diff --git a/.github/workflows/cmake-multi-platform.yml b/.github/workflows/cmake-multi-platform.yml
index 57639632..e7250e81 100644
--- a/.github/workflows/cmake-multi-platform.yml
+++ b/.github/workflows/cmake-multi-platform.yml
@@ -230,3 +230,47 @@ jobs:
         -S ${{ github.workspace }}
     - name: Build
       run: cmake --build ${{ github.workspace }}/build
+
+  windows:
+    # Twelve source files carry WIN32 or _MSC_VER guards and nothing has
+    # compiled them for as long as the workflows have existed, so a change
+    # that breaks the Windows path is invisible until a consumer reports
+    # it. zlib comes from vcpkg because the project requires it.
+    name: windows-latest msvc ${{ matrix.linkage }}
+    runs-on: windows-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - linkage: static
+            shared: "OFF"
+            triplet: x64-windows-static
+          - linkage: shared
+            shared: "ON"
+            triplet: x64-windows
+    steps:
+    - uses: actions/checkout@v4
+    - name: Install zlib and expat
+      run: vcpkg install zlib:${{ matrix.triplet }} expat:${{ matrix.triplet }}
+    - name: Configure CMake
+      shell: pwsh
+      run: |
+        $toolchain = Join-Path $env:VCPKG_INSTALLATION_ROOT 'scripts/buildsystems/vcpkg.cmake'
+        Write-Host "vcpkg toolchain: $toolchain"
+        if (-not (Test-Path $toolchain)) { throw "toolchain file not found: $toolchain" }
+        cmake -B "${{ github.workspace }}/build" `
+          -DCMAKE_TOOLCHAIN_FILE="$toolchain" `
+          -DVCPKG_TARGET_TRIPLET=${{ matrix.triplet }} `
+          -DBUILD_SHARED_LIBS=${{ matrix.shared }} `
+          -DCMAKE_RUNTIME_OUTPUT_DIRECTORY="${{ github.workspace }}/build/bin" `
+          -DNIFTI_BUILD_APPLICATIONS=ON `
+          -DUSE_NIFTI2_CODE=ON `
+          -DUSE_CIFTI_CODE=ON `
+          -S "${{ github.workspace }}"
+    - name: Build
+      run: cmake --build ${{ github.workspace }}/build --config Release
+    - name: Test
+      working-directory: ${{ github.workspace }}/build
+      # A test that cannot find a DLL can raise a modal dialog and block the
+      # runner rather than exit, so every test carries a timeout.
+      run: ctest --build-config Release --output-on-failure --no-tests=ignore --timeout 120
diff --git a/cifti/afni_xml.h b/cifti/afni_xml.h
index ecc4ab3e..16d0ae7c 100644
--- a/cifti/afni_xml.h
+++ b/cifti/afni_xml.h
@@ -70,38 +70,62 @@ typedef struct {
 } afni_xml_control;
 
 
+#ifndef CIF_API
+   #if defined(_WIN32) || defined(__CYGWIN__)
+      #if defined(CIFTI_BUILD_SHARED)
+      #ifdef __GNUC__
+         #define CIF_API __attribute__ ((dllexport))
+      #else
+         #define CIF_API __declspec( dllexport )
+      #endif
+      #elif defined(CIFTI_USE_SHARED)
+      #ifdef __GNUC__
+         #define CIF_API __attribute__ ((dllimport))
+      #else
+         #define CIF_API __declspec( dllimport )
+      #endif
+      #else
+      #define CIF_API
+      #endif
+   #elif (defined(__GNUC__) && __GNUC__ >= 4) || defined(__clang__)
+      #define CIF_API __attribute__ ((visibility ("default")))
+   #else
+      #define CIF_API
+   #endif
+#endif
+
 /* --------------------------- prototypes --------------------------------- */
 
 /* main interface */
-afni_xml_list axml_read_buf (const char * buf_in, int64_t bin_len);
-afni_xml_list axml_read_file(const char * fname, int read_data);
+CIF_API afni_xml_list axml_read_buf (const char * buf_in, int64_t bin_len);
+CIF_API afni_xml_list axml_read_file(const char * fname, int read_data);
 
