diff --git a/build_release_vs.bat b/build_release_vs.bat
index 78419dadf5..a52d940455 100644
--- a/build_release_vs.bat
+++ b/build_release_vs.bat
@@ -20,6 +20,18 @@ for %%a in (%*) do (
     if "%%a"=="-x" set USE_NINJA=1
 )
 
+@REM Check for clang-cl option (-l). Combined with -x it also builds the deps with
+@REM clang-cl; on the Visual Studio generator it applies to the slicer only, because
+@REM the dependency sub-builds have no toolset to inherit and stay on MSVC.
+set CLANG_ARG=
+set TOOLSET_ARG=
+for %%a in (%*) do (
+    if "%%a"=="-l" (
+        set CLANG_ARG=-DCMAKE_C_COMPILER=clang-cl -DCMAKE_CXX_COMPILER=clang-cl
+        set TOOLSET_ARG=-T ClangCL
+    )
+)
+
 @REM Check for unit-tests option ("tests")
 set BUILD_TESTS=OFF
 for %%a in (%*) do (
@@ -127,12 +139,13 @@ if "%1"=="slicer" (
     GOTO :slicer
 )
 echo "building deps.."
+if defined CLANG_ARG if "%USE_NINJA%"=="0" echo Note: -l needs -x for the dependencies; building them with MSVC.
 
 echo on
 REM Set minimum CMake policy to avoid <3.5 errors
 set CMAKE_POLICY_VERSION_MINIMUM=3.5
 if "%USE_NINJA%"=="1" (
-    cmake ../ -G %CMAKE_GENERATOR% -DCMAKE_BUILD_TYPE=%build_type%
+    cmake ../ -G %CMAKE_GENERATOR% %CLANG_ARG% -DCMAKE_BUILD_TYPE=%build_type%
     cmake --build . --config %build_type% --target deps
 ) else (
     cmake ../ -G %CMAKE_GENERATOR% -A %arch% -DCMAKE_BUILD_TYPE=%build_type%
@@ -151,10 +164,10 @@ cd %build_dir%
 echo on
 set CMAKE_POLICY_VERSION_MINIMUM=3.5
 if "%USE_NINJA%"=="1" (
-    cmake .. -G %CMAKE_GENERATOR% -DORCA_TOOLS=ON %SIG_FLAG% -DBUILD_TESTS=%BUILD_TESTS% -DCMAKE_BUILD_TYPE=%build_type%
+    cmake .. -G %CMAKE_GENERATOR% %CLANG_ARG% -DORCA_TOOLS=ON %SIG_FLAG% -DBUILD_TESTS=%BUILD_TESTS% -DCMAKE_BUILD_TYPE=%build_type%
     cmake --build . --config %build_type% --target all
 ) else (
-    cmake .. -G %CMAKE_GENERATOR% -A %arch% -DORCA_TOOLS=ON %SIG_FLAG% -DBUILD_TESTS=%BUILD_TESTS% -DCMAKE_BUILD_TYPE=%build_type%
+    cmake .. -G %CMAKE_GENERATOR% -A %arch% %TOOLSET_ARG% -DORCA_TOOLS=ON %SIG_FLAG% -DBUILD_TESTS=%BUILD_TESTS% -DCMAKE_BUILD_TYPE=%build_type%
     cmake --build . --config %build_type% --target ALL_BUILD -- -m
 )
 @echo off
diff --git a/deps/Assimp/Assimp.cmake b/deps/Assimp/Assimp.cmake
index 8b4de03b09..9b973a55d5 100644
--- a/deps/Assimp/Assimp.cmake
+++ b/deps/Assimp/Assimp.cmake
@@ -21,6 +21,9 @@ orcaslicer_add_cmake_project(Assimp
     URL ${_assimp_url}
     URL_HASH ${_assimp_hash}
     CMAKE_ARGS
+        # Assimp's ccache support sets the global RULE_LAUNCH_COMPILE, which breaks
+        # the Ninja RC rule. The superbuild forwards CMAKE_<LANG>_COMPILER_LAUNCHER.
+        -DASSIMP_BUILD_USE_CCACHE=OFF
         -DASSIMP_BUILD_TESTS=OFF
         -DASSIMP_BUILD_SAMPLES=OFF
         -DASSIMP_BUILD_ASSIMP_TOOLS=OFF
diff --git a/deps/Boost/Boost.cmake b/deps/Boost/Boost.cmake
index bdd801857e..08b62b9fb8 100644
--- a/deps/Boost/Boost.cmake
+++ b/deps/Boost/Boost.cmake
@@ -24,6 +24,13 @@ if (MSVC AND DEP_DEBUG)
     set(_options "FORWARD_CONFIG")
 endif ()
 
