diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index e12536d2..b3338755 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -16,10 +16,10 @@ jobs:
 
     steps:
       - uses: actions/checkout@v4
-      - name: Setup .NET SDK 8.0.x
+      - name: Setup .NET SDK 9.0.x
         uses: actions/setup-dotnet@v3
         with:
-          dotnet-version: 8.0.x
+          dotnet-version: 9.0.x
 
       - name: Show dotnet Version
         run: |
diff --git a/.github/workflows/buildandtest.yml b/.github/workflows/buildandtest.yml
index d6cdeadc..a7f79bf5 100644
--- a/.github/workflows/buildandtest.yml
+++ b/.github/workflows/buildandtest.yml
@@ -38,10 +38,10 @@ jobs:
 
     steps:
       - uses: actions/checkout@v4
-      - name: Setup .NET SDK 8.0.x
+      - name: Setup .NET SDK 9.0.x
         uses: actions/setup-dotnet@v3
         with:
-          dotnet-version: 8.0.x
+          dotnet-version: 9.0.x
 
       - name: Show dotnet Version
         run: |
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 69fb722b..aba877fd 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -17,7 +17,7 @@ jobs:
       - name: Setup .NET Core
         uses: actions/setup-dotnet@v3
         with:
-          dotnet-version: 8.0.x
+          dotnet-version: 9.0.x
       - name: Build with dotnet
         run: dotnet build --configuration Release /home/runner/work/EasyCaching/EasyCaching/EasyCaching.sln
       - name: Pack with dotnet
diff --git a/.github/workflows/release_stable.yml b/.github/workflows/release_stable.yml
index d6aedfff..b15f938e 100644
--- a/.github/workflows/release_stable.yml
+++ b/.github/workflows/release_stable.yml
@@ -15,7 +15,7 @@ jobs:
       - name: Setup .NET Core
         uses: actions/setup-dotnet@v3
         with:
-          dotnet-version: 8.0.x
+          dotnet-version: 9.0.x
       - name: Build with dotnet
         run: dotnet build --configuration Release /home/runner/work/EasyCaching/EasyCaching/EasyCaching.sln
       - name: Pack with dotnet
diff --git a/bus/EasyCaching.Bus.Zookeeper/DefaultZookeeperBus.cs b/bus/EasyCaching.Bus.Zookeeper/DefaultZookeeperBus.cs
index e314bf79..1ed0734b 100644
--- a/bus/EasyCaching.Bus.Zookeeper/DefaultZookeeperBus.cs
+++ b/bus/EasyCaching.Bus.Zookeeper/DefaultZookeeperBus.cs
@@ -1,18 +1,18 @@
-namespace EasyCaching.Bus.Zookeeper
+using EasyCaching.Core;
+using EasyCaching.Core.Bus;
+using EasyCaching.Core.Serialization;
+using Microsoft.Extensions.Options;
+using org.apache.zookeeper;
+using org.apache.zookeeper.data;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace EasyCaching.Bus.Zookeeper
 {
-    using EasyCaching.Core;
-    using EasyCaching.Core.Bus;
-    using EasyCaching.Core.Serialization;
-    using Microsoft.Extensions.Options;
-    using org.apache.zookeeper;
-    using org.apache.zookeeper.data;
-    using System;
-    using System.Collections.Generic;
-    using System.Linq;
-    using System.Text;
-    using System.Threading;
-    using System.Threading.Tasks;
-
     public class DefaultZookeeperBus : EasyCachingAbstractBus
     {
         /// <summary>
@@ -41,7 +41,7 @@ public class DefaultZookeeperBus : EasyCachingAbstractBus
         /// <summary>
         /// lock
         /// </summary>
-        private readonly object _zkEventLock = new object();
+        private readonly Lock _zkEventLock = LockFactory.Create();
 
