diff --git a/build.sh b/build.sh
index 8d647deedb..e6d0d096f6 100755
--- a/build.sh
+++ b/build.sh
@@ -39,6 +39,7 @@ HAVE_QT=1
 HAVE_PNG=0
 HAVE_CURL=0
 HAVE_EXPAT=0
+HAVE_GIT2=1
 
 RUBYINCLUDE=""
 RUBYINCLUDE2=""
@@ -209,6 +210,9 @@ while [ "$*" != "" ]; do
   -libexpat)
     HAVE_EXPAT=1
     ;;
+  -nolibgit2)
+    HAVE_GIT2=0
+    ;;
   -qt5)
     echo "*** WARNING: -qt5 option is ignored - Qt version is auto-detected now."
     ;;
@@ -265,6 +269,7 @@ while [ "$*" != "" ]; do
     echo "  -libcurl              Use libcurl instead of QtNetwork (for Qt<4.7)"
     echo "  -libexpat             Use libexpat instead of QtXml"
     echo "  -libpng               Use libpng instead of Qt for PNG generation"
+    echo "  -nolibgit2            Do not include libgit2 for Git package support"
     echo ""
     echo "Environment Variables:"
     echo ""
@@ -495,6 +500,9 @@ fi
 if [ $HAVE_PNG != 0 ]; then
   echo "    Uses libpng for PNG generation"
 fi
+if [ $HAVE_GIT2 != 0 ]; then
+  echo "    Uses libgit2 for Git access"
+fi
 if [ "$RPATH" = "" ]; then
   RPATH="$BIN"
 fi
@@ -578,6 +586,7 @@ echo "      HAVE_64BIT_COORD=$HAVE_64BIT_COORD"
 echo "      HAVE_CURL=$HAVE_CURL"
 echo "      HAVE_PNG=$HAVE_PNG"
 echo "      HAVE_EXPAT=$HAVE_EXPAT"
+echo "      HAVE_GIT2=$HAVE_GIT2"
 echo "      RPATH=$RPATH"
 
 mkdir -p $BUILD
@@ -650,6 +659,7 @@ qmake_options=(
   HAVE_CURL="$HAVE_CURL"
   HAVE_EXPAT="$HAVE_EXPAT"
   HAVE_PNG="$HAVE_PNG"
+  HAVE_GIT2="$HAVE_GIT2"
   PREFIX="$BIN"
   RPATH="$RPATH"
   KLAYOUT_VERSION="$KLAYOUT_VERSION"
diff --git a/scripts/makedeb.sh b/scripts/makedeb.sh
index 81fc8291d3..204266666f 100755
--- a/scripts/makedeb.sh
+++ b/scripts/makedeb.sh
@@ -19,16 +19,16 @@ fi
 # TODO: derive this list automatically?
 case $target in
 ubuntu16)
-  depends="libqt4-designer (>= 4.8.6), libqt4-xml (>= 4.8.6), libqt4-sql (>= 4.8.6), libqt4-network (>= 4.8.6), libqtcore4 (>= 4.8.6), libqtgui4 (>= 4.8.6), zlib1g (>= 1.2.8), libruby2.3 (>= 2.3.1), python3 (>= 3.5.1), libpython3.5 (>= 3.5.1), libstdc++6 (>= 4.6.3), libc6 (>= 2.15)"
+  depends="libqt4-designer (>= 4.8.6), libqt4-xml (>= 4.8.6), libqt4-sql (>= 4.8.6), libqt4-network (>= 4.8.6), libqtcore4 (>= 4.8.6), libqtgui4 (>= 4.8.6), zlib1g (>= 1.2.8), libgit2-24 (>= 0.24.0), libruby2.3 (>= 2.3.1), python3 (>= 3.5.1), libpython3.5 (>= 3.5.1), libstdc++6 (>= 4.6.3), libc6 (>= 2.15)"
   ;;
 ubuntu18)
-  depends="libqt4-designer (>= 4.8.7), libqt4-xml (>= 4.8.7), libqt4-sql (>= 4.8.7), libqt4-network (>= 4.8.7), libqtcore4 (>= 4.8.7), libqtgui4 (>= 4.8.7), zlib1g (>= 1.2.11), libruby2.5 (>= 2.5.1), python3 (>= 3.6.5), libpython3.6 (>= 3.6.5), libstdc++6 (>= 8), libc6 (>= 2.27)"
+  depends="libqt4-designer (>= 4.8.7), libqt4-xml (>= 4.8.7), libqt4-sql (>= 4.8.7), libqt4-network (>= 4.8.7), libqtcore4 (>= 4.8.7), libqtgui4 (>= 4.8.7), zlib1g (>= 1.2.11), libgit2-26 (>= 0.26.0), libruby2.5 (>= 2.5.1), python3 (>= 3.6.5), libpython3.6 (>= 3.6.5), libstdc++6 (>= 8), libc6 (>= 2.27)"
   ;;
 ubuntu20)
-  depends="libqt5core5a (>= 5.12.8), libqt5designer5 (>= 5.12.8), libqt5gui5 (>= 5.12.8), libqt5multimedia5 (>= 5.12.8), libqt5multimediawidgets5 (>= 5.12.8), libqt5network5 (>= 5.12.8), libqt5opengl5 (>= 5.12.8), libqt5printsupport5 (>= 5.12.8), libqt5sql5 (>= 5.12.8), libqt5svg5 (>= 5.12.8), libqt5widgets5 (>= 5.12.8), libqt5xml5 (>= 5.12.8), libqt5xmlpatterns5 (>= 5.12.8), zlib1g (>= 1.2.11), libruby2.7 (>= 2.7.0), python3 (>= 3.8.2), libpython3.8 (>= 3.8.2), libstdc++6 (>=10), libc6 (>= 2.31)" 
+  depends="libqt5core5a (>= 5.12.8), libqt5designer5 (>= 5.12.8), libqt5gui5 (>= 5.12.8), libqt5multimedia5 (>= 5.12.8), libqt5multimediawidgets5 (>= 5.12.8), libqt5network5 (>= 5.12.8), libqt5opengl5 (>= 5.12.8), libqt5printsupport5 (>= 5.12.8), libqt5sql5 (>= 5.12.8), libqt5svg5 (>= 5.12.8), libqt5widgets5 (>= 5.12.8), libqt5xml5 (>= 5.12.8), libqt5xmlpatterns5 (>= 5.12.8), zlib1g (>= 1.2.11), libgit2-28 (>= 0.28.4), libruby2.7 (>= 2.7.0), python3 (>= 3.8.2), libpython3.8 (>= 3.8.2), libstdc++6 (>=10), libc6 (>= 2.31)" 
   ;;
 ubuntu22)
-  depends="libqt5core5a (>= 5.15.3), libqt5designer5 (>= 5.15.3), libqt5gui5 (>= 5.15.3), libqt5multimedia5 (>= 5.15.3), libqt5multimediawidgets5 (>= 5.15.3), libqt5network5 (>= 5.15.3), libqt5opengl5 (>= 5.15.3), libqt5printsupport5 (>= 5.15.3), libqt5sql5 (>= 5.15.3), libqt5svg5 (>= 5.15.3), libqt5widgets5 (>= 5.15.3), libqt5xml5 (>= 5.15.3), libqt5xmlpatterns5 (>= 5.15.3), zlib1g (>= 1.2.11), libruby3.0 (>= 3.0.2), python3 (>= 3.10.4), libpython3.10 (>= 3.10.4), libstdc++6 (>=12), libc6 (>= 2.35)" 
+  depends="libqt5core5a (>= 5.15.3), libqt5designer5 (>= 5.15.3), libqt5gui5 (>= 5.15.3), libqt5multimedia5 (>= 5.15.3), libqt5multimediawidgets5 (>= 5.15.3), libqt5network5 (>= 5.15.3), libqt5opengl5 (>= 5.15.3), libqt5printsupport5 (>= 5.15.3), libqt5sql5 (>= 5.15.3), libqt5svg5 (>= 5.15.3), libqt5widgets5 (>= 5.15.3), libqt5xml5 (>= 5.15.3), libqt5xmlpatterns5 (>= 5.15.3), zlib1g (>= 1.2.11), libgit2-1.1 (>= 1.1.0), libruby3.0 (>= 3.0.2), python3 (>= 3.10.4), libpython3.10 (>= 3.10.4), libstdc++6 (>=12), libc6 (>= 2.35)" 
   ;;
 *)
   echo "Unknown target '$target' (given as first argument)"
diff --git a/scripts/rpm-data/klayout.spec b/scripts/rpm-data/klayout.spec
index 1ad64705f7..5a9bad6f24 100644
--- a/scripts/rpm-data/klayout.spec
+++ b/scripts/rpm-data/klayout.spec
@@ -53,6 +53,7 @@ Requires: qt5-qttools-devel >= 5.11.1
 Requires:	ruby >= 2.0.0
 Requires:	python3 >= 3.6.0
 Requires: qt-x11 >= 4.8.5
+Requires: libgit2 >= 0.26.8
 %define buildopt -j2
 %endif
 