+# Boost.Container's bundled dlmalloc passes int* where the Win32 Interlocked API
+# takes volatile long*; cl compiles that with a warning, clang errors out.
+set(_boost_c_flags_line "")
+if (MSVC AND CMAKE_C_COMPILER_ID STREQUAL "Clang")
+    set(_boost_c_flags_line "-DCMAKE_C_FLAGS:STRING=-Wno-incompatible-pointer-types")
+endif ()
+
 orcaslicer_add_cmake_project(Boost
     ${_options}
     URL "https://github.com/boostorg/boost/releases/download/boost-1.84.0/boost-1.84.0.tar.gz"
@@ -38,6 +45,7 @@ orcaslicer_add_cmake_project(Boost
         "${_context_abi_line}"
         "${_context_arch_line}"
         "${_context_impl_line}"
+        "${_boost_c_flags_line}"
 )
 
-set(DEP_Boost_DEPENDS ZLIB)
\ No newline at end of file
+set(DEP_Boost_DEPENDS ZLIB)
diff --git a/deps/CMakeLists.txt b/deps/CMakeLists.txt
index 8f4bc2a215..c95cdf8d73 100644
--- a/deps/CMakeLists.txt
+++ b/deps/CMakeLists.txt
@@ -157,8 +157,16 @@ endif ()
 function(orcaslicer_add_cmake_project projectname)
     cmake_parse_arguments(P_ARGS "FORWARD_CONFIG" "INSTALL_DIR;BUILD_COMMAND;INSTALL_COMMAND" "CMAKE_ARGS" ${ARGN})
 
+    # MSVC is true for clang-cl as well, so the sub-build toolchain has to key on the
+    # generator. A non-Visual-Studio superbuild passes its own generator down, and with
+    # it the CMAKE_C_COMPILER / CMAKE_CXX_COMPILER forwarded below.
+    set(_dep_msvc_gen FALSE)
+    if (MSVC AND CMAKE_GENERATOR MATCHES "Visual Studio")
+        set(_dep_msvc_gen TRUE)
+    endif ()
+
     set(_configs_line -DCMAKE_BUILD_TYPE:STRING=${CMAKE_BUILD_TYPE})
-    if (_is_multi OR MSVC)
+    if (_is_multi OR _dep_msvc_gen)
         if (P_ARGS_FORWARD_CONFIG)
             set(_configs_line -DCMAKE_BUILD_TYPE:STRING=${CMAKE_BUILD_TYPE})
         elseif (ORCA_INCLUDE_DEBUG_INFO AND NOT DEP_DEBUG)
@@ -174,7 +182,7 @@ function(orcaslicer_add_cmake_project projectname)
         set(_target_config "Release")
     endif()
 
