current != null);
-            object result;
+            object? result;
             try
             {
                 result = await next(invocationContext);
diff --git a/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/Authentication/AbpAuthenticationHubFilter.cs b/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/Authentication/AbpAuthenticationHubFilter.cs
index 0a509e74ae..ab79521159 100644
--- a/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/Authentication/AbpAuthenticationHubFilter.cs
+++ b/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/Authentication/AbpAuthenticationHubFilter.cs
@@ -8,10 +8,10 @@ namespace Volo.Abp.AspNetCore.SignalR.Authentication;
 
 public class AbpAuthenticationHubFilter : IHubFilter
 {
-    public virtual async ValueTask<object> InvokeMethodAsync(HubInvocationContext invocationContext, Func<HubInvocationContext, ValueTask<object>> next)
+    public virtual async ValueTask<object?> InvokeMethodAsync(HubInvocationContext invocationContext, Func<HubInvocationContext, ValueTask<object?>> next)
     {
         var currentPrincipalAccessor = invocationContext.ServiceProvider.GetRequiredService<ICurrentPrincipalAccessor>();
-        using (currentPrincipalAccessor.Change(invocationContext.Context.User))
+        using (currentPrincipalAccessor.Change(invocationContext.Context.User!))
         {
             return await next(invocationContext);
         }
@@ -20,16 +20,16 @@ public class AbpAuthenticationHubFilter : IHubFilter
     public virtual async Task OnConnectedAsync(HubLifetimeContext context, Func<HubLifetimeContext, Task> next)
     {
         var currentPrincipalAccessor = context.ServiceProvider.GetRequiredService<ICurrentPrincipalAccessor>();
-        using (currentPrincipalAccessor.Change(context.Context.User))
+        using (currentPrincipalAccessor.Change(context.Context.User!))
         {
             await next(context);
         }
     }
 
-    public virtual async Task OnDisconnectedAsync(HubLifetimeContext context, Exception exception, Func<HubLifetimeContext, Exception, Task> next)
+    public virtual async Task OnDisconnectedAsync(HubLifetimeContext context, Exception? exception, Func<HubLifetimeContext, Exception?, Task> next)
     {
         var currentPrincipalAccessor = context.ServiceProvider.GetRequiredService<ICurrentPrincipalAccessor>();
-        using (currentPrincipalAccessor.Change(context.Context.User))
+        using (currentPrincipalAccessor.Change(context.Context.User!))
         {
             await next(context, exception);
         }
diff --git a/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/DefaultAbpHubContextAccessor.cs b/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/DefaultAbpHubContextAccessor.cs
index c1473b0569..76099d5feb 100644
--- a/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/DefaultAbpHubContextAccessor.cs
+++ b/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/DefaultAbpHubContextAccessor.cs
@@ -6,7 +6,7 @@ namespace Volo.Abp.AspNetCore.SignalR;
 
 public class DefaultAbpHubContextAccessor : IAbpHubContextAccessor, ISingletonDependency
 {
-    public AbpHubContext Context => _currentHubContext.Value;
+    public AbpHubContext Context => _currentHubContext.Value!;
 
     private readonly AsyncLocal<AbpHubContext> _currentHubContext = new AsyncLocal<AbpHubContext>();
 
diff --git a/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/HubConfig.cs b/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/HubConfig.cs
index 2263dcb7bc..514f6614b0 100644
--- a/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/HubConfig.cs
+++ b/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/HubConfig.cs
@@ -20,7 +20,7 @@ public class HubConfig
     public HubConfig(
         [NotNull] Type hubType,
         [NotNull] string routePattern,
-        [CanBeNull] Action<HttpConnectionDispatcherOptions> configureAction = null)
+        Action<HttpConnectionDispatcherOptions>? configureAction = null)
     {
         HubType = Check.NotNull(hubType, nameof(hubType));
         RoutePattern = Check.NotNullOrWhiteSpace(routePattern, nameof(routePattern));
diff --git a/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/HubConfigList.cs b/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/HubConfigList.cs
index fca0f2b5a4..158a97d8c4 100644
--- a/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/HubConfigList.cs
+++ b/framework/src/Volo.Abp.AspNetCore.SignalR/Volo/Abp/AspNetCore/SignalR/HubConfigList.cs
@@ -6,12 +6,12 @@ namespace Volo.Abp.AspNetCore.SignalR;
 
 public class HubConfigList : List<HubConfig>
 {
-    public void AddOrUpdate<THub>(Action<HubConfig> configAction = null)
+    public void AddOrUpdate<THub>(Action<HubConfig>? configAction = null)
     {
         AddOrUpdate(typeof(THub));
     }
 