@@ -62,7 +63,7 @@ Requires: libcurl >= 7.19.7
 Requires: ruby >= 1.8.7
 Requires: python >= 2.6.6
 Requires: qt-x11 >= 4.6.2
-%define buildopt -libcurl -j2
+%define buildopt -libcurl -j2 -nolibgit2
 %endif
 
 %if "%{target_system}" == "opensuse42_2"
@@ -70,7 +71,7 @@ Requires: qt-x11 >= 4.6.2
 Requires:	ruby2.3 >= 2.3.1
 Requires:	python3 >= 3.4.6
 Requires: libqt4-x11 >= 4.8.6
-%define buildopt -j2
+%define buildopt -j2 -nolibgit2
 %endif
 
 %if "%{target_system}" == "opensuse42_3"
@@ -78,13 +79,14 @@ Requires: libqt4-x11 >= 4.8.6
 Requires:	ruby2.3 >= 2.3.1
 Requires:	python3 >= 3.4.6
 Requires: libqt4-x11 >= 4.8.6
-%define buildopt -j2
+%define buildopt -j2 -nolibgit2
 %endif
 
 %if "%{target_system}" == "opensuse15"
 # OpenSuSE Leap 15 requirements
 Requires:	ruby >= 2.5
 Requires:	python3 >= 3.6
+Requires:	libgit2 >= 1.3.0
 Requires: libqt5-qtbase >= 5.15.2
 Requires: libQt5PrintSupport5 >= 5.15.2
 Requires: libQt5Designer5 >= 5.15.2
diff --git a/setup.py b/setup.py
index 744b465477..cc195adb58 100644
--- a/setup.py
+++ b/setup.py
@@ -422,15 +422,12 @@ def macros(self):
         macros = [
             ("HAVE_CURL", 1),
             ("HAVE_EXPAT", 1),
+            ("HAVE_PNG", 1),
             ("KLAYOUT_MAJOR_VERSION", self.major_version()),
             ("KLAYOUT_MINOR_VERSION", self.minor_version()),
             ("GSI_ALIAS_INSPECT", 1),
         ]
 
-        if platform.system() == "Darwin" and check_libpng():
-                macros += [("HAVE_PNG", 1)]
-        else:
-            macros += [("HAVE_PNG", 1)]
         return macros
 
     def minor_version(self):
diff --git a/src/db/db/db.pro b/src/db/db/db.pro
index 6914e12fa4..513cca3a01 100644
--- a/src/db/db/db.pro
+++ b/src/db/db/db.pro
@@ -404,7 +404,7 @@ HEADERS = \
   dbShapeCollection.h \
   dbShapeCollectionUtils.h
 
-!equals(HAVE_QT, "0") || !equals(HAVE_PYTHON, "0") {
+!equals(HAVE_QT, "0") {
 
   RESOURCES = \
     dbResources.qrc \
diff --git a/src/drc/drc/drc.pro b/src/drc/drc/drc.pro
index c43e875d03..2304dc1327 100644
--- a/src/drc/drc/drc.pro
+++ b/src/drc/drc/drc.pro
@@ -13,7 +13,7 @@ HEADERS = \
   drcCommon.h \
   drcForceLink.h \
 
-!equals(HAVE_QT, "0") || !equals(HAVE_PYTHON, "0") {
+!equals(HAVE_QT, "0") {
   RESOURCES = \
     drcResources.qrc
 }
diff --git a/src/klayout.pri b/src/klayout.pri
index 0cb25c0ab2..27a7051a05 100644
--- a/src/klayout.pri
+++ b/src/klayout.pri
@@ -103,6 +103,15 @@ equals(HAVE_PTHREADS, "1") {
   DEFINES += HAVE_PTHREADS
 }
 
