diff --git a/win/build-deps.cmd b/win/build-deps.cmd
index 581cc4fbda..f096395e42 100644
--- a/win/build-deps.cmd
+++ b/win/build-deps.cmd
@@ -869,7 +869,7 @@ set DEPENDENCY_INSTALL_DIR=%INSTALL_DIR%\manifold-%MANIFOLD_VERSION%
 set NEXT_DEPENDENCY_LABEL=Successful
 :: TODO: test whether manifold links the debug CRT for Debug builds and needs separate
 :: Release/Debug install dirs instead of sharing one.
-echo MANIFOLD_ROOT=%DEPENDENCY_INSTALL_DIR%>>"%~dp0\%BUILD_DEPS_CACHE_PATH%"
+echo MANIFOLD_INSTALL_PATH=%DEPENDENCY_INSTALL_DIR%>>"%~dp0\%BUILD_DEPS_CACHE_PATH%"
 
 IF EXIST "%DEPENDENCY_INSTALL_DIR%" (
     echo Found existing "%DEPENDENCY_INSTALL_DIR%", skipping
diff --git a/win/run-cmake.bat b/win/run-cmake.bat
index 3620445c2c..bb8e90275f 100755
--- a/win/run-cmake.bat
+++ b/win/run-cmake.bat
@@ -158,6 +158,7 @@ echo    TBB_INSTALL_DIR         = %TBB_INSTALL_DIR%
 echo    USD_INSTALL_DIR         = %USD_INSTALL_DIR%
 echo    ROCKSDB_INSTALL_DIR     = %ROCKSDB_INSTALL_DIR%
 echo    ZSTD_INSTALL_DIR        = %ZSTD_INSTALL_DIR%
+echo    MANIFOLD_INSTALL_PATH   = %MANIFOLD_INSTALL_PATH%
 echo    QT_DIR                  = %QT_DIR%
 echo    QT_HOST_PATH            = %QT_HOST_PATH%
 echo    CCACHE_INSTALL_DIR      = %CCACHE_INSTALL_DIR%
@@ -176,12 +177,17 @@ set CMAKE_PREFIX_PATH=%CMAKE_PREFIX_PATH%;%BOOST_INSTALL_DIR%;%CCACHE_INSTALL_DI
 set CMake_PREFIX_PATH=%CMAKE_PREFIX_PATH%;%USD_INSTALL_DIR%;%TBB_INSTALL_DIR%
 set CMAKE_PREFIX_PATH=%CMAKE_PREFIX_PATH%;%OCC_INSTALL_DIR%;%CGAL_INSTALL_DIR%
 set CMAKE_PREFIX_PATH=%CMAKE_PREFIX_PATH%;%GMP_INSTALL_DIR%;%MPFR_INSTALL_DIR%
+:: TODO: drop this TRANSITION check once everyone has re-run build-deps.cmd with manifold support.
+if defined MANIFOLD_INSTALL_PATH set CMAKE_PREFIX_PATH=%CMAKE_PREFIX_PATH%;%MANIFOLD_INSTALL_PATH%
 if defined QT_DIR set CMAKE_PREFIX_PATH=%CMAKE_PREFIX_PATH%;%QT_DIR%
 
 set QT_DIR_OPTION=
 if defined QT_DIR set QT_DIR_OPTION=-DQT_DIR="%QT_DIR%"
 set QT_HOST_PATH_OPTION=
 if defined QT_HOST_PATH set QT_HOST_PATH_OPTION=-DQT_HOST_PATH="%QT_HOST_PATH%"
+:: TODO: drop this TRANSITION check once everyone has re-run build-deps.cmd with manifold support.
+set WITH_MANIFOLD_OPTION=
+if defined MANIFOLD_INSTALL_PATH set WITH_MANIFOLD_OPTION=-DWITH_MANIFOLD=ON
 
 :: Not fully supported - not available from install-ifcopenshell
 :: and some logs are still showing Visual Studio generators.
@@ -200,6 +206,7 @@ cmake.exe %CMAKELISTS_DIR% -G %GENERATOR% %ARCH_OPTION% ^
     -DCMAKE_PREFIX_PATH="%CMAKE_PREFIX_PATH%" ^
     %QT_DIR_OPTION% ^
     %QT_HOST_PATH_OPTION% ^
+    %WITH_MANIFOLD_OPTION% ^
     -DADD_COMMIT_SHA=%ADD_COMMIT_SHA% -DVERSION_OVERRIDE=%VERSION_OVERRIDE% ^
     %ARGUMENTS%