-    public void AddOrUpdate(Type hubType, Action<HubConfig> configAction = null)
+    public void AddOrUpdate(Type hubType, Action<HubConfig>? configAction = null)
     {
         var hubConfig = this.GetOrAdd(
             c => c.HubType == hubType,
diff --git a/framework/src/Volo.Abp.AspNetCore.TestBase/Volo.Abp.AspNetCore.TestBase.csproj b/framework/src/Volo.Abp.AspNetCore.TestBase/Volo.Abp.AspNetCore.TestBase.csproj
index 07e3a08920..a6f6a55f39 100644
--- a/framework/src/Volo.Abp.AspNetCore.TestBase/Volo.Abp.AspNetCore.TestBase.csproj
+++ b/framework/src/Volo.Abp.AspNetCore.TestBase/Volo.Abp.AspNetCore.TestBase.csproj
@@ -5,6 +5,8 @@
 
   <PropertyGroup>
     <TargetFramework>net7.0</TargetFramework>
+    <Nullable>enable</Nullable>
+    <WarningsAsErrors>Nullable</WarningsAsErrors>
     <AssemblyName>Volo.Abp.AspNetCore.TestBase</AssemblyName>
     <PackageId>Volo.Abp.AspNetCore.TestBase</PackageId>
     <AssetTargetFallback>$(AssetTargetFallback);portable-net45+win8+wp8+wpa81;</AssetTargetFallback>
diff --git a/framework/src/Volo.Abp.AspNetCore.TestBase/Volo/Abp/AspNetCore/TestBase/AbpAspNetCoreAsyncIntegratedTestBase.cs b/framework/src/Volo.Abp.AspNetCore.TestBase/Volo/Abp/AspNetCore/TestBase/AbpAspNetCoreAsyncIntegratedTestBase.cs
index aa3ca0621f..8892623364 100644
--- a/framework/src/Volo.Abp.AspNetCore.TestBase/Volo/Abp/AspNetCore/TestBase/AbpAspNetCoreAsyncIntegratedTestBase.cs
+++ b/framework/src/Volo.Abp.AspNetCore.TestBase/Volo/Abp/AspNetCore/TestBase/AbpAspNetCoreAsyncIntegratedTestBase.cs
@@ -16,20 +16,20 @@ namespace Volo.Abp.AspNetCore.TestBase;
 public class AbpAspNetCoreAsyncIntegratedTestBase<TModule>
     where TModule : IAbpModule
 {
-    protected WebApplication WebApplication { get; set; }
+    protected WebApplication WebApplication { get; set; } = default!;
 
-    protected TestServer Server { get; set; }
+    protected TestServer Server { get; set; } = default!;
 
-    protected HttpClient Client { get; set; }
+    protected HttpClient Client { get; set; } = default!;
 
-    protected IServiceProvider ServiceProvider { get; set; }
+    protected IServiceProvider ServiceProvider { get; set; } = default!;
 
-    protected virtual T GetService<T>()
+    protected virtual T? GetService<T>()
     {
         return ServiceProvider.GetService<T>();
     }
 
-    protected virtual T GetRequiredService<T>()
+    protected virtual T GetRequiredService<T>() where T : notnull
     {
         return ServiceProvider.GetRequiredService<T>();
     }
diff --git a/framework/src/Volo.Abp.AspNetCore.TestBase/Volo/Abp/AspNetCore/TestBase/TestServerAccessor.cs b/framework/src/Volo.Abp.AspNetCore.TestBase/Volo/Abp/AspNetCore/TestBase/TestServerAccessor.cs
index dbf2db4495..d7e37f1575 100644
--- a/framework/src/Volo.Abp.AspNetCore.TestBase/Volo/Abp/AspNetCore/TestBase/TestServerAccessor.cs
+++ b/framework/src/Volo.Abp.AspNetCore.TestBase/Volo/Abp/AspNetCore/TestBase/TestServerAccessor.cs
@@ -5,5 +5,5 @@ namespace Volo.Abp.AspNetCore.TestBase;
 
 public class TestServerAccessor : ITestServerAccessor, ISingletonDependency
 {
-    public TestServer Server { get; set; }
+    public TestServer Server { get; set; } = default!;
 }