diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 7bab94e..ed5a8e9 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -83,3 +83,31 @@ jobs:
       - name: Build and Test
         run: |
           swift test --enable-test-discovery
+
+  windows:
+    runs-on: windows-latest
+
+    steps:
+      - uses: actions/checkout@v2
+      - uses: seanmiddleditch/gha-setup-vsdevenv@master
+
+      - name: Install swift-5.5 (2021-04-19 SNAPSHOT)
+        run: |
+          Install-Binary -Url "https://swift.org/builds/swift-5.5-branch/windows10/swift-5.5-DEVELOPMENT-SNAPSHOT-2021-04-19-a/swift-5.5-DEVELOPMENT-SNAPSHOT-2021-04-19-a-windows10.exe" -Name "installer.exe" -ArgumentList ("-q")
+      - name: Set Environment Variables
+        run: |
+          echo "SDKROOT=C:\Library\Developer\Platforms\Windows.platform\Developer\SDKs\Windows.sdk" | Out-File -FilePath $env:GITHUB_ENV -Encoding utf8 -Append
+          echo "DEVELOPER_DIR=C:\Library\Developer" | Out-File -FilePath $env:GITHUB_ENV -Encoding utf8 -Append
+      - name: Adjust Paths
+        run: |
+          echo "C:\Library\Swift-development\bin;C:\Library\icu-67\usr\bin" | Out-File -FilePath $env:GITHUB_PATH -Encoding utf8 -Append
+          echo "C:\Library\Developer\Toolchains\unknown-Asserts-development.xctoolchain\usr\bin" | Out-File -FilePath $env:GITHUB_PATH -Encoding utf8 -Append
+      - name: Install Supporting Files
+        run: |
+          Copy-Item "$env:SDKROOT\usr\share\ucrt.modulemap" -destination "$env:UniversalCRTSdkDir\Include\$env:UCRTVersion\ucrt\module.modulemap"
+          Copy-Item "$env:SDKROOT\usr\share\visualc.modulemap" -destination "$env:VCToolsInstallDir\include\module.modulemap"
+          Copy-Item "$env:SDKROOT\usr\share\visualc.apinotes" -destination "$env:VCToolsInstallDir\include\visualc.apinotes"
+          Copy-Item "$env:SDKROOT\usr\share\winsdk.modulemap" -destination "$env:UniversalCRTSdkDir\Include\$env:UCRTVersion\um\module.modulemap"
+
+      - name: Build and Test
+        run: swift test --enable-test-discovery -Xcc -IC:\Library\Developer\Toolchains\unknown-Asserts-development.xctoolchain\usr\include -Xlinker -LC:\Library\Developer\Toolchains\unknown-Asserts-development.xctoolchain\usr\lib
diff --git a/Package@swift-5.5.swift b/Package@swift-5.5.swift
index 65acbee..2e502c0 100644
--- a/Package@swift-5.5.swift
+++ b/Package@swift-5.5.swift
@@ -16,7 +16,7 @@ let package = Package(
         // Dependencies declare other packages that this package depends on.
         .package(name: "SwiftSyntax",
                  url: "https://github.com/apple/swift-syntax.git",
-                 .revision("release/5.5")),
+                 .revision("4ae758ab85ed2a5d3e3e8b5050a8ce52179bd102")),
     ],
     targets: [
         // Targets are the basic building blocks of a package. A target can define a module or a test suite.