diff --git a/src/Pure/Admin/build_verit.scala b/src/Pure/Admin/build_verit.scala
--- a/src/Pure/Admin/build_verit.scala
+++ b/src/Pure/Admin/build_verit.scala
@@ -1,160 +1,167 @@
 /*  Title:      Pure/Admin/build_csdp.scala
     Author:     Makarius
 
 Build Isabelle veriT component from official download.
 */
 
 package isabelle
 
 
 object Build_VeriT
 {
   val default_download_url = "https://verit.loria.fr/rmx/2020.10/verit-2020.10-rmx.tar.gz"
 
 
   /* build veriT */
 
   def build_verit(
     download_url: String = default_download_url,
     verbose: Boolean = false,
     progress: Progress = new Progress,
-    target_dir: Path = Path.current)
+    target_dir: Path = Path.current,
+    mingw: MinGW = MinGW.none)
   {
+    mingw.check
+
     Isabelle_System.with_tmp_dir("build")(tmp_dir =>
     {
       /* component */
 
       val Archive_Name = """^.*?([^/]+)$""".r
       val Version = """^[^-]+-(.+)\.tar.gz$""".r
 
       val archive_name =
         download_url match {
           case Archive_Name(name) => name
           case _ => error("Failed to determine source archive name from " + quote(download_url))
         }
 
       val version =
         archive_name match {
           case Version(version) => version
           case _ => error("Failed to determine component version from " + quote(archive_name))
         }
 
       val component_name = "verit-" + version
       val component_dir = Isabelle_System.new_directory(target_dir + Path.basic(component_name))
       progress.echo("Component " + component_dir)
 
 
       /* platform */
 
       val platform_name =
+        proper_string(Isabelle_System.getenv("ISABELLE_WINDOWS_PLATFORM64")) orElse
         proper_string(Isabelle_System.getenv("ISABELLE_PLATFORM64")) getOrElse
         error("No 64bit platform")
 
       val platform_dir = Isabelle_System.make_directory(component_dir + Path.basic(platform_name))
 
 
       /* download source */
 
       val archive_path = tmp_dir + Path.basic(archive_name)
       Isabelle_System.download(download_url, archive_path, progress = progress)
 
       Isabelle_System.bash("tar xzf " + File.bash_path(archive_path), cwd = tmp_dir.file).check
       val source_name = File.get_dir(tmp_dir)
 
       Isabelle_System.bash(
         "tar xzf " + archive_path + " && mv " + Bash.string(source_name) + " src",
         cwd = component_dir.file).check
 
 
       /* build */
 
       progress.echo("Building veriT for " + platform_name + " ...")
 
       val configure_options =
         if (Platform.is_linux) "LDFLAGS=-Wl,-rpath,_DUMMY_" else ""
 
       val build_dir = tmp_dir + Path.basic(source_name)
-      progress.bash("set -e\n./configure " + configure_options + "\nmake",
+      progress.bash(mingw.bash_script("set -e\n./configure " + configure_options + "\nmake"),
         cwd = build_dir.file, echo = verbose).check
 
 
       /* install */
 
       File.copy(build_dir + Path.explode("LICENSE"), component_dir)
 
       val exe_path = Path.basic("veriT").platform_exe
       File.copy(build_dir + exe_path, platform_dir)
-      Executable.libraries_closure(platform_dir + exe_path, filter = Set("libgmp"))
+      Executable.libraries_closure(platform_dir + exe_path, filter = Set("libgmp"), mingw = mingw)
 
 
       /* settings */
 
       val etc_dir = Isabelle_System.make_directory(component_dir + Path.basic("etc"))
       File.write(etc_dir + Path.basic("settings"),
         """# -*- shell-script -*- :mode=shellscript:
 
-VERIT_HOME="$COMPONENT/$ISABELLE_PLATFORM64"
+VERIT_HOME="$COMPONENT/${ISABELLE_WINDOWS_PLATFORM64:-$ISABELLE_PLATFORM64}"
 VERIT_VERSION=""" + quote(version) + """
 
 VERIT_SOLVER="$VERIT_HOME/veriT"
 
 if [ -e "$VERIT_HOME" ]
 then
   VERIT_INSTALLED="yes"
 fi
 """)
 
 
       /* README */
 
       File.write(component_dir + Path.basic("README"),
 """This is veriT """ + version + """ from
 """ + download_url + """
 
 It has been built from sources like this:
 
   cd src
   ./configure
   make
 
 
         Makarius
         """ + Date.Format.date(Date.now()) + "\n")
     })
 }
 
 
   /* Isabelle tool wrapper */
 
   val isabelle_tool =
     Isabelle_Tool("build_verit", "build prover component from official download",
     args =>
     {
       var target_dir = Path.current
+      var mingw = MinGW.none
       var download_url = default_download_url
       var verbose = false
 
       val getopts = Getopts("""
 Usage: isabelle build_verit [OPTIONS]
 
   Options are:
     -D DIR       target directory (default ".")
+    -M DIR       msys/mingw root specification for Windows
     -U URL       download URL
                  (default: """" + default_download_url + """")
     -v           verbose
 
   Build prover component from official download.
 """,
         "D:" -> (arg => target_dir = Path.explode(arg)),
+        "M:" -> (arg => mingw = MinGW(Path.explode(arg))),
         "U:" -> (arg => download_url = arg),
         "v" -> (_ => verbose = true))
 
       val more_args = getopts(args)
       if (more_args.nonEmpty) getopts.usage()
 
       val progress = new Console_Progress()
 
       build_verit(download_url = download_url, verbose = verbose, progress = progress,
-        target_dir = target_dir)
+        target_dir = target_dir, mingw = mingw)
     })
 }