diff --git a/LazyCache.Ninject.UnitTests/LazyCache.Ninject.UnitTests.csproj b/LazyCache.Ninject.UnitTests/LazyCache.Ninject.UnitTests.csproj
index 7523aa1..6426959 100644
--- a/LazyCache.Ninject.UnitTests/LazyCache.Ninject.UnitTests.csproj
+++ b/LazyCache.Ninject.UnitTests/LazyCache.Ninject.UnitTests.csproj
@@ -7,9 +7,9 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="nunit" Version="3.11.0" />
+    <PackageReference Include="nunit" Version="3.12.0" />
     <PackageReference Include="NUnit3TestAdapter" Version="3.15.1" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="15.9.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.4.0" />
   </ItemGroup>
 
   <ItemGroup>
diff --git a/LazyCache.UnitTests/LazyCache.UnitTests.csproj b/LazyCache.UnitTests/LazyCache.UnitTests.csproj
index 965f86b..4c0d208 100644
--- a/LazyCache.UnitTests/LazyCache.UnitTests.csproj
+++ b/LazyCache.UnitTests/LazyCache.UnitTests.csproj
@@ -7,10 +7,10 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="fluentassertions" Version="5.6.0" />
-    <PackageReference Include="nunit" Version="3.11.0" />
+    <PackageReference Include="fluentassertions" Version="5.9.0" />
+    <PackageReference Include="nunit" Version="3.12.0" />
     <PackageReference Include="NUnit3TestAdapter" Version="3.15.1" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="15.9.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.4.0" />
   </ItemGroup>
 
   <ItemGroup>
diff --git a/LazyCache.UnitTestsCore21/LazyCache.UnitTestsCore21.csproj b/LazyCache.UnitTestsCore21/LazyCache.UnitTestsCore21.csproj
index 7ac83a9..5605db2 100644
--- a/LazyCache.UnitTestsCore21/LazyCache.UnitTestsCore21.csproj
+++ b/LazyCache.UnitTestsCore21/LazyCache.UnitTestsCore21.csproj
@@ -6,9 +6,9 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="nunit" Version="3.11.0" />
+    <PackageReference Include="nunit" Version="3.12.0" />
     <PackageReference Include="NUnit3TestAdapter" Version="3.15.1" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="15.9.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.4.0" />
   </ItemGroup>
 
   <ItemGroup>
diff --git a/LazyCache.UnitTestsCore22/LazyCache.UnitTestsCore22.csproj b/LazyCache.UnitTestsCore22/LazyCache.UnitTestsCore22.csproj
index 0552460..3903a11 100644
--- a/LazyCache.UnitTestsCore22/LazyCache.UnitTestsCore22.csproj
+++ b/LazyCache.UnitTestsCore22/LazyCache.UnitTestsCore22.csproj
@@ -6,9 +6,9 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="nunit" Version="3.11.0" />
+    <PackageReference Include="nunit" Version="3.12.0" />
     <PackageReference Include="NUnit3TestAdapter" Version="3.15.1" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="15.9.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.4.0" />
   </ItemGroup>
 
   <ItemGroup>
diff --git a/LazyCache.UnitTestsCore30/LazyCache.UnitTestsCore30.csproj b/LazyCache.UnitTestsCore30/LazyCache.UnitTestsCore30.csproj
index 0ba2658..4b239ec 100644
--- a/LazyCache.UnitTestsCore30/LazyCache.UnitTestsCore30.csproj
+++ b/LazyCache.UnitTestsCore30/LazyCache.UnitTestsCore30.csproj
@@ -6,9 +6,9 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="nunit" Version="3.11.0" />
+    <PackageReference Include="nunit" Version="3.12.0" />
     <PackageReference Include="NUnit3TestAdapter" Version="3.15.1" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="15.9.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.4.0" />
   </ItemGroup>
 
   <ItemGroup>
diff --git a/LazyCache.UnitTestsCore31/LazyCache.UnitTestsCore31.csproj b/LazyCache.UnitTestsCore31/LazyCache.UnitTestsCore31.csproj
index c5abb8c..f14df3a 100644
--- a/LazyCache.UnitTestsCore31/LazyCache.UnitTestsCore31.csproj
+++ b/LazyCache.UnitTestsCore31/LazyCache.UnitTestsCore31.csproj
@@ -6,9 +6,9 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="nunit" Version="3.11.0" />
+    <PackageReference Include="nunit" Version="3.12.0" />
     <PackageReference Include="NUnit3TestAdapter" Version="3.15.1" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="15.9.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.4.0" />
   </ItemGroup>
 
   <ItemGroup>
diff --git a/appveyor.yml b/appveyor.yml
index d915446..5c13be0 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -1,5 +1,5 @@
 version: '2.0.0.{build}'
-image: Visual Studio 2017
+image: Visual Studio 2019
 configuration: Release
 environment:
   LazyCacheVersion: 2.0.0