diff --git a/.github/workflows/libcxx-build-and-test.yaml b/.github/workflows/libcxx-build-and-test.yaml
index 2184ddd49537b..107d23e3573f6 100644
--- a/.github/workflows/libcxx-build-and-test.yaml
+++ b/.github/workflows/libcxx-build-and-test.yaml
@@ -250,10 +250,11 @@ jobs:
         - { config: clang-cl-no-vcruntime, mingw: false }
         - { config: clang-cl-debug, mingw: false }
         - { config: clang-cl-static-crt, mingw: false }
-        - { config: mingw-dll, mingw: true }
-        - { config: mingw-static, mingw: true }
-        - { config: mingw-dll-i686, mingw: true }
-        - { config: mingw-incomplete-sysroot, mingw: true }
+        - { config: mingw-dll, mingw: true, crt: ucrt }
+        - { config: mingw-static, mingw: true, crt: ucrt }
+        - { config: mingw-dll-i686, mingw: true, crt: ucrt }
+        - { config: mingw-incomplete-sysroot, mingw: true, crt: ucrt }
+        - { config: mingw-msvcrt, mingw: true, crt: msvcrt }
     steps:
       - uses: actions/checkout@v4
       - name: Install dependencies
@@ -267,7 +268,7 @@ jobs:
       - name: Install llvm-mingw
         if: ${{ matrix.mingw == true }}
         run: |
-          curl -LO https://github.com/mstorsjo/llvm-mingw/releases/download/20240606/llvm-mingw-20240606-ucrt-x86_64.zip
+          curl -LO https://github.com/mstorsjo/llvm-mingw/releases/download/20240606/llvm-mingw-20240606-${{matrix.crt}}-x86_64.zip
           powershell Expand-Archive llvm-mingw*.zip -DestinationPath .
           del llvm-mingw*.zip
           mv llvm-mingw* c:\llvm-mingw
diff --git a/libcxx/utils/ci/run-buildbot b/libcxx/utils/ci/run-buildbot
index 3df7b00a8aa09..4bc9be39d1a38 100755
--- a/libcxx/utils/ci/run-buildbot
+++ b/libcxx/utils/ci/run-buildbot
@@ -772,6 +772,15 @@ mingw-incomplete-sysroot)
     step "Building the runtimes"
     ${NINJA} -vC "${BUILD_DIR}"
 ;;
+mingw-msvcrt)
+    # All tests don't pass in msvcrt based configurations (and we don't have
+    # the right XFAIL markings for it yet), thus initially only test building.
+    clean
+    generate-cmake \
+          -C "${MONOREPO_ROOT}/libcxx/cmake/caches/MinGW.cmake"
+    step "Building the runtimes"
+    ${NINJA} -vC "${BUILD_DIR}"
+;;
 aix)
     clean
     generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/AIX.cmake" \