-    if (MSVC)
+    if (_dep_msvc_gen)
       set(_gen CMAKE_GENERATOR "${DEP_MSVC_GEN}" CMAKE_GENERATOR_PLATFORM "${DEP_PLATFORM}")
     else()
       set(_gen "")
@@ -182,7 +190,7 @@ function(orcaslicer_add_cmake_project projectname)
 
     if ($ENV{CMAKE_BUILD_PARALLEL_LEVEL})
       set(_build_j "")  # assume environment will control --build parallel setting
-    elseif(MSVC)
+    elseif(_dep_msvc_gen)
       set(_build_j "/m")
     else()
       set(_build_j "-j${NPROC}")
diff --git a/deps/CURL/CURL.cmake b/deps/CURL/CURL.cmake
index a5ae1b9d00..3d649dfdea 100644
--- a/deps/CURL/CURL.cmake
+++ b/deps/CURL/CURL.cmake
@@ -56,6 +56,18 @@ else()
   set(_curl_static ON)
 endif()
 
+# curl 7.75's configure probes and code rely on C laxness cl allows but clang
+# errors on (implicit function declarations, int* vs u_long* in ioctlsocket),
+# which flips probe results and misconfigures nonblock.c into the AmigaOS
+# IoctlSocket branch. Relax both diagnostics so the probes behave like cl, and
+# pin the camel-case probes off since they only "pass" by implicit declaration.
+set(_curl_c_flags_line "")
+set(_curl_probe_overrides "")
+if (MSVC AND CMAKE_C_COMPILER_ID STREQUAL "Clang")
+  set(_curl_c_flags_line "-DCMAKE_C_FLAGS:STRING=-Wno-implicit-function-declaration -Wno-incompatible-pointer-types")
+  set(_curl_probe_overrides -DHAVE_IOCTLSOCKET_CAMEL=0 -DHAVE_IOCTLSOCKET_CAMEL_FIONBIO=0)
+endif ()
+
 orcaslicer_add_cmake_project(CURL
   # GIT_REPOSITORY      https://github.com/curl/curl.git
   # GIT_TAG             curl-7_75_0
@@ -69,6 +81,8 @@ orcaslicer_add_cmake_project(CURL
     -DBUILD_CURL_EXE:BOOL=OFF
     -DCMAKE_POSITION_INDEPENDENT_CODE=ON
     -DCURL_STATICLIB=${_curl_static}
+    "${_curl_c_flags_line}"
+    ${_curl_probe_overrides}
     ${_curl_platform_flags}
 )
 
diff --git a/deps/Eigen/Eigen.cmake b/deps/Eigen/Eigen.cmake
index 599976debb..2a9cc7105c 100644
--- a/deps/Eigen/Eigen.cmake
+++ b/deps/Eigen/Eigen.cmake
@@ -7,5 +7,20 @@ orcaslicer_add_cmake_project(Eigen
     URL https://gitlab.com/libeigen/eigen/-/archive/5.0.1/eigen-5.0.1.zip
     URL_HASH SHA256=0dbb1f9e3aaad66f352c03227d8c983f6f0b49e0b07e71a7300f4abcc01aee12
     CMAKE_ARGS "${_eigen_extra_flags}"
+        # Only the headers are consumed here. Everything below builds nothing we
+        # use, and all three enable_language(Fortran): test/CMakeLists.txt:9,
+        # lapack/CMakeLists.txt:6 and blas/testing/CMakeLists.txt:2. They default
+        # to ON because the dependency configures as its own top-level project.
+        #
+        # Whether that probe is harmless depends on what CMake finds. The Visual
+        # Studio generator supports no Fortran, so it finds nothing; clang-cl sits
+        # next to the LLVM toolset's flang, which works. MSVC with Ninja finds
+        # Strawberry Perl's MinGW gfortran instead, which the deps build already
+        # requires for OpenSSL, and hands it the MSVC-style /machine:x64 that
+        # MinGW's ld reads as a missing input file. The configure dies there and
+        # takes the rest of the superbuild with it.
+        -DEIGEN_BUILD_TESTING=OFF
+        -DEIGEN_BUILD_BLAS=OFF
+        -DEIGEN_BUILD_LAPACK=OFF
     DEPENDS dep_Boost dep_GMP dep_MPFR
 )
diff --git a/deps/OCCT/0001-OCCT-fix.patch b/deps/OCCT/0001-OCCT-fix.patch
index 27f5db7e0f..d251cc7ab6 100644
--- a/deps/OCCT/0001-OCCT-fix.patch
+++ b/deps/OCCT/0001-OCCT-fix.patch
@@ -1,3 +1,20 @@
+diff --git a/adm/cmake/occt_defs_flags.cmake b/adm/cmake/occt_defs_flags.cmake
+index 00000000..00000001 100644
+--- a/adm/cmake/occt_defs_flags.cmake
++++ b/adm/cmake/occt_defs_flags.cmake
+@@ -134,7 +134,11 @@
+     set (CMAKE_CXX_FLAGS "-std=c++0x ${CMAKE_CXX_FLAGS}")
+   endif()
+   # Optimize size of binaries
+-  set (CMAKE_SHARED_LINKER_FLAGS "-Wl,-s ${CMAKE_SHARED_LINKER_FLAGS}")
++  # clang-cl reports the Clang compiler ID, and OCCT builds shared on Windows,
++  # where the MSVC-style linker gets this flag as an argument it does not know.
++  if (NOT WIN32)
++    set (CMAKE_SHARED_LINKER_FLAGS "-Wl,-s ${CMAKE_SHARED_LINKER_FLAGS}")
++  endif()
+ elseif(MINGW)
+   add_definitions(-D_WIN32_WINNT=0x0601)
+   # _WIN32_WINNT=0x0601 (use Windows 7 SDK)
 diff --git a/CMakeLists.txt b/CMakeLists.txt
 index d98acc0f..28eb8eb4 100644
 --- a/CMakeLists.txt
@@ -168,6 +185,32 @@ index d98acc0f..28eb8eb4 100644
  endforeach()
  
