diff --git a/Capnp.Net.Runtime.Tests.Core21/Capnp.Net.Runtime.Tests.Core21.csproj b/Capnp.Net.Runtime.Tests.Core21/Capnp.Net.Runtime.Tests.Core21.csproj
index bc841b7..1541a85 100644
--- a/Capnp.Net.Runtime.Tests.Core21/Capnp.Net.Runtime.Tests.Core21.csproj
+++ b/Capnp.Net.Runtime.Tests.Core21/Capnp.Net.Runtime.Tests.Core21.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>netcoreapp2.2</TargetFramework>
+    <TargetFramework>netcoreapp2.1</TargetFramework>
 
     <IsPackable>false</IsPackable>
 
diff --git a/CapnpC.CSharp.Generator.Tests/CapnpC.CSharp.Generator.Tests.csproj b/CapnpC.CSharp.Generator.Tests/CapnpC.CSharp.Generator.Tests.csproj
index 410f90a..3ad4483 100644
--- a/CapnpC.CSharp.Generator.Tests/CapnpC.CSharp.Generator.Tests.csproj
+++ b/CapnpC.CSharp.Generator.Tests/CapnpC.CSharp.Generator.Tests.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>netcoreapp2.2</TargetFramework>
+    <TargetFramework>netcoreapp2.1</TargetFramework>
     <RootNamespace>CapnpC.CSharp.Generator.Tests</RootNamespace>
 
     <IsPackable>false</IsPackable>
diff --git a/CapnpC.CSharp.MsBuild.Generation.Tests/CapnpC.CSharp.MsBuild.Generation.Tests.csproj b/CapnpC.CSharp.MsBuild.Generation.Tests/CapnpC.CSharp.MsBuild.Generation.Tests.csproj
index 4b48f59..8fc6607 100644
--- a/CapnpC.CSharp.MsBuild.Generation.Tests/CapnpC.CSharp.MsBuild.Generation.Tests.csproj
+++ b/CapnpC.CSharp.MsBuild.Generation.Tests/CapnpC.CSharp.MsBuild.Generation.Tests.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>netcoreapp2.2</TargetFramework>
+    <TargetFramework>netcoreapp2.1</TargetFramework>
 
     <IsPackable>false</IsPackable>
 
diff --git a/appveyor.yml b/appveyor.yml
index 7d8f6c5..b18d96d 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -56,13 +56,13 @@ artifacts:
    type: NuGetPackage
 clone_depth: 1
 test_script:
-  - cmd: vstest.console /logger:Appveyor /inIsolation CapnpC.CSharp.Generator.Tests\bin\Release\netcoreapp2.2\CapnpC.CSharp.Generator.Tests.dll
+  - cmd: vstest.console /logger:Appveyor /inIsolation CapnpC.CSharp.Generator.Tests\bin\Release\netcoreapp2.1\CapnpC.CSharp.Generator.Tests.dll
   - cmd: cd %APPVEYOR_BUILD_FOLDER%\chocolatey\install
   - cmd: choco install capnpc-csharp --source=".;https://chocolatey.org/api/v2" --force -y
   - cmd: cd %APPVEYOR_BUILD_FOLDER%\install-test
   - cmd: compile-test
   - cmd: cd %APPVEYOR_BUILD_FOLDER%
-  - cmd: vstest.console /logger:Appveyor /inIsolation CapnpC.CSharp.Generator.Tests\bin\Release\netcoreapp2.2\CapnpC.CSharp.Generator.Tests.dll
+  - cmd: vstest.console /logger:Appveyor /inIsolation CapnpC.CSharp.Generator.Tests\bin\Release\netcoreapp2.1\CapnpC.CSharp.Generator.Tests.dll
   - cmd: choco uninstall capnpc-csharp -y
   - cmd: cd %APPVEYOR_BUILD_FOLDER%\install-test
   - cmd: notinstalled-test
@@ -73,13 +73,13 @@ test_script:
   - cmd: choco uninstall capnpc-csharp-win-x86 -y
   - cmd: notinstalled-test
   - cmd: cd %APPVEYOR_BUILD_FOLDER%
-  - cmd: vstest.console /logger:Appveyor /inIsolation CapnpC.CSharp.MsBuild.Generation.Tests\bin\Release\netcoreapp2.2\CapnpC.CSharp.MsBuild.Generation.Tests.dll
+  - cmd: vstest.console /logger:Appveyor /inIsolation CapnpC.CSharp.MsBuild.Generation.Tests\bin\Release\netcoreapp2.1\CapnpC.CSharp.MsBuild.Generation.Tests.dll
   - cmd: msbuild -t:restore ./MsBuildGenerationTest/MsBuildGenerationTest.csproj /p:Configuration="Debug" /p:PackageReferenceVersion="%APPVEYOR_BUILD_VERSION%"
   - cmd: msbuild ./MsBuildGenerationTest/MsBuildGenerationTest.sln /p:Configuration="Debug" /p:PackageReferenceVersion="%APPVEYOR_BUILD_VERSION%"
   - cmd: vstest.console /logger:Appveyor /inIsolation Capnp.Net.Runtime.Tests\bin\Debug\net471\Capnp.Net.Runtime.Tests.Std20.dll
   - cmd: vstest.console /logger:Appveyor /inIsolation Capnp.Net.Runtime.Tests\bin\Release\net471\Capnp.Net.Runtime.Tests.Std20.dll
-  - cmd: vstest.console /logger:Appveyor /inIsolation Capnp.Net.Runtime.Tests.Core21\bin\Debug\netcoreapp2.2\Capnp.Net.Runtime.Tests.Core21.dll
-  - cmd: vstest.console /logger:Appveyor /inIsolation Capnp.Net.Runtime.Tests.Core21\bin\Release\netcoreapp2.2\Capnp.Net.Runtime.Tests.Core21.dll
+  - cmd: vstest.console /logger:Appveyor /inIsolation Capnp.Net.Runtime.Tests.Core21\bin\Debug\netcoreapp2.1\Capnp.Net.Runtime.Tests.Core21.dll
+  - cmd: vstest.console /logger:Appveyor /inIsolation Capnp.Net.Runtime.Tests.Core21\bin\Release\netcoreapp2.1\Capnp.Net.Runtime.Tests.Core21.dll
 on_finish :
   # any cleanup in here
 deploy: