diff --git a/Directory.Packages.props b/Directory.Packages.props
index e8a12f6..ecefaed 100644
--- a/Directory.Packages.props
+++ b/Directory.Packages.props
@@ -10,6 +10,7 @@
     <PackageVersion Include="Microsoft.Testing.Extensions.CodeCoverage" Version="18.3.1" />
     <PackageVersion Include="MSTest.TestAdapter" Version="4.0.2" />
     <PackageVersion Include="MSTest.TestFramework" Version="4.0.2" />
+    <PackageVersion Include="Polyfill" Version="9.7.0" />
     <PackageVersion Include="System.Memory" Version="4.6.3" />
   </ItemGroup>
 </Project>
diff --git a/SingleAppInstance/SingleAppInstance.csproj b/SingleAppInstance/SingleAppInstance.csproj
index 58e9527..05794a9 100644
--- a/SingleAppInstance/SingleAppInstance.csproj
+++ b/SingleAppInstance/SingleAppInstance.csproj
@@ -9,5 +9,6 @@
   <ItemGroup>
     <PackageReference Include="ktsu.AppDataStorage" />
     <PackageReference Include="ktsu.Semantics.Paths" />
+  <PackageReference Include="Polyfill" />
   </ItemGroup>
 </Project>