+equals(HAVE_GIT2, "1") {
+  !isEmpty(BITS_PATH) {
+    include($$BITS_PATH/git2/git2.pri)
+  } else {
+    LIBS += -lgit2
+  }
+  DEFINES += HAVE_GIT2
+}
+
 equals(HAVE_RUBY, "1") {
   !isEmpty(BITS_PATH) {
     include($$BITS_PATH/ruby/ruby.pri)
diff --git a/src/lay/lay/lay.pro b/src/lay/lay/lay.pro
index 3500502b89..23295c1f8f 100644
--- a/src/lay/lay/lay.pro
+++ b/src/lay/lay/lay.pro
@@ -33,6 +33,7 @@ HEADERS = \
     layResourceHelpProvider.h \
     layRuntimeErrorForm.h \
     layReaderErrorForm.h \
+    laySaltParsedURL.h \
     laySearchReplaceConfigPage.h \
     laySearchReplaceDialog.h \
     laySearchReplacePropertiesWidgets.h \
@@ -144,6 +145,7 @@ SOURCES = \
     layResourceHelpProvider.cc \
     layRuntimeErrorForm.cc \
     layReaderErrorForm.cc \
+    laySaltParsedURL.cc \
     laySearchReplaceConfigPage.cc \
     laySearchReplaceDialog.cc \
     laySearchReplacePlugin.cc \
diff --git a/src/lay/lay/layApplication.cc b/src/lay/lay/layApplication.cc
index e7c54f7687..1b008fb7a6 100644
--- a/src/lay/lay/layApplication.cc
+++ b/src/lay/lay/layApplication.cc
@@ -770,7 +770,7 @@ ApplicationBase::init_app ()
     size_t local_folders = (lay::get_appdata_path ().empty () ? 0 : 1);
 
     for (std::vector <std::string>::const_iterator p = m_klayout_path.begin (); p != m_klayout_path.end (); ++p) {
-      if (p - m_klayout_path.begin () < local_folders) {
+      if (size_t (p - m_klayout_path.begin ()) < local_folders) {
         mc->add_path (*p, tl::to_string (QObject::tr ("Local")), std::string (), false);
       } else if (m_klayout_path.size () == 1 + local_folders) {
         mc->add_path (*p, tl::to_string (QObject::tr ("Global")), std::string (), true);
diff --git a/src/lay/lay/layInit.cc b/src/lay/lay/layInit.cc
index 18e423c3ae..ec108ab79f 100644
--- a/src/lay/lay/layInit.cc
+++ b/src/lay/lay/layInit.cc
@@ -152,7 +152,7 @@ void init (const std::vector<std::string> &_paths)
         try {
           s_plugins.push_back (do_load_plugin (imp));
           modules.insert (*im);
-        } catch (tl::Exception (&ex)) {
+        } catch (tl::Exception &ex) {
           tl::error << ex.msg ();
         }
       }
diff --git a/src/lay/lay/laySalt.cc b/src/lay/lay/laySalt.cc
index d6fcd501f7..efb77844e1 100644
--- a/src/lay/lay/laySalt.cc
+++ b/src/lay/lay/laySalt.cc
@@ -21,11 +21,18 @@
 */
 
 #include "laySalt.h"
+#include "laySaltParsedURL.h"
+
 #include "tlString.h"
 #include "tlFileUtils.h"
 #include "tlLog.h"
 #include "tlInternational.h"
 #include "tlWebDAV.h"
+#include "tlEnv.h"
+#if defined(HAVE_GIT2)
+#  include "tlGit.h"
+#endif
+
 #include "lymMacro.h"
 
 #include <QFileInfo>
@@ -63,6 +70,13 @@ Salt::root ()
   return m_root;
 }
 
+bool
+Salt::download_package_information () const
+{
+  //  $KLAYOUT_ALWAYS_DOWNLOAD_PACKAGE_INFO
+  return tl::app_flag ("always-download-package-info") || m_root.sparse ();
+}
+
 Salt::flat_iterator
 Salt::begin_flat ()
 {
@@ -483,11 +497,27 @@ Salt::create_grain (const SaltGrain &templ, SaltGrain &target, double timeout, t
 
   } else if (! templ.url ().empty ()) {
 
-    if (templ.url ().find ("http:") == 0 || templ.url ().find ("https:") == 0) {
+    lay::SaltParsedURL purl (templ.url ());
+
+    if (purl.url ().find ("http:") == 0 || purl.url ().find ("https:") == 0) {
 
-      //  otherwise download from the URL
-      tl::info << QObject::tr ("Downloading package from '%1' to '%2' ..").arg (tl::to_qstring (templ.url ())).arg (tl::to_qstring (target.path ()));
-      res = tl::WebDAVObject::download (templ.url (), target.path (), timeout, callback);
+      //  otherwise download from the URL using Git or SVN
+
+      if (purl.protocol () == Git) {
+
+#if defined(HAVE_GIT2)
+        tl::info << QObject::tr ("Downloading package from '%1' to '%2' using Git protocol (ref='%3', subdir='%4') ..").arg (tl::to_qstring (purl.url ())).arg (tl::to_qstring (target.path ())).arg (tl::to_qstring (purl.branch ())).arg (tl::to_qstring (purl.subfolder ()));
+        res = tl::GitObject::download (purl.url (), target.path (), purl.subfolder (), purl.branch (), timeout, callback);
+#else
+        throw tl::Exception (tl::to_string (QObject::tr ("Unable to install package '%1' - git protocol not compiled in").arg (tl::to_qstring (target.name ()))));
+#endif
+
+      } else if (purl.protocol () == WebDAV || purl.protocol () == DefaultProtocol) {
+
+        tl::info << QObject::tr ("Downloading package from '%1' to '%2' using SVN/WebDAV protocol ..").arg (tl::to_qstring (purl.url ())).arg (tl::to_qstring (target.path ()));
+        res = tl::WebDAVObject::download (purl.url (), target.path (), timeout, callback);
+
+      }
 
     } else {
 
diff --git a/src/lay/lay/laySalt.h b/src/lay/lay/laySalt.h
index 7970862a32..71c5a69d00 100644
--- a/src/lay/lay/laySalt.h
+++ b/src/lay/lay/laySalt.h
@@ -199,6 +199,11 @@ Q_OBJECT
    */
   SaltGrains &root ();
 