         /// <summary>
         /// The serializer.
@@ -214,7 +214,7 @@ private async Task SubscribeDataChange(WatchedEvent @event)
         /// <returns></returns>
         private async Task ReZkConnect()
         {
-            if (!Monitor.TryEnter(_zkEventLock, _zkBusOptions.ConnectionTimeout))
+            if (!_zkEventLock.TryEnter(_zkBusOptions.ConnectionTimeout))
                 return;
             try
             {
@@ -234,7 +234,7 @@ private async Task ReZkConnect()
             }
             finally
             {
-                Monitor.Exit(_zkEventLock);
+                _zkEventLock.Exit();
             }
         }
 
diff --git a/bus/EasyCaching.Bus.Zookeeper/EasyCaching.Bus.Zookeeper.csproj b/bus/EasyCaching.Bus.Zookeeper/EasyCaching.Bus.Zookeeper.csproj
index 23c4c22d..c1cb329c 100644
--- a/bus/EasyCaching.Bus.Zookeeper/EasyCaching.Bus.Zookeeper.csproj
+++ b/bus/EasyCaching.Bus.Zookeeper/EasyCaching.Bus.Zookeeper.csproj
@@ -3,7 +3,8 @@
 	<Import Project="../../build/version.props" />
 	<Import Project="../../build/releasenotes.props" />
 	<PropertyGroup>
-		<TargetFrameworks>netstandard2.0;net8.0</TargetFrameworks>
+		<TargetFrameworks>netstandard2.0;net8.0;net9.0</TargetFrameworks>
+		<LangVersion>latest</LangVersion>
 		<Owners>ncc;Catcher Wong</Owners>
 		<Authors>ncc;Catcher Wong</Authors>
 		<VersionPrefix>$(EasyCachingZookeeperBusPackageVersion)</VersionPrefix>
@@ -40,4 +41,11 @@
 	  <PackageReference Include="ZooKeeperNetEx" Version="3.4.12.4" />
 	</ItemGroup>
 
+	<ItemGroup>
+	  <PackageReference Include="Backport.System.Threading.Lock" Version="2.0.7" />
+	  <Using Condition="$([MSBuild]::IsTargetFrameworkCompatible('$(TargetFramework)', 'net9.0'))" Alias="Lock" Include="System.Threading.Lock" />
+	  <Using Condition="!$([MSBuild]::IsTargetFrameworkCompatible('$(TargetFramework)', 'net9.0'))" Alias="Lock" Include="Backport.System.Threading.Lock" />
+	  <Using Alias="LockFactory" Include="Backport.System.Threading.LockFactory" />
+	</ItemGroup>
+
 </Project>
diff --git a/sample/EasyCaching.Demo.ConsoleApp/EasyCaching.Demo.ConsoleApp.csproj b/sample/EasyCaching.Demo.ConsoleApp/EasyCaching.Demo.ConsoleApp.csproj
index 1d45c7c8..d5d5a26d 100644
--- a/sample/EasyCaching.Demo.ConsoleApp/EasyCaching.Demo.ConsoleApp.csproj
+++ b/sample/EasyCaching.Demo.ConsoleApp/EasyCaching.Demo.ConsoleApp.csproj
@@ -2,7 +2,7 @@
 
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net8.0</TargetFramework>
+    <TargetFramework>net9.0</TargetFramework>
     <IsPackable>false</IsPackable>
   </PropertyGroup>
 
diff --git a/sample/EasyCaching.Demo.Interceptors/EasyCaching.Demo.Interceptors.csproj b/sample/EasyCaching.Demo.Interceptors/EasyCaching.Demo.Interceptors.csproj
index fdf6b5fb..3706621a 100644
--- a/sample/EasyCaching.Demo.Interceptors/EasyCaching.Demo.Interceptors.csproj
+++ b/sample/EasyCaching.Demo.Interceptors/EasyCaching.Demo.Interceptors.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk.Web">
 
   <PropertyGroup>
-	  <TargetFramework>net8.0</TargetFramework>
+	  <TargetFramework>net9.0</TargetFramework>
   </PropertyGroup>
 
