Index: libcxx/utils/ci/buildkite-pipeline.yml
===================================================================
--- libcxx/utils/ci/buildkite-pipeline.yml
+++ libcxx/utils/ci/buildkite-pipeline.yml
@@ -277,6 +277,20 @@
         - exit_status: -1  # Agent was lost
           limit: 2
 
+  - label: "Windows"
+    command: "\"\\Program Files\\Git\\usr\\bin\\bash\" libcxx/utils/ci/run-buildbot generic-win"
+    artifact_paths:
+      - "**/test-results.xml"
+    agents:
+      name: "w16e2-1"
+      queue: "windows"
+    retry:
+      automatic:
+        - exit_status: -1  # Agent was lost
+          limit: 2
+    soft_fail:
+        - exit_status: 1
+
   # All jobs defined before this `wait` will run whenever a CI job is started.
   # Jobs defined after the `wait` will run only if all the jobs above succeeded.
   # We use this to reduce the load on testers that have more constrained resources
Index: libcxx/utils/ci/run-buildbot
===================================================================
--- libcxx/utils/ci/run-buildbot
+++ libcxx/utils/ci/run-buildbot
@@ -421,6 +421,36 @@
     generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Armv7Thumb-noexceptions.cmake"
     check-cxx-cxxabi
 ;;
+generic-win)
+    clean
+    # Add bash to the path; the current CI runner doesn't have it added
+    # globally.
+    export PATH="$PATH:/c/Program Files/Git/usr/bin"
+
+    # -D_LIBCPP_HAS_NO_INT128 allows building filesystem with a MSVC
+    # setup that lacks the necessary builtins for int128.
+
+    # -loldnames is needed for some tests unless using Clang 12 (the
+    # CI runner has Clang 11 currently).
+
+    # -DLIBCXX_ENABLE_EXPERIMENTAL_LIBRARY=NO is needed, as the testsuite
+    # fails to link that library if enabled, in a DLL build.
+
+    echo "--- Generating CMake"
+    cmake -S "${MONOREPO_ROOT}/libcxx" \
+          -B "${BUILD_DIR}" \
+          -GNinja -DCMAKE_MAKE_PROGRAM="${NINJA}" \
+          -DCMAKE_BUILD_TYPE=RelWithDebInfo \
+          -DCMAKE_C_COMPILER=clang-cl \
+          -DCMAKE_CXX_COMPILER=clang-cl \
+          -DLLVM_LIT_ARGS="-sv --show-unsupported --xunit-xml-output test-results.xml" \
+          -DLIBCXX_ENABLE_EXPERIMENTAL_LIBRARY=NO \
+          -DLIBCXX_ENABLE_FILESYSTEM=YES \
+          -DCMAKE_CXX_FLAGS="-D_LIBCPP_HAS_NO_INT128" \
+          -DLIBCXX_TEST_LINKER_FLAGS="-loldnames"
+    echo "+++ Running the libc++ tests"
+    ${NINJA} -C "${BUILD_DIR}" check-cxx
+;;
 *)
     echo "${BUILDER} is not a known configuration"
     exit 1