+  /**
+   *  @brief Gets a value indicating whether the collection wants package information to be downloaded always
+   */
+  bool download_package_information () const;
+
 signals:
   /**
    *  @brief A signal triggered before one of the collections changed
diff --git a/src/lay/lay/laySaltController.cc b/src/lay/lay/laySaltController.cc
index 7c99e30db6..51b53ae663 100644
--- a/src/lay/lay/laySaltController.cc
+++ b/src/lay/lay/laySaltController.cc
@@ -23,6 +23,7 @@
 #include "laySaltController.h"
 #include "laySaltManagerDialog.h"
 #include "laySaltDownloadManager.h"
+#include "laySaltParsedURL.h"
 #include "layConfig.h"
 #include "layMainWindow.h"
 #include "layQtTools.h"
@@ -142,7 +143,7 @@ SaltController::show_editor ()
     {
       //  while running the dialog, don't watch file events - that would interfere with
       //  the changes applied by the dialog itself.
-      lay::BusySection busy_section;  //  disable file watcher
+      tl::FileSystemWatcherDisabled disable_file_watcher;  //  disable file watcher
       mp_salt_dialog->exec ();
     }
 
@@ -156,7 +157,7 @@ SaltController::show_editor ()
 void
 SaltController::sync_file_watcher ()
 {
-  lay::BusySection busy_section;  //  disable file watcher
+  tl::FileSystemWatcherDisabled disable_file_watcher;  //  disable file watcher
 
   if (m_file_watcher) {
     m_file_watcher->clear ();
@@ -202,12 +203,19 @@ SaltController::install_packages (const std::vector<std::string> &packages, bool
       }
     }
 
-    if (n.find ("http:") == 0 || n.find ("https:") == 0 || n.find ("file:") == 0 || n[0] == '/' || n[0] == '\\') {
+    lay::SaltParsedURL purl (n);
+    const std::string &url = purl.url ();
+
+    if (url.find ("http:") == 0 || url.find ("https:") == 0 || url.find ("file:") == 0 || url[0] == '/' || url[0] == '\\') {
+
       //  its a URL
       manager.register_download (std::string (), std::string (), n, v);
+
     } else {
+
       //  its a plain name
       manager.register_download (n, std::string (), std::string (), v);
+
     }
 
   }
@@ -223,7 +231,7 @@ SaltController::install_packages (const std::vector<std::string> &packages, bool
   {
     //  while running the dialog, don't watch file events - that would interfere with
     //  the changes applied by the dialog itself.
-    lay::BusySection busy_section;  //  disable file watcher
+    tl::FileSystemWatcherDisabled disable_file_watcher;  //  disable file watcher
     result = manager.execute (0, m_salt);
   }
 
diff --git a/src/lay/lay/laySaltDownloadManager.cc b/src/lay/lay/laySaltDownloadManager.cc
index e104e3531b..559b593336 100644
--- a/src/lay/lay/laySaltDownloadManager.cc
+++ b/src/lay/lay/laySaltDownloadManager.cc
@@ -27,6 +27,7 @@
 #include "tlFileUtils.h"
 #include "tlWebDAV.h"
 #include "tlLog.h"
+#include "tlEnv.h"
 
 #include <memory>
 #include <QTreeWidgetItem>
@@ -310,42 +311,81 @@ SaltDownloadManager::fetch_missing (const lay::Salt &salt, const lay::Salt &salt
       ++progress;
 
       //  Add URL and token from the package index
+      //
+      //  In order to do so, we try to use the information from that package index as far as possible.
+      //  Downloading a package definition from the original package URL may be expensive in case of
+      //  large GIT repositories.
+      //
+      //  Downloading is required if:
+      //  - A package download is requested without a name (package can't be looked up in the package index)
+      //  - Or a name is given, but not found in the package index
+      //
+      //  Downloading can be bypassed if the package index (salt mine) specifies "sparse=false".
+      //  In that case, the package index will have all information about the package.
+
       if (! p->name.empty ()) {
 
         const lay::SaltGrain *g = salt_mine.grain_by_name (p->name);
         if (! g) {
           if (p->url.empty ()) {
-            throw tl::Exception (tl::to_string (QObject::tr ("Package '%1' not found in index - cannot resolve download URL").arg (tl::to_qstring (p->name))));
+            throw tl::Exception (tl::to_string (tr ("Package '%s' not found in index - cannot resolve download URL")), p->name);
           }
         } else {
           if (p->url.empty ()) {
             if (tl::verbosity() >= 20) {
-              tl::log << "Resolved package URL for package " << p->name << ": " << g->url ();
+              tl::log << tr ("Resolved package URL for package") << " '" << p->name << "': " << g->url ();
             }
             p->url = g->url ();
           }
           p->token = g->token ();
+          p->grain = *g;
+          p->downloaded = true;
         }
 
       }
 
-      try {
-        p->grain = SaltGrain::from_url (p->url);
-      } catch (tl::Exception &ex) {
-        throw tl::Exception (tl::to_string (QObject::tr ("Error fetching spec file for package '%1': %2").arg (tl::to_qstring (p->name)).arg (tl::to_qstring (ex.msg ()))));
-      }
+      if (! p->downloaded && salt_mine.download_package_information ()) {
+
+        //  If requested, download package information to complete information from index or dependencies
+        if (tl::verbosity() >= 10) {
+          tl::log << tl::sprintf (tl::to_string (tr ("Reading package description for package '%s' from: '%s")), p->name, p->url);
+        }
+        try {
+          p->grain = SaltGrain::from_url (p->url);
+          p->downloaded = true;
+        } catch (tl::Exception &ex) {
+          throw tl::Exception (tl::to_string (tr ("Error fetching spec file for package from '%s': %s")), p->url, ex.msg ());
+        }
 
-      if (p->version.empty ()) {
-        p->version = p->grain.version ();
       }
 
-      p->name = p->grain.name ();
-      p->downloaded = true;
+      if (! p->downloaded) {
+
+        if (p->name.empty ()) {
+          throw tl::Exception (tl::to_string (tr ("No name given package from '%s' (from dependencies or command line installation request)")), p->url);
+        }
+
+        if (tl::verbosity() >= 10) {
+          tl::warn << tl::sprintf (tl::to_string (tr ("Package '%s' not downloaded from: %s. Dependencies may not be resolved.")), p->name, p->url);
+        }
+
+      } else {
+
+        if (p->version.empty ()) {
+          p->version = p->grain.version ();
+        }
+        if (p->name.empty ()) {
+          p->name = p->grain.name ();
+        }
+
+        if (SaltGrain::compare_versions (p->grain.version (), p->version) < 0) {
+          throw tl::Exception (tl::to_string (tr ("Package '%s': package in repository is too old (%s) to satisfy requirements (%s)")), p->name, p->grain.version (), p->version);
+        }
 
