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diff --git a/.github/workflows/quick-test.yml b/.github/workflows/quick-test.yml
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+name: Quick Tests
+
+on:
+  pull_request:
+    paths-ignore:
+    - 'doc/**'
+
+jobs:
+  Linux:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        compiler: [g++-5, g++-8, clang-4.0, clang-9]
+    steps:
+      - uses: actions/checkout@v2
+      - name: install dependencies
+        run: |
+            export DEBIAN_FRONTEND=noninteractive
+            sudo apt-get install -y build-essential git zlib1g-dev cmake libssl-dev ${{ matrix.compiler }}
+      - name: super-test
+        run: |
+            ./super-test.sh quick ${{ matrix.compiler }}
+  MacOS:
+    runs-on: macos-latest
+    strategy:
+      fail-fast: false
+    steps:
+      - uses: actions/checkout@v2
+      - name: install dependencies
+        run: |
+            brew install autoconf automake libtool pkg-config
+      - name: super-test
+        run: |
+            ./super-test.sh quick
+  MSVC:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: ['windows-2016', 'windows-latest']
+        include:
+          - os: windows-2016
+            target: 'Visual Studio 15 2017'
+          - os: windows-latest
+            target: 'Visual Studio 16 2019'
+    steps:
+      - uses: actions/checkout@v2
+      - name: Build and test
+        shell: cmd
+        run: |
+            echo "Building Cap'n Proto with ${{ matrix.target }}"
+            cmake -Hc++ -Bbuild-output -G "${{ matrix.target }}" -DCMAKE_INSTALL_PREFIX=%CD%\capnproto-c++-install
+            cmake --build build-output --config debug --target install
+
+            echo "Building Cap'n Proto samples with ${{ matrix.target }}"
+            cmake -Hc++/samples -Bbuild-output-samples -G "${{ matrix.target }}" -DCMAKE_PREFIX_PATH=%CD%\capnproto-c++-install
+            cmake --build build-output-samples --config debug
+
+            cd build-output\src
+            ctest -V -C debug
+  MinGW:
+    runs-on: windows-latest
+    strategy:
+      fail-fast: false
+    steps:
+      - uses: actions/checkout@v2
+      - name: Build and test
+        shell: cmd
+        run: |
+            echo "Building Cap'n Proto with MinGW"
+            cmake -Hc++ -Bbuild-output -G "MinGW Makefiles" -DCMAKE_BUILD_TYPE=debug -DCMAKE_INSTALL_PREFIX=%CD%\capnproto-c++-install -DCMAKE_SH="CMAKE_SH-NOTFOUND"
+            cmake --build build-output --target install -- -j2
+
+            echo "Building Cap'n Proto samples with MinGW"
+            cmake -Hc++/samples -Bbuild-output-samples -G "MinGW Makefiles" -DCMAKE_BUILD_TYPE=debug -DCMAKE_PREFIX_PATH=%CD%\capnproto-c++-install -DCMAKE_SH="CMAKE_SH-NOTFOUND"
+            cmake --build build-output-samples
+
+            cd build-output\src
+            ctest -V -C debug
+  Cygwin:
+    runs-on: windows-latest
+    strategy:
+      fail-fast: false
+    steps:
+      - run: git config --global core.autocrlf false
+      - uses: actions/checkout@v2
+      # TODO(someday): If we could cache the Cygwin installation we wouldn't have to spend three
+      #     minutes installing it for every build. Unfortuntaley, actions/cache@v1 does not preserve
+      #     DOS file attributes, which corrupts the Cygwin install. In particular, Cygwin marks
+      #     symlinks with the "DOS SYSTEM" attribute. We could cache just the downloaded packages,
+      #     but it turns out that only saves a couple seconds; most of the time is spend unpacking.
+      - name: Install Cygwin
+        run: |
+          choco config get cacheLocation
+          choco install --no-progress cygwin
+      - name: Install Cygwin additional packages
+        shell: cmd
+        run: |
+          C:\tools\cygwin\cygwinsetup.exe -qgnNdO -R C:/tools/cygwin -l C:/tools/cygwin/packages -s http://mirrors.kernel.org/sourceware/cygwin/ -P autoconf,automake,libtool,gcc,gcc-g++,binutils,libssl-devel,make,zlib-devel,pkg-config,cmake,xxd
+      - name: Build and test
+        shell: cmd
+        run: |
+          C:\tools\cygwin\bin\bash -lc 'export PATH=/usr/local/bin:/usr/bin:/bin; cd /cygdrive/d/a/capnproto/capnproto; ./super-test.sh quick'