diff --git a/packaging/licenses.sh b/packaging/licenses.sh
index 929d736..47a40bb 100755
--- a/packaging/licenses.sh
+++ b/packaging/licenses.sh
@@ -39,8 +39,17 @@ case $slug in
   ely-pdf)
     put MuPDF "$root/engines/mupdf-src/COPYING"
     # Every third party the MuPDF build compiled in.
-    for part in "$root"/engines/mupdf-build/thirdparty/*; do
-      name=${part##*/}
+    case $(uname) in
+      MINGW* | MSYS*)
+        parts=$(python3 "$root/packaging/windows/mupdf-parts.py" "$root/engines/mupdf-src" parts)
+        families=$(python3 "$root/packaging/windows/mupdf-parts.py" "$root/engines/mupdf-src" fonts)
+        ;;
+      *)
+        parts=$(ls "$root/engines/mupdf-build/thirdparty")
+        families=$(ls "$root/engines/mupdf-build/generated/resources/fonts")
+        ;;
+    esac
+    for name in $parts; do
       found=$(find "$root/engines/mupdf-src/thirdparty/$name" -maxdepth 1 -type f \
         \( -iname 'licen[cs]e*' -o -iname 'copying*' -o -iname '*-license.txt' \))
       [ "$name" = libjpeg ] && found=$root/engines/mupdf-src/thirdparty/libjpeg/README
@@ -49,8 +58,7 @@ case $slug in
       put "MuPDF/$name" $found
     done
     # Every font family MuPDF built into the worker.
-    for part in "$root"/engines/mupdf-build/generated/resources/fonts/*; do
-      name=${part##*/}
+    for name in $families; do
       fonts=$root/engines/mupdf-src/resources/fonts/$name
       found=$(find "$fonts" -maxdepth 1 -type f \( -iname 'licen[cs]e*' -o -iname 'copying*' -o -iname 'notice*' -o -iname 'ofl*' \))
       [ -n "$found" ] || { echo "licenses.sh: no licence for MuPDF's $name fonts" >&2; exit 1; }
diff --git a/packaging/windows/mupdf-parts.py b/packaging/windows/mupdf-parts.py
new file mode 100644
index 0000000..0920053
--- /dev/null
+++ b/packaging/windows/mupdf-parts.py
@@ -0,0 +1,26 @@
+"""Usage: mupdf-parts.py <mupdf-src> parts|fonts; what MSBuild compiled."""
+import re
+import sys
+
+src, what = sys.argv[1], sys.argv[2]
+projects = f"{src}/platform/win32"
+# The libraries build-mupdf.sh links into the worker.
+built = ["libthirdparty", "libextract", "libharfbuzz", "libleptonica", "libmubarcode",
+         "libtesseract", "libmupdf", "libpkcs7"]
+compiled = re.compile(r'<ClCompile Include="\.\.\\\.\.\\thirdparty\\([^\\"]+)\\')
+embedded = re.compile(r'Include="\.\.\\\.\.\\resources\\fonts\\([^\\"]+)\\')
+found = set()
+if what == "parts":
+    for name in built:
+        with open(f"{projects}/{name}.vcxproj", encoding="utf-8") as project:
+            found |= set(compiled.findall(project.read()))
+elif what == "fonts":
+    with open(f"{projects}/libresources.vcxproj", encoding="utf-8") as project:
+        found = set(embedded.findall(project.read()))
+else:
+    sys.exit(f"mupdf-parts.py: parts or fonts, not {what}")
+if not found:
+    sys.exit(f"mupdf-parts.py: no {what} in {projects}")
+# Bash reads these names; Windows would end them CRLF.
+sys.stdout.reconfigure(newline="\n")
+print("\n".join(sorted(found)))