   <ItemGroup>
diff --git a/sample/EasyCaching.Demo.Locks/EasyCaching.Demo.Locks.csproj b/sample/EasyCaching.Demo.Locks/EasyCaching.Demo.Locks.csproj
index 0e6245ee..624823a1 100644
--- a/sample/EasyCaching.Demo.Locks/EasyCaching.Demo.Locks.csproj
+++ b/sample/EasyCaching.Demo.Locks/EasyCaching.Demo.Locks.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk.Web">
 
   <PropertyGroup>
-    <TargetFramework>net8.0</TargetFramework>
+    <TargetFramework>net9.0</TargetFramework>
     <Nullable>enable</Nullable>
     <ImplicitUsings>enable</ImplicitUsings>
   </PropertyGroup>
diff --git a/sample/EasyCaching.Demo.Providers/EasyCaching.Demo.Providers.csproj b/sample/EasyCaching.Demo.Providers/EasyCaching.Demo.Providers.csproj
index aac47298..74bb9dfc 100644
--- a/sample/EasyCaching.Demo.Providers/EasyCaching.Demo.Providers.csproj
+++ b/sample/EasyCaching.Demo.Providers/EasyCaching.Demo.Providers.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk.Web">
 
   <PropertyGroup>
-	  <TargetFramework>net8.0</TargetFramework>
+	  <TargetFramework>net9.0</TargetFramework>
   </PropertyGroup>
 
   <ItemGroup>
diff --git a/sample/EasyCaching.Demo.ResponseCaching/EasyCaching.Demo.ResponseCaching.csproj b/sample/EasyCaching.Demo.ResponseCaching/EasyCaching.Demo.ResponseCaching.csproj
index 03f9b2c7..d12a87a2 100644
--- a/sample/EasyCaching.Demo.ResponseCaching/EasyCaching.Demo.ResponseCaching.csproj
+++ b/sample/EasyCaching.Demo.ResponseCaching/EasyCaching.Demo.ResponseCaching.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk.Web">
 
   <PropertyGroup>
-	  <TargetFramework>net8.0</TargetFramework>
+	  <TargetFramework>net9.0</TargetFramework>
   </PropertyGroup>
 
 
diff --git a/src/EasyCaching.Core/DistributedLock/DistributedLock.cs b/src/EasyCaching.Core/DistributedLock/DistributedLock.cs
index 4ae267c0..9003cf33 100644
--- a/src/EasyCaching.Core/DistributedLock/DistributedLock.cs
+++ b/src/EasyCaching.Core/DistributedLock/DistributedLock.cs
@@ -9,7 +9,7 @@ namespace EasyCaching.Core.DistributedLock
     public class DistributedLock : MemoryLock
     {
         private readonly IDistributedLockProvider _provider;
-        private readonly object _syncObj = new object();
+        private readonly Lock _syncObj = LockFactory.Create();
         private readonly DistributedLockOptions _options;
         private readonly ILogger _logger;
 
diff --git a/src/EasyCaching.Core/DistributedLock/MemoryLock.cs b/src/EasyCaching.Core/DistributedLock/MemoryLock.cs
index c1d01f57..5facbcfd 100644
--- a/src/EasyCaching.Core/DistributedLock/MemoryLock.cs
+++ b/src/EasyCaching.Core/DistributedLock/MemoryLock.cs
@@ -16,7 +16,7 @@ public class MemoryLock : IDistributedLock
 
         public string Key { get; }
 
-        private readonly object _syncObj = new object();
+        private readonly Lock _syncObj = LockFactory.Create();
 
         public MemoryLock(string key) => Key = key;
 
diff --git a/src/EasyCaching.Core/EasyCaching.Core.csproj b/src/EasyCaching.Core/EasyCaching.Core.csproj
index 1a373291..81a35085 100644
--- a/src/EasyCaching.Core/EasyCaching.Core.csproj
+++ b/src/EasyCaching.Core/EasyCaching.Core.csproj
@@ -2,7 +2,8 @@
 	<Import Project="../../build/version.props" />
 	<Import Project="../../build/releasenotes.props" />
 	<PropertyGroup>
-		<TargetFrameworks>netstandard2.0;net8.0</TargetFrameworks>
+		<TargetFrameworks>netstandard2.0;net8.0;net9.0</TargetFrameworks>
+		<LangVersion>latest</LangVersion>
 		<Owners>ncc;Catcher Wong</Owners>
 		<Authors>ncc;Catcher Wong</Authors>
 		<VersionPrefix>$(EasyCachingCorePackageVersion)</VersionPrefix>
@@ -44,8 +45,21 @@
 		<PackageReference Include="Microsoft.Extensions.Logging" Version="8.0.1" />
 	</ItemGroup>
 