  if (BUILD_SAMPLES_QT)
+diff --git a/adm/cmake/occt_macros.cmake b/adm/cmake/occt_macros.cmake
+index 224c96b1..8c94a1c5 100644
+--- a/adm/cmake/occt_macros.cmake
++++ b/adm/cmake/occt_macros.cmake
+@@ -608,7 +608,7 @@ macro (OCCT_INSERT_CODE_FOR_TARGET)
+   install(CODE "if (\"\${CMAKE_INSTALL_CONFIG_NAME}\" MATCHES \"^([Rr][Ee][Ll][Ee][Aa][Ss][Ee])$\")
+     set (OCCT_INSTALL_BIN_LETTER \"\")
+   elseif (\"\${CMAKE_INSTALL_CONFIG_NAME}\" MATCHES \"^([Rr][Ee][Ll][Ww][Ii][Tt][Hh][Dd][Ee][Bb][Ii][Nn][Ff][Oo])$\")
+-    set (OCCT_INSTALL_BIN_LETTER \"i\")
++    set (OCCT_INSTALL_BIN_LETTER \"\")
+   elseif (\"\${CMAKE_INSTALL_CONFIG_NAME}\" MATCHES \"^([Dd][Ee][Bb][Uu][Gg])$\")
+     set (OCCT_INSTALL_BIN_LETTER \"d\")
+   endif()")
+diff --git a/adm/cmake/occt_toolkit.cmake b/adm/cmake/occt_toolkit.cmake
+index 550e0e2f..7ac1a3b8 100644
+--- a/adm/cmake/occt_toolkit.cmake
++++ b/adm/cmake/occt_toolkit.cmake
+@@ -241,7 +241,7 @@
+     else()
+       set (aReleasePdbConf)
+     endif()
+-    install (FILES  ${CMAKE_BINARY_DIR}/${OS_WITH_BIT}/${COMPILER}/bin\${OCCT_INSTALL_BIN_LETTER}/${PROJECT_NAME}.pdb
++    install (FILES  $<TARGET_PDB_FILE:${PROJECT_NAME}>
+              CONFIGURATIONS Debug ${aReleasePdbConf} RelWithDebInfo
+              DESTINATION "${INSTALL_DIR_BIN}\${OCCT_INSTALL_BIN_LETTER}")
+   endif()
 diff --git a/src/Font/Font_FTFont.cxx b/src/Font/Font_FTFont.cxx
 index 5ae9899f..0a17372b 100644
 --- a/src/Font/Font_FTFont.cxx
diff --git a/deps/OpenSSL/OpenSSL.cmake b/deps/OpenSSL/OpenSSL.cmake
index e43997265b..ddeb680052 100644
--- a/deps/OpenSSL/OpenSSL.cmake
+++ b/deps/OpenSSL/OpenSSL.cmake
@@ -17,10 +17,20 @@ else()
 endif()
 