-      if (SaltGrain::compare_versions (p->grain.version (), p->version) < 0) {
-        throw tl::Exception (tl::to_string (QObject::tr ("Package '%1': package in repository is too old (%2) to satisfy requirements (%3)").arg (tl::to_qstring (p->name)).arg (tl::to_qstring (p->grain.version ())).arg (tl::to_qstring (p->version))));
       }
 
+      p->downloaded = true;
+
     }
 
   }
diff --git a/src/lay/lay/laySaltGrain.cc b/src/lay/lay/laySaltGrain.cc
index 932ceb3100..cd54e841f9 100644
--- a/src/lay/lay/laySaltGrain.cc
+++ b/src/lay/lay/laySaltGrain.cc
@@ -22,11 +22,15 @@
 
 #include "laySaltGrain.h"
 #include "laySaltController.h"
+#include "laySaltParsedURL.h"
 #include "tlString.h"
 #include "tlXMLParser.h"
 #include "tlHttpStream.h"
-#include "tlWebDAV.h"
 #include "tlFileUtils.h"
+#include "tlWebDAV.h"
+#if defined(HAVE_GIT2)
+#  include "tlGit.h"
+#endif
 
 #include <memory>
 #include <QDir>
@@ -65,7 +69,8 @@ SaltGrain::operator== (const SaltGrain &other) const
          m_license == other.m_license &&
          m_hidden == other.m_hidden &&
          m_authored_time == other.m_authored_time &&
-         m_installed_time == other.m_installed_time;
+         m_installed_time == other.m_installed_time
+      ;
 }
 
 void
@@ -253,18 +258,10 @@ SaltGrain::compare_versions (const std::string &v1, const std::string &v2)
   }
 }
 
-std::string
-SaltGrain::spec_url (const std::string &url)
+const std::string &
+SaltGrain::spec_file ()
 {
-  std::string res = url;
-  if (! res.empty()) {
-    //  TODO: use system path separator unless this is a URL
-    if (res [res.size () - 1] != '/') {
-      res += "/";
-    }
-    res += grain_filename;
-  }
-  return res;
+  return grain_filename;
 }
 
 bool
@@ -512,14 +509,21 @@ SaltGrain::from_path (const std::string &path)
 }
 
 tl::InputStream *
-SaltGrain::stream_from_url (std::string &url, double timeout, tl::InputHttpStreamCallback *callback)
+SaltGrain::stream_from_url (std::string &generic_url, double timeout, tl::InputHttpStreamCallback *callback)
 {
-  if (url.empty ()) {
+  if (generic_url.empty ()) {
     throw tl::Exception (tl::to_string (QObject::tr ("No download link available")));
   }
 
+  if (tl::verbosity () >= 20) {
+    tl::info << tr ("Downloading package info from ") << generic_url;
+  }
+
+  lay::SaltParsedURL purl (generic_url);
+  const std::string &url = purl.url ();
+
   //  base relative URL's on the salt mine URL
-  if (url.find ("http:") != 0 && url.find ("https:") != 0 && url.find ("file:") != 0 && !url.empty() && url[0] != '/' && url[0] != '\\' && lay::SaltController::instance ()) {
+  if (purl.protocol () == lay::DefaultProtocol && url.find ("http:") != 0 && url.find ("https:") != 0 && url.find ("file:") != 0 && !url.empty() && url[0] != '/' && url[0] != '\\' && lay::SaltController::instance ()) {
 
     //  replace the last component ("repository.xml") by the given path
     QUrl sami_url (tl::to_qstring (lay::SaltController::instance ()->salt_mine_url ()));
@@ -529,15 +533,27 @@ SaltGrain::stream_from_url (std::string &url, double timeout, tl::InputHttpStrea
     }
     sami_url.setPath (path_comp.join (QString::fromUtf8 ("/")));
 
-    url = tl::to_string (sami_url.toString ());
+    //  return the full path as a file path, not an URL
+    generic_url = tl::to_string (sami_url.toString ());
 
   }
 
-  std::string spec_url = SaltGrain::spec_url (url);
-  if (spec_url.find ("http:") == 0 || spec_url.find ("https:") == 0) {
-    return tl::WebDAVObject::download_item (spec_url, timeout, callback);
+  if (url.find ("http:") == 0 || url.find ("https:") == 0) {
+
+    if (purl.protocol () == lay::Git) {
+#if defined(HAVE_GIT2)
+      return tl::GitObject::download_item (url, SaltGrain::spec_file (), purl.subfolder (), purl.branch (), timeout, callback);
+#else
+      throw tl::Exception (tl::to_string (QObject::tr ("Cannot download from Git - Git support not compiled in")));
+#endif
+    } else {
+      return tl::WebDAVObject::download_item (url + "/" + SaltGrain::spec_file (), timeout, callback);
+    }
+
   } else {
-    return new tl::InputStream (spec_url);
+
+    return new tl::InputStream (url);
+
   }
 }
 
diff --git a/src/lay/lay/laySaltGrain.h b/src/lay/lay/laySaltGrain.h
index 92ef33e192..bf0f2ef90f 100644
--- a/src/lay/lay/laySaltGrain.h
+++ b/src/lay/lay/laySaltGrain.h
@@ -49,6 +49,9 @@ namespace lay
  */
 struct SaltGrainDependency
 {
+  SaltGrainDependency ()
+  { }
+
   std::string name;
   std::string url;
   std::string version;
@@ -466,6 +469,8 @@ class LAY_PUBLIC SaltGrain
    *  This method will return a grain constructed from the downloaded data.
    *  The data is read from "URL/grain.xml". This method will throw an
    *  exception if an error occurs during reading.
+   *
+   *  CAUTION: with GIT protocol and large repositories, this function may be very expensive.
    */
   static SaltGrain from_url (const std::string &url, double timeout = 60.0, tl::InputHttpStreamCallback *callback = 0);
 
@@ -474,13 +479,15 @@ class LAY_PUBLIC SaltGrain
    *  The stream is a new'd object and needs to be deleted by the caller.
    *  "url" is the download URL on input and gets modified to match the
    *  actual URL if it is a relative one.
+   *
+   *  CAUTION: with GIT protocol and large repositories, this function may be very expensive.
    */
   static tl::InputStream *stream_from_url (std::string &url, double timeout = 60.0, tl::InputHttpStreamCallback *callback = 0);
 
