diff --git a/scripts/update_python_zip.py b/scripts/update_python_zip.py
index f5bfba3b0e1b..fa8898b1e8d6 100755
--- a/scripts/update_python_zip.py
+++ b/scripts/update_python_zip.py
@@ -10,6 +10,9 @@
 The port's version, source checksum and patches are read at that vcpkg tag, so the zip matches the
 Python that vcpkg builds. Run it with that Python minor version (e.g. `uv run --python 3.12`), or
 have `uv` on PATH and the script re-runs itself under the right version.
+
+The Windows builds of MREmbeddedPython run it with vcpkg's python.exe to put the zip next to
+python3XY.dll; the repository no longer stores it.
 """
 import argparse
 import hashlib
diff --git a/source/MREmbeddedPython/CMakeLists.txt b/source/MREmbeddedPython/CMakeLists.txt
index 64d36f262c85..d91ea51822fd 100644
--- a/source/MREmbeddedPython/CMakeLists.txt
+++ b/source/MREmbeddedPython/CMakeLists.txt
@@ -35,12 +35,7 @@ IF(MR_PCH)
   target_precompile_headers(${PROJECT_NAME} REUSE_FROM MRPch)
 ENDIF()
 
-# On Windows, copy the zipped Python environment to the output directory.
 IF(WIN32)
-  file(
-    COPY ${MESHLIB_THIRDPARTY_DIR}/python/python${Python_VERSION_MAJOR}${Python_VERSION_MINOR}.zip
-    DESTINATION ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}
-  )
   # The standard library's extension modules (_socket, _ssl, _sqlite3, ...) go to DLLs/, which Python puts on sys.path;
   # the DLLs they need go next to the executable, where most of them already are and the loader finds them
   IF(DEFINED VCPKG_INSTALLED_DIR AND DEFINED VCPKG_TARGET_TRIPLET)
@@ -49,6 +44,20 @@ IF(WIN32)
     file(GLOB PYTHON_EXTENSION_DEPENDENCIES ${PYTHON_DLLS_DIR}/*.dll)
     file(COPY ${PYTHON_EXTENSION_MODULES} DESTINATION ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/DLLs)
     file(COPY ${PYTHON_EXTENSION_DEPENDENCIES} DESTINATION ${CMAKE_RUNTIME_OUTPUT_DIRECTORY})
+
+    # The pure-Python standard library, python3XY.zip, built from the CPython sources of vcpkg's python3 port
+    # by that port's own python.exe; rebuilt only when the script or that Python changes
+    set(VCPKG_PYTHON ${VCPKG_INSTALLED_DIR}/${VCPKG_TARGET_TRIPLET}/tools/python3/python.exe)
+  ENDIF()
+  IF(DEFINED VCPKG_PYTHON AND EXISTS ${VCPKG_PYTHON})
+    set(PYTHON_ZIP_SCRIPT ${CMAKE_CURRENT_SOURCE_DIR}/../../scripts/update_python_zip.py)
+    set(PYTHON_ZIP ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/python${Python_VERSION_MAJOR}${Python_VERSION_MINOR}.zip)
+    add_custom_command(
+      OUTPUT ${PYTHON_ZIP}
+      COMMAND ${VCPKG_PYTHON} ${PYTHON_ZIP_SCRIPT} --output ${PYTHON_ZIP}
+      DEPENDS ${PYTHON_ZIP_SCRIPT} ${VCPKG_PYTHON}
+    )
+    add_custom_target(MREmbeddedPythonZip ALL DEPENDS ${PYTHON_ZIP})
   ENDIF()
 ENDIF()
 
diff --git a/source/MREmbeddedPython/MREmbeddedPython.vcxproj b/source/MREmbeddedPython/MREmbeddedPython.vcxproj
index e66e993dfb12..2cc5fc934cc4 100644
--- a/source/MREmbeddedPython/MREmbeddedPython.vcxproj
+++ b/source/MREmbeddedPython/MREmbeddedPython.vcxproj
@@ -19,9 +19,6 @@
     </ProjectConfiguration>
   </ItemGroup>
   <ItemGroup>
-    <CopyFileToFolders Include="$(ProjectDir)..\..\thirdparty\python\python$(PythonVersion).zip">
-      <FileType>Document</FileType>
-    </CopyFileToFolders>
     <!-- The standard library's extension modules (_socket, _ssl, _sqlite3, ...) go to DLLs\, which Python puts on sys.path; -->
     <!-- the DLLs they need go next to the executable, where most of them already are and the loader finds them -->
     <CopyFileToFolders Include="$(VcpkgCurrentInstalledDir)\tools\python3\DLLs\*.pyd">
@@ -140,6 +137,14 @@
     </Link>
   </ItemDefinitionGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
+  <!-- The pure-Python standard library, python3XY.zip, built from the CPython sources of vcpkg's python3 port
+       by that port's own python.exe; rebuilt only when the script or that Python changes -->
+  <Target Name="BuildPythonZip" AfterTargets="Build"
+          Condition="Exists('$(VcpkgCurrentInstalledDir)\tools\python3\python.exe')"
+          Inputs="$(ProjectDir)..\..\scripts\update_python_zip.py;$(VcpkgCurrentInstalledDir)\tools\python3\python.exe"
+          Outputs="$(OutDir)python$(PythonVersion).zip">
+    <Exec Command="&quot;$(VcpkgCurrentInstalledDir)\tools\python3\python.exe&quot; &quot;$(ProjectDir)..\..\scripts\update_python_zip.py&quot; --output &quot;$(OutDir)python$(PythonVersion).zip&quot;" />
+  </Target>
   <ImportGroup Label="ExtensionTargets">
   </ImportGroup>
 </Project>
\ No newline at end of file
diff --git a/thirdparty/licenses/manifest.json b/thirdparty/licenses/manifest.json
index 865b067416eb..bf773b8de0bc 100644
--- a/thirdparty/licenses/manifest.json
+++ b/thirdparty/licenses/manifest.json
@@ -411,13 +411,14 @@
       "upstream": "https://www.python.org",
       "license_source": "https://raw.githubusercontent.com/python/cpython/3.12/LICENSE",
       "source": {
-        "type": "hash",
-        "track": [
-          "thirdparty/python/python311.zip",
-          "thirdparty/python/python312.zip"
+        "type": "vcpkg-registry",
+        "ports": [
+          "python3"
         ]
       },
-      "version": "35ba61c359222abe"
+      "version": {
+        "python3": "3.12.13#1"
+      }
     },
     {
       "id": "pybind11",
diff --git a/thirdparty/python/python311.zip b/thirdparty/python/python311.zip
deleted file mode 100644
index 5241e9bf51ee..000000000000
Binary files a/thirdparty/python/python311.zip and /dev/null differ
diff --git a/thirdparty/python/python312.zip b/thirdparty/python/python312.zip
deleted file mode 100644
index 3bb978717ca9..000000000000
Binary files a/thirdparty/python/python312.zip and /dev/null differ
diff --git a/thirdparty/python/readme.md b/thirdparty/python/readme.md
deleted file mode 100644
index 7cd17b4e6b5b..000000000000
--- a/thirdparty/python/readme.md
+++ /dev/null
@@ -1,2 +0,0 @@
-python3xy.zip archives from Windows embeddable package (64-bit)
-https://www.python.org/downloads/windows/
\ No newline at end of file