 if(WIN32)
-    set(_conf_cmd perl Configure )
+    set(_openssl_msvc_env CC=cl CXX=cl RC=rc CL=/FS)
+    # OpenSSL's perl Configure honors the CC environment variable, but the
+    # VC-WIN64A makefile only works with cl (an unquoted clang-cl path with
+    # spaces, e.g. exported by CLion, silently produces no .obj files and the
+    # lib step fails with LNK1181). Pin the upstream toolchain.
+    # Keep rc.exe resolved from the MSVC developer environment as well. The
+    # absolute Windows SDK path contains spaces and OpenSSL 1.1.1 writes it to
+    # the generated nmake file without quoting, which skips .res generation.
+    # /FS serializes access to OpenSSL's shared generated PDB when cl is
+    # driven through nmake from a Ninja configure step.
+    set(_conf_cmd ${CMAKE_COMMAND} -E env ${_openssl_msvc_env} perl Configure )
     set(_cross_comp_prefix_line "")
-    set(_make_cmd nmake)
-    set(_install_cmd nmake install_sw )
+    set(_make_cmd ${CMAKE_COMMAND} -E env ${_openssl_msvc_env} nmake)
+    set(_install_cmd ${CMAKE_COMMAND} -E env ${_openssl_msvc_env} nmake install_sw )
 else()
     if(APPLE)
         set(_conf_cmd export MACOSX_DEPLOYMENT_TARGET=${CMAKE_OSX_DEPLOYMENT_TARGET} && ./Configure -mmacosx-version-min=${CMAKE_OSX_DEPLOYMENT_TARGET})
diff --git a/deps/wxInspector/wxInspector.cmake b/deps/wxInspector/wxInspector.cmake
index 97c3810809..4a5b28407f 100644
--- a/deps/wxInspector/wxInspector.cmake
+++ b/deps/wxInspector/wxInspector.cmake
@@ -1,3 +1,26 @@
+# wxInspector finds wxWidgets through CMake's FindwxWidgets module, which only
+# searches lib/vc*_lib because _WX_TOOL is hardcoded to "vc". A superbuild driven
+# by clang-cl installs wxWidgets into lib/clang_x64_lib, so hand the module the
+# directory wxWidgets actually used, derived the same way wxWidgetsConfig.cmake
+# derives it.
+set(_wxinspector_wx_hints "")
+if (MSVC)
+    if (CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
+        set(_wx_compiler_prefix "clang")
+    else ()
+        set(_wx_compiler_prefix "vc")
+    endif ()
+    set(_wx_arch_suffix "")
+    if (CMAKE_GENERATOR_PLATFORM AND NOT CMAKE_GENERATOR_PLATFORM STREQUAL "Win32")
+        string(TOLOWER "_${CMAKE_GENERATOR_PLATFORM}" _wx_arch_suffix)
+    elseif (CMAKE_SIZEOF_VOID_P EQUAL 8)
+        set(_wx_arch_suffix "_x64")
+    endif ()
+    set(_wxinspector_wx_hints
+        "-DwxWidgets_ROOT_DIR=${DESTDIR}"
+        "-DwxWidgets_LIB_DIR=${DESTDIR}/lib/${_wx_compiler_prefix}${_wx_arch_suffix}_lib")
+endif ()
+
 orcaslicer_add_cmake_project(
     wxInspector
     URL https://github.com/Noisyfox/wxInspector/archive/refs/tags/v1.0.0.zip
@@ -6,6 +29,7 @@ orcaslicer_add_cmake_project(
     CMAKE_ARGS
         -DCMAKE_CXX_FLAGS="-DwxDEBUG_LEVEL=0"
         -DCMAKE_POSITION_INDEPENDENT_CODE=ON
+        ${_wxinspector_wx_hints}
 )
 
