diff --git a/.ci/Dockerfile.2016 b/.ci/Dockerfile.2016
new file mode 100644
index 0000000..388d824
--- /dev/null
+++ b/.ci/Dockerfile.2016
@@ -0,0 +1,13 @@
+FROM mcr.microsoft.com/windows/servercore:ltsc2016
+
+COPY ./msys2-base-x86_64-latest.sfx.exe /msys2.exe
+
+RUN powershell -Command \
+  $ErrorActionPreference = 'Stop'; \
+  $ProgressPreference = 'SilentlyContinue'; \
+  /msys2.exe -y -oC:\; \
+  function msys() { C:\msys64\usr\bin\bash.exe @('-lc') + @Args; } \
+  msys ' '; \
+  msys 'pacman --noconfirm -Syuu'; \
+  msys 'pacman --noconfirm -Syuu'; \
+  msys 'pacman --noconfirm -Scc';
diff --git a/Dockerfile b/.ci/Dockerfile.2019
similarity index 51%
rename from Dockerfile
rename to .ci/Dockerfile.2019
index 2ee85e8..3e986ce 100644
--- a/Dockerfile
+++ b/.ci/Dockerfile.2019
@@ -1,12 +1,11 @@
 FROM mcr.microsoft.com/windows/servercore:ltsc2019
 
+COPY ./msys2-base-x86_64-latest.sfx.exe /msys2.exe
+
 RUN powershell -Command \
   $ErrorActionPreference = 'Stop'; \
   $ProgressPreference = 'SilentlyContinue'; \
-  [Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12; \
-  Invoke-WebRequest -UseBasicParsing -uri "https://github.com/msys2/msys2-installer/releases/download/nightly-x86_64/msys2-base-x86_64-latest.sfx.exe" -OutFile msys2.exe; \
-  .\msys2.exe -y -oC:\; \
-  Remove-Item msys2.exe ; \
+  /msys2.exe -y -oC:\; \
   function msys() { C:\msys64\usr\bin\bash.exe @('-lc') + @Args; } \
   msys ' '; \
   msys 'pacman --noconfirm -Syuu'; \
diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 1c3f62f..20722f9 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -42,16 +42,119 @@ jobs:
           sha256sum.exe msys2-*
           sha256sum.exe msys2-* > msys2-checksums.txt
 
+      - name: Create 'latest' Variants
+        run: |
+          cp msys2-base-x86_64-[0-9]*.sfx.exe msys2-base-x86_64-latest.sfx.exe
+          cp msys2-x86_64-[0-9]*.exe msys2-x86_64-latest.exe
+          cp msys2-*.tar.xz msys2-base-x86_64-latest.tar.xz
+
       - name: Upload Results
         uses: actions/upload-artifact@v2
         with:
           name: installer
           path: msys2-*
 
+  test-installer-2019:
+    needs: build-installer
+    runs-on: windows-2019
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+
+      - uses: actions/download-artifact@v2
+        with:
+          name: installer
+
+      - name: Install
+        run: |
+          ./msys2-x86_64-latest.exe in --confirm-command --accept-messages --root C:/msys2-install-test
+
+      - name: Test
+        run: |
+          C:\msys2-install-test\usr\bin\bash.exe -lc "pacman --version"
+          C:\msys2-install-test\usr\bin\bash.exe -lc "pacman -Qkv"
+          C:\msys2-install-test\usr\bin\bash.exe -lc "pacman -Syy"
+
+      - name: Uninstall
+        run: |
+          C:\msys2-install-test\uninstall.exe pr --confirm-command
+
+  test-installer-2016:
+    needs: build-installer
+    runs-on: windows-2016
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+
+      - uses: actions/download-artifact@v2
+        with:
+          name: installer
+
+      - name: Install
+        run: |
+          ./msys2-x86_64-latest.exe in --confirm-command --accept-messages --root C:/msys2-install-test
+
+      - name: Test
+        run: |
+          C:\msys2-install-test\usr\bin\bash.exe -lc "pacman --version"
+          C:\msys2-install-test\usr\bin\bash.exe -lc "pacman -Qkv"
+          C:\msys2-install-test\usr\bin\bash.exe -lc "pacman -Syy"
+
+      - name: Uninstall
+        run: |
+          C:\msys2-install-test\uninstall.exe pr --confirm-command
+
+  test-docker-sfx-2019:
+    needs: build-installer
+    runs-on: windows-2019
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+
+      - uses: actions/download-artifact@v2
+        with:
+          name: installer
+
+      - name: Build image
+        run: |
+          docker build -t msys2-base -f ./.ci/Dockerfile.2019 .
+
+      - name: Test
+        run: |
+          docker run msys2-base C:\msys64\usr\bin\bash.exe -lc "pacman --version"
+          docker run msys2-base C:\msys64\usr\bin\bash.exe -lc "pacman -Qkv"
+          docker run msys2-base C:\msys64\usr\bin\bash.exe -lc "pacman -Syy"
+
+  test-docker-sfx-2016:
+    needs: build-installer
+    runs-on: windows-2016
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+
+      - uses: actions/download-artifact@v2
+        with:
+          name: installer
+
+      - name: Build image
+        run: |
+          docker build -t msys2-base -f ./.ci/Dockerfile.2016 .
+
+      - name: Test
+        run: |
+          docker run msys2-base C:\msys64\usr\bin\bash.exe -lc "pacman --version"
+          docker run msys2-base C:\msys64\usr\bin\bash.exe -lc "pacman -Qkv"
+          docker run msys2-base C:\msys64\usr\bin\bash.exe -lc "pacman -Syy"
+
   upload-nightly:
     permissions:
       contents: write
-    needs: build-installer
+    needs:
+      - build-installer
+      - test-docker-sfx-2019
+      - test-docker-sfx-2016
+      - test-installer-2016
+      - test-installer-2019
     if: github.ref == 'refs/heads/master'
     runs-on: ubuntu-latest
     steps:
@@ -59,31 +162,9 @@ jobs:
         with:
           name: installer
 
-      - name: Create 'latest' Variants
-        run: |
-          cp msys2-base-x86_64-[0-9]*.sfx.exe msys2-base-x86_64-latest.sfx.exe
-          cp msys2-x86_64-[0-9]*.exe msys2-x86_64-latest.exe
-          cp msys2-*.tar.xz msys2-base-x86_64-latest.tar.xz
-
       - uses: eine/tip@master
         with:
           token: ${{ secrets.GITHUB_TOKEN }}
           tag: nightly-x86_64
           rm: true
           files: msys2-*
-
-  build-docker:
-    needs: upload-nightly
-    if: github.ref == 'refs/heads/master'
-    runs-on: windows-latest
-    steps:
-      - name: Checkout code
-        uses: actions/checkout@v2
-
-      - name: Build image
-        run: |
-          Get-Content Dockerfile | docker build -t msys2-base -
-
-      - name: Test
-        run: |
-          docker run msys2-base C:\msys64\usr\bin\bash.exe -lc "pacman --version"