   /**
-   *  @brief Forms the spec file download URL from a given download URL
+   *  @brief Gets the name of the spec file ("grain.xml")
    */
-  static std::string spec_url (const std::string &url);
+  static const std::string &spec_file ();
 
   /**
    *  @brief Returns a value indicating whether the given path represents is a grain
diff --git a/src/lay/lay/laySaltGrainPropertiesDialog.cc b/src/lay/lay/laySaltGrainPropertiesDialog.cc
index 7a3f098b9d..061eee1ca2 100644
--- a/src/lay/lay/laySaltGrainPropertiesDialog.cc
+++ b/src/lay/lay/laySaltGrainPropertiesDialog.cc
@@ -25,6 +25,7 @@
 #include "tlString.h"
 #include "tlExceptions.h"
 #include "tlHttpStream.h"
+#include "tlEnv.h"
 
 #include <QFileDialog>
 #include <QFileInfo>
@@ -43,6 +44,14 @@ namespace lay
 
 // ----------------------------------------------------------------------------------------------------
 
+static bool download_package_information ()
+{
+  //  $KLAYOUT_ALWAYS_DOWNLOAD_PACKAGE_INFO
+  return tl::app_flag ("always-download-package-info");
+}
+
+// ----------------------------------------------------------------------------------------------------
+
 /**
  *  @brief A delegate for editing a field of the dependency list
  */
@@ -583,7 +592,7 @@ SaltGrainPropertiesDialog::accept ()
                                   << tr ("If the dependency package has a version itself, the version is automatically set to its current version.");
     }
 
-    if (!d->url.empty ()) {
+    if (!d->url.empty () && download_package_information ()) {
       SaltGrain gdep;
       try {
         gdep = SaltGrain::from_url (d->url);
diff --git a/src/lay/lay/laySaltGrains.cc b/src/lay/lay/laySaltGrains.cc
index bacb19d5fa..846d8052c1 100644
--- a/src/lay/lay/laySaltGrains.cc
+++ b/src/lay/lay/laySaltGrains.cc
@@ -34,6 +34,7 @@ namespace lay
 {
 
 SaltGrains::SaltGrains ()
+  : m_sparse (true)
 {
   //  .. nothing yet ..
 }
@@ -54,6 +55,12 @@ SaltGrains::set_name (const std::string &n)
   m_name = n;
 }
 
+void
+SaltGrains::set_sparse (const bool &f)
+{
+  m_sparse = f;
+}
+
 void
 SaltGrains::set_title (const std::string &t)
 {
@@ -302,6 +309,7 @@ SaltGrains::consolidate ()
 
 static tl::XMLElementList s_group_struct =
   tl::make_member (&SaltGrains::name, &SaltGrains::set_name, "name") +
+  tl::make_member (&SaltGrains::sparse, &SaltGrains::set_sparse, "sparse") +
   tl::make_member (&SaltGrains::include, "include") +
   tl::make_element (&SaltGrains::begin_collections, &SaltGrains::end_collections, &SaltGrains::add_collection, "group", &s_group_struct) +
   tl::make_element (&SaltGrains::begin_grains, &SaltGrains::end_grains, &SaltGrains::add_grain, "salt-grain", SaltGrain::xml_elements ());
@@ -354,6 +362,9 @@ SaltGrains::include (const std::string &src_in)
 
     lay::SaltGrains g;
     g.load (src);
+    if (g.sparse ()) {
+      m_sparse = true;
+    }
     m_collections.splice (m_collections.end (), g.m_collections);
     m_grains.splice (m_grains.end (), g.m_grains);
 
diff --git a/src/lay/lay/laySaltGrains.h b/src/lay/lay/laySaltGrains.h
index a277e78638..c43e5fbafa 100644
--- a/src/lay/lay/laySaltGrains.h
+++ b/src/lay/lay/laySaltGrains.h
@@ -78,6 +78,24 @@ class LAY_PUBLIC SaltGrains
    */
   void set_name (const std::string &p);
 
+  /**
+   *  @brief Gets a value indicating that the information in the grain collection is sparse
+   *
+   *  If this flag is set to true (the default), the information in the collection needs
+   *  to be completed by pulling the original definition of the grain for the grain's URL.
+   *  If the flag is false, the information is complete and reflects the grain's original
+   *  definition.
+   */
+  const bool &sparse () const
+  {
+    return m_sparse;
+  }
+
+  /**
+   *  @brief Sets a value indicating that the information in the grain collection is sparse
+   */
+  void set_sparse (const bool &f);
+
   /**
    *  @brief Gets the title of the grain collection
    *
@@ -225,6 +243,7 @@ class LAY_PUBLIC SaltGrains
   collections_type m_collections;
   grains_type m_grains;
   std::string m_url;
+  bool m_sparse;
 };
 
 }
diff --git a/src/lay/lay/laySaltManagerDialog.cc b/src/lay/lay/laySaltManagerDialog.cc
index f439be7b80..4e86323bde 100644
--- a/src/lay/lay/laySaltManagerDialog.cc
+++ b/src/lay/lay/laySaltManagerDialog.cc
@@ -30,11 +30,13 @@
 #include "ui_SaltGrainTemplateSelectionDialog.h"
 #include "tlString.h"
 #include "tlExceptions.h"
+#include "tlEnv.h"
 
 #include "rba.h"
 #include "pya.h"
 
 #include <QTextDocument>
+#include <QApplication>
 #include <QPainter>
 #include <QDir>
 #include <QTextStream>
@@ -289,7 +291,9 @@ SaltManagerDialog::SaltManagerDialog (QWidget *parent, lay::Salt *salt, const st
   : QDialog (parent),
     m_salt_mine_url (salt_mine_url),
     dm_update_models (this, &SaltManagerDialog::update_models), m_current_tab (-1),
-    mp_downloaded_target (0)
+    mp_downloaded_target (0),
+    dm_mine_update_selected_changed (this, &SaltManagerDialog::do_mine_update_selected_changed),
+    dm_mine_new_selected_changed (this, &SaltManagerDialog::do_mine_new_selected_changed)
 {
   Ui::SaltManagerDialog::setupUi (this);
   mp_properties_dialog = new lay::SaltGrainPropertiesDialog (this);
@@ -845,6 +849,8 @@ SaltManagerDialog::salt_mine_about_to_change ()
 void
 SaltManagerDialog::refresh ()
 {
+  m_salt_grain_cache.clear ();
+
   if (! m_salt_mine_url.empty ()) {
 
     tl::log << tl::to_string (tr ("Downloading package repository from %1").arg (tl::to_qstring (m_salt_mine_url)));
@@ -1094,8 +1100,12 @@ SaltManagerDialog::current_grains ()
 void
 SaltManagerDialog::mine_update_selected_changed ()
 {
-BEGIN_PROTECTED
+  dm_mine_update_selected_changed ();
+}
 
