diff --git a/appveyor.yml b/appveyor.yml
index d002c39..2532470 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -15,6 +15,9 @@ before_build:
   - cmd: dotnet --version
   - cmd: msbuild -ver
   - cmd: dotnet restore ./Capnp.Net.Runtime/Capnp.Net.Runtime.csproj --verbosity m
+  - cmd: dotnet restore ./Capnp.Net.Runtime.Core21/Capnp.Net.Runtime.Core21.csproj --verbosity m
+  - cmd: dotnet restore ./Capnp.Net.Runtime.Tests/Capnp.Net.Runtime.Tests.Std20.csproj --verbosity m
+  - cmd: dotnet restore ./Capnp.Net.Runtime.Tests.Core21/Capnp.Net.Runtime.Tests.Core21.csproj --verbosity m
   - cmd: dotnet restore ./capnpc-csharp/capnpc-csharp.csproj --verbosity m  
 build_script:
   - cmd: msbuild ./Capnp.Net.sln /p:Configuration="Debug"