 if (MSVC)
diff --git a/deps/wxWidgets/0001-Clang-CL-fix.patch b/deps/wxWidgets/0001-Clang-CL-fix.patch
deleted file mode 100644
index 23bf23b3f4..0000000000
--- a/deps/wxWidgets/0001-Clang-CL-fix.patch
+++ /dev/null
@@ -1,28 +0,0 @@
----
- build/cmake/wxWidgetsConfig.cmake.in | 10 +++++++++-
- 1 file changed, 10 insertions(+), 1 deletion(-)
-
-diff --git a/build/cmake/wxWidgetsConfig.cmake.in b/build/cmake/wxWidgetsConfig.cmake.in
-index 1a83f36..70ad8a4 100644
---- a/build/cmake/wxWidgetsConfig.cmake.in
-+++ b/build/cmake/wxWidgetsConfig.cmake.in
-@@ -58,7 +58,16 @@ if(WIN32_MSVC_NAMING)
-     endif()
- endif()
- 
--include("${CMAKE_CURRENT_LIST_DIR}${wxPLATFORM_LIB_DIR}/@PROJECT_NAME@Targets.cmake")
-+if (CMAKE_CXX_COMPILER_ID STREQUAL "Clang" AND CMAKE_CXX_COMPILER_FRONTEND_VARIANT STREQUAL "MSVC")
-+    if (CMAKE_GENERATOR_PLATFORM STREQUAL "ARM64" OR CMAKE_VS_PLATFORM_NAME STREQUAL "ARM64" OR CMAKE_SYSTEM_PROCESSOR MATCHES "^(ARM64|arm64|aarch64)$")
-+        set(_wx_clang_msvc_lib_dir "vc_arm64_lib")
-+    else()
-+        set(_wx_clang_msvc_lib_dir "vc_x64_lib")
-+    endif()
-+    include("${CMAKE_CURRENT_LIST_DIR}${wxPLATFORM_LIB_DIR}/${_wx_clang_msvc_lib_dir}/@PROJECT_NAME@Targets.cmake")
-+else()
-+    include("${CMAKE_CURRENT_LIST_DIR}${wxPLATFORM_LIB_DIR}/@PROJECT_NAME@Targets.cmake")
-+endif()
- 
- macro(wx_inherit_property source dest name)
-     # property name without _<CONFIG>
---
-2.43.0
diff --git a/deps/wxWidgets/wxWidgets.cmake b/deps/wxWidgets/wxWidgets.cmake
index 07bb31d8be..1e2cc85f78 100644
--- a/deps/wxWidgets/wxWidgets.cmake
+++ b/deps/wxWidgets/wxWidgets.cmake
@@ -28,7 +28,6 @@ orcaslicer_add_cmake_project(
     GIT_SHALLOW ON
     GIT_SUBMODULES 3rdparty/catch 3rdparty/pcre 3rdparty/libwebp
     DEPENDS ${PNG_PKG} ${ZLIB_PKG} ${EXPAT_PKG} ${JPEG_PKG}
-    PATCH_COMMAND git apply --verbose --ignore-space-change --whitespace=fix ${CMAKE_CURRENT_LIST_DIR}/0001-Clang-CL-fix.patch
     CMAKE_ARGS
         -DwxBUILD_PRECOMP=ON
         ${_wx_toolkit}