+void
+SaltManagerDialog::do_mine_update_selected_changed ()
+{
   SaltModel *model = dynamic_cast <SaltModel *> (salt_mine_view_update->model ());
   tl_assert (model != 0);
 
@@ -1108,15 +1118,17 @@ BEGIN_PROTECTED
   details_update_frame->setEnabled (g != 0);
 
   get_remote_grain_info (g, details_update_text);
-
-END_PROTECTED
 }
 
 void
 SaltManagerDialog::mine_new_selected_changed ()
 {
-BEGIN_PROTECTED
+  dm_mine_new_selected_changed ();
+}
 
+void
+SaltManagerDialog::do_mine_new_selected_changed ()
+{
   SaltModel *model = dynamic_cast <SaltModel *> (salt_mine_view_new->model ());
   tl_assert (model != 0);
 
@@ -1129,8 +1141,73 @@ BEGIN_PROTECTED
   details_new_frame->setEnabled (g != 0);
 
   get_remote_grain_info (g, details_new_text);
+}
+
+namespace
+{
+
+/**
+ * @brief A callback to keep the UI alive (mainly used for Git grain retrieval)
+ */
+class ProcessEventCallback
+  : public tl::InputHttpStreamCallback
+{
+public:
+  virtual void wait_for_input ()
+  {
+    QApplication::processEvents (QEventLoop::ExcludeUserInputEvents);
+  }
+};
+
+class FetchGrainInfoProgressAdaptor
+  : public tl::ProgressAdaptor
+{
+public:
+  FetchGrainInfoProgressAdaptor (SaltGrainDetailsTextWidget *details, const std::string &name, const QString &html)
+    : mp_details (details), m_name (name), m_html (html)
+  {
+    mp_details->setHtml (m_html.arg (QString ()));
+    m_counter = 0;
+  }
+
+  virtual void yield (tl::Progress *progress)
+  {
+    QCoreApplication::processEvents (QEventLoop::ExcludeUserInputEvents | QEventLoop::WaitForMoreEvents, 100);
+
+    ++m_counter;
+    std::string all_dots = "..........";
+    m_counter = m_counter % all_dots.size ();
+    std::string dots = std::string (all_dots, 0, m_counter);
+    mp_details->setHtml (m_html.arg (tl::to_qstring (tl::sprintf (tl::to_string (tr ("Downloading %.0f%% %s")), progress->value (), dots))));
+  }
+
+  virtual void trigger (tl::Progress * /*progress*/)
+  {
+    //  .. nothing yet ..
+  }
+
+  void error ()
+  {
+    mp_details->setHtml (m_html.arg (QString ()));
+  }
+
+  void success ()
+  {
+    mp_details->setHtml (m_html.arg (QString ()));
+  }
+
+  bool is_aborted () const
+  {
+    return false;
+  }
+
+private:
+  lay::SaltGrainDetailsTextWidget *mp_details;
+  std::string m_name;
+  QString m_html;
+  unsigned int m_counter;
+};
 
-END_PROTECTED
 }
 
 void
@@ -1141,68 +1218,104 @@ SaltManagerDialog::get_remote_grain_info (lay::SaltGrain *g, SaltGrainDetailsTex
     return;
   }
 
+  tl_assert (m_downloaded_grain.get () == 0);
+
   m_downloaded_grain.reset (0);
+
   if (m_downloaded_grain_reader.get ()) {
-    //  NOTE: don't delete the reader in the slot it triggered
     m_downloaded_grain_reader->close ();
   }
+  m_downloaded_grain_reader.reset (0);
+
   mp_downloaded_target = details;
   m_salt_mine_grain.reset (new lay::SaltGrain (*g));
 
-  //  Download actual grain definition file
-  try {
+  if (m_salt_mine.download_package_information () && m_salt_mine.grain_by_name (g->name ())) {
 
-    if (g->url ().empty ()) {
-      throw tl::Exception (tl::to_string (tr ("No download link available")));
-    }
+    //  Download actual grain definition file
+    try {
 
-    QString html = tr (
-      "<html>"
-        "<body>"
-          "<font color=\"#c0c0c0\">"
-            "<h2>Fetching Package Definition ...</h2>"
-            "<p><b>URL</b>: %1</p>"
-          "</font>"
-        "</body>"
-      "</html>"
-    )
-    .arg (tl::to_qstring (SaltGrain::spec_url (g->url ())));
-
-    details->setHtml (html);
-
-    std::string url = g->url ();
-    m_downloaded_grain.reset (new SaltGrain ());
-    m_downloaded_grain->set_url (url);
+      if (g->url ().empty ()) {
+        throw tl::Exception (tl::to_string (tr ("No download link available")));
+      }
 
-    //  NOTE: stream_from_url may modify the URL, hence we set it again
-    m_downloaded_grain_reader.reset (SaltGrain::stream_from_url (url));
-    m_downloaded_grain->set_url (url);
+      QString html = tr (
+        "<html>"
+          "<body>"
+            "<font color=\"#c0c0c0\">"
+              "<h2>Fetching Package Definition ...</h2>"
+              "<p><b>URL</b>: %1</p>"
+              "<p>%2</p>"
+            "</font>"
+          "</body>"
+        "</html>"
+      )
+      .arg (tl::to_qstring (g->url ()));
+
+      details->setHtml (html.arg (QString ()));
+
+      FetchGrainInfoProgressAdaptor pa (details, g->name (), html);
+
+      std::string url = g->url ();
+
+      auto sg = m_salt_grain_cache.find (url);
+      if (sg == m_salt_grain_cache.end ()) {
+
+        m_downloaded_grain.reset (new SaltGrain ());
+        m_downloaded_grain->set_url (url);
+
+        //  NOTE: stream_from_url may modify the URL, hence we set it again
+        ProcessEventCallback callback;
+        m_downloaded_grain_reader.reset (SaltGrain::stream_from_url (url, 60.0, &callback));
+        m_downloaded_grain->set_url (url);
+
+        tl::InputHttpStream *http = dynamic_cast<tl::InputHttpStream *> (m_downloaded_grain_reader->base ());
+        if (http) {
+          //  async reading on HTTP
+          http->ready ().add (this, &SaltManagerDialog::data_ready);
+          http->send ();
+        } else {
+          data_ready ();
+        }
 