-int axml_disp_xlist( const char *mesg, afni_xml_list * axlist, int verb);
-int axml_disp_xml_t( const char *mesg, afni_xml_t * ax, int indent, int verb);
+CIF_API int axml_disp_xlist( const char *mesg, afni_xml_list * axlist, int verb);
+CIF_API int axml_disp_xml_t( const char *mesg, afni_xml_t * ax, int indent, int verb);
 
 
 /* create/free */
-afni_xml_t * new_afni_xml   (const char * name);
-int          axml_add_attrs (afni_xml_t * ax, const char ** attr);
-int          axml_free_xml_t(afni_xml_t * ax);
-int          axml_free_xlist(afni_xml_list * axlist);
-
-char * axml_attr_value(afni_xml_t * ax, const char * name);
-int    axml_recur(int(*func)(FILE*,afni_xml_t*,int), afni_xml_t * ax);
-afni_xml_t * axml_recur_find_xml(int (*func)(afni_xml_t *, int), afni_xml_t * ax,
+CIF_API afni_xml_t * new_afni_xml   (const char * name);
+CIF_API int          axml_add_attrs (afni_xml_t * ax, const char ** attr);
+CIF_API int          axml_free_xml_t(afni_xml_t * ax);
+CIF_API int          axml_free_xlist(afni_xml_list * axlist);
+
+CIF_API char * axml_attr_value(afni_xml_t * ax, const char * name);
+CIF_API int    axml_recur(int(*func)(FILE*,afni_xml_t*,int), afni_xml_t * ax);
+CIF_API afni_xml_t * axml_recur_find_xml(int (*func)(afni_xml_t *, int), afni_xml_t * ax,
                                  int depth, int max_depth);
 
 
 /* control API */
-int    axml_set_verb        ( int val  );
-int    axml_get_verb        ( void     );
-int    axml_set_dstore      ( int val  );
-int    axml_get_dstore      ( void     );
-int    axml_set_indent      ( int val  );
-int    axml_get_indent      ( void     );
-int    axml_set_buf_size    ( int val  );
-int    axml_get_buf_size    ( void     );
-int    axml_set_wstream     ( FILE *fp );
-FILE * axml_get_wstream     ( void     );
+CIF_API int    axml_set_verb        ( int val  );
+CIF_API int    axml_get_verb        ( void     );
+CIF_API int    axml_set_dstore      ( int val  );
+CIF_API int    axml_get_dstore      ( void     );
+CIF_API int    axml_set_indent      ( int val  );
+CIF_API int    axml_get_indent      ( void     );
+CIF_API int    axml_set_buf_size    ( int val  );
+CIF_API int    axml_get_buf_size    ( void     );
+CIF_API int    axml_set_wstream     ( FILE *fp );
+CIF_API FILE * axml_get_wstream     ( void     );
 
 #endif /* AFNI_XML_H */
diff --git a/cifti/afni_xml_io.h b/cifti/afni_xml_io.h
index ae8aeb2a..ee9b6a1b 100644
--- a/cifti/afni_xml_io.h
+++ b/cifti/afni_xml_io.h
@@ -50,29 +50,6 @@
     - convert as in SUMA_Create_Fake_CIFTI()
  * ----------------------------------------------------------------------*/
 
-#ifndef CIF_API
-   #if defined(_WIN32) || defined(__CYGWIN__)
-      #if defined(CIFTI_BUILD_SHARED)
-      #ifdef __GNUC__
-         #define CIF_API __attribute__ ((dllexport))
-      #else
-         #define CIF_API __declspec( dllexport )
-      #endif
-      #elif defined(CIFTI_USE_SHARED)
-      #ifdef __GNUC__
-         #define CIF_API __attribute__ ((dllimport))
-      #else
-         #define CIF_API __declspec( dllimport )
-      #endif
-      #else
-      #define CIF_API
-      #endif
-   #elif (defined(__GNUC__) && __GNUC__ >= 4) || defined(__clang__)
-      #define CIF_API __attribute__ ((visibility ("default")))
-   #else
-      #define CIF_API
-   #endif
-#endif
 
 /* --------------------------- structures --------------------------------- */