+	<ItemGroup Condition="'$(TargetFramework)' == 'net9.0'">
+		<PackageReference Include="Microsoft.Extensions.Options.ConfigurationExtensions" Version="9.0.0" />
+		<PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="9.0.0" />
+		<PackageReference Include="Microsoft.Extensions.Logging" Version="9.0.0" />
+	</ItemGroup>
+
 	<ItemGroup>
 	  <PackageReference Include="AsyncKeyedLock" Version="7.0.1" />
 	</ItemGroup>
+	
+	<ItemGroup>
+	  <PackageReference Include="Backport.System.Threading.Lock" Version="2.0.7" />
+	  <Using Condition="$([MSBuild]::IsTargetFrameworkCompatible('$(TargetFramework)', 'net9.0'))" Alias="Lock" Include="System.Threading.Lock" />
+	  <Using Condition="!$([MSBuild]::IsTargetFrameworkCompatible('$(TargetFramework)', 'net9.0'))" Alias="Lock" Include="Backport.System.Threading.Lock" />
+	  <Using Alias="LockFactory" Include="Backport.System.Threading.LockFactory" />
+	</ItemGroup>	
 
 </Project>
diff --git a/test/EasyCaching.UnitTests/CachingTests/CSRedisCachingProviderTest.cs b/test/EasyCaching.UnitTests/CachingTests/CSRedisCachingProviderTest.cs
index 8ded8e1a..c0e16ac2 100644
--- a/test/EasyCaching.UnitTests/CachingTests/CSRedisCachingProviderTest.cs
+++ b/test/EasyCaching.UnitTests/CachingTests/CSRedisCachingProviderTest.cs
@@ -42,7 +42,7 @@ protected override IEasyCachingProvider CreateCachingProvider(Action<BaseProvide
         }
 
         /*[Fact]
-        public async void Use_Redis6_ACL_Should_Succeed()
+        public async Task Use_Redis6_ACL_Should_Succeed()
         {
             IServiceCollection services = new ServiceCollection();
             services.AddEasyCaching(x =>
diff --git a/test/EasyCaching.UnitTests/CachingTests/MemcachedProviderTest.cs b/test/EasyCaching.UnitTests/CachingTests/MemcachedProviderTest.cs
index 0d5cf30a..c1275375 100644
--- a/test/EasyCaching.UnitTests/CachingTests/MemcachedProviderTest.cs
+++ b/test/EasyCaching.UnitTests/CachingTests/MemcachedProviderTest.cs
@@ -417,7 +417,7 @@ public void Provider_Information_Should_Be_Correct()
     public class MemcachedProviderNoConnectionTest 
     {
         [Fact]
-        public async void NoConnectionTest()
+        public async Task NoConnectionTest()
         {
             IServiceCollection services = new ServiceCollection();
             services.AddLogging();
diff --git a/test/EasyCaching.UnitTests/CachingTests/MemoryCachingProviderTest.cs b/test/EasyCaching.UnitTests/CachingTests/MemoryCachingProviderTest.cs
index 511e5f2d..e32e0071 100644
--- a/test/EasyCaching.UnitTests/CachingTests/MemoryCachingProviderTest.cs
+++ b/test/EasyCaching.UnitTests/CachingTests/MemoryCachingProviderTest.cs
@@ -156,7 +156,7 @@ public void Evicted_Event_Should_Trigger_When_GetExpiredItems()
         }
 
         [Fact]
-        public async void Issues497_GetCountAsync_Check_Expires_Test()
+        public async Task Issues497_GetCountAsync_Check_Expires_Test()
         {
             for (int i = 0; i < 9; i++)
             {