-    tl::InputHttpStream *http = dynamic_cast<tl::InputHttpStream *> (m_downloaded_grain_reader->base ());
-    if (http) {
-      //  async reading on HTTP
-      http->ready ().add (this, &SaltManagerDialog::data_ready);
-      http->send ();
-    } else {
-      data_ready ();
+      } else {
+
+        m_downloaded_grain.reset (new SaltGrain (sg->second));
+        data_ready ();
+
+      }
+
+    } catch (tl::Exception &ex) {
+      show_error (ex);
     }
 
-  } catch (tl::Exception &ex) {
-    show_error (ex);
+  } else {
+
+    //  Download denied - take information from index
+    m_downloaded_grain.reset (new SaltGrain (*g));
+    data_ready ();
+
   }
 }
 
 void
 SaltManagerDialog::data_ready ()
 {
-  if (! m_salt_mine_grain.get () || ! m_downloaded_grain.get () || ! m_downloaded_grain_reader.get () || ! mp_downloaded_target) {
+  if (! m_salt_mine_grain.get () || ! m_downloaded_grain.get () || ! mp_downloaded_target) {
     return;
   }
 
   //  Load the grain file (save URL as it is overwritten by the grain.xml content)
   std::string url = m_downloaded_grain->url ();
-  m_downloaded_grain->load (*m_downloaded_grain_reader);
-  m_downloaded_grain->set_url (url);
+  if (m_downloaded_grain_reader.get ()) {
+    m_downloaded_grain->load (*m_downloaded_grain_reader);
+    m_downloaded_grain->set_url (url);
+  }
+
+  //  commit to cache
+  if (m_salt_grain_cache.find (url) == m_salt_grain_cache.end ()) {
+    m_salt_grain_cache [url] = *m_downloaded_grain;
+  }
 
   try {
 
@@ -1223,6 +1336,7 @@ SaltManagerDialog::data_ready ()
     m_salt_mine_grain.reset (0);
 
   } catch (tl::Exception &ex) {
+    m_downloaded_grain.reset (0);
     show_error (ex);
   }
 }
diff --git a/src/lay/lay/laySaltManagerDialog.h b/src/lay/lay/laySaltManagerDialog.h
index a16662cd9a..dd899371b1 100644
--- a/src/lay/lay/laySaltManagerDialog.h
+++ b/src/lay/lay/laySaltManagerDialog.h
@@ -188,6 +188,9 @@ private slots:
   std::unique_ptr<lay::SaltGrain> m_downloaded_grain, m_salt_mine_grain;
   SaltGrainDetailsTextWidget *mp_downloaded_target;
   std::unique_ptr<tl::InputStream> m_salt_mine_reader;
+  tl::DeferredMethod<SaltManagerDialog> dm_mine_update_selected_changed;
+  tl::DeferredMethod<SaltManagerDialog> dm_mine_new_selected_changed;
+  std::map<std::string, lay::SaltGrain> m_salt_grain_cache;
 
   SaltGrain *current_grain ();
   std::vector<lay::SaltGrain *> current_grains ();
@@ -199,6 +202,8 @@ private slots:
   void show_error (tl::Exception &ex);
   void salt_mine_download_started ();
   void salt_mine_download_finished ();
+  void do_mine_update_selected_changed ();
+  void do_mine_new_selected_changed ();
 };
 
 }
diff --git a/src/lay/lay/laySaltParsedURL.cc b/src/lay/lay/laySaltParsedURL.cc
new file mode 100644
index 0000000000..84e2c0850f
--- /dev/null
+++ b/src/lay/lay/laySaltParsedURL.cc
@@ -0,0 +1,150 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2023 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#include "laySaltParsedURL.h"
+#include "laySaltGrain.h"
+#include "tlString.h"
+
+namespace lay
+{
+
+static void
+parse_git_url (tl::Extractor &ex, std::string &url, std::string &branch, std::string &subfolder)
+{
+  const char *org_str = ex.get ();
+
+  std::string w;
+  // protocol (http:)
+  ex.try_read_word (w, "") && ex.test (":");
+  while (! ex.at_end () && ex.test ("/")) {
+    ;
+  }
+  // server ("www.klayout.de")
+  while (! ex.at_end () && (*ex != '/' && *ex != '+' && *ex != '[')) {
+    ++ex;
+  }
+
+  while (! ex.at_end ()) {
+
+    ++ex;
+
+    //  next component
+    const char *c1 = ex.get ();
+    while (! ex.at_end () && (*ex != '/' && *ex != '+' && *ex != '[')) {
+      ++ex;
+    }
+    const char *c2 = ex.get ();
+
+    std::string comp (c1, c2 - c1);
+
+    if ((! ex.at_end () && (*ex == '+' || *ex == '[')) || comp.find (".git") == comp.size () - 4) {
+      //  subfolder starts here
+      break;
+    }
+
+  }
+
+  url = std::string (org_str, ex.get () - org_str);
+
+  if (ex.at_end ()) {
+    return;
+  }
+
+  //  skip URL/subfolder separator
+  if (*ex == '/') {
+    while (! ex.at_end () && *ex == '/') {
+      ++ex;
+    }
+  } else if (*ex == '+') {
+    ++ex;
+  }
+
+  //  subfolders
+  {
+    const char *c1 = ex.get ();
+    while (! ex.at_end () && *ex != '[') {
+      ++ex;
+    }
+    const char *c2 = ex.get ();
+    subfolder = std::string (c1, c2 - c1);
+  }
+
+  if (! ex.at_end () && *ex == '[') {
+
+    //  explicit branch
+    ++ex;
+    const char *c1 = ex.get ();
+    while (! ex.at_end () && *ex != ']') {
+      ++ex;
+    }
+    const char *c2 = ex.get ();
+    branch = std::string (c1, c2 - c1);
+
+  } else if (! subfolder.empty ()) {
+
+    //  SVN emulation
+
+    auto parts = tl::split (subfolder, "/");
+    if (parts.size () >= 1 && parts.front () == "trunk") {
+
+      branch = "HEAD";
+      parts.erase (parts.begin ());
+      subfolder = tl::join (parts, "/");
+
+    } else if (parts.size () >= 2 && parts.front () == "tags") {
+
+      branch = "refs/tags/" + parts[1];
+      parts.erase (parts.begin (), parts.begin () + 2);
+      subfolder = tl::join (parts, "/");
+
+    } else if (parts.size () >= 2 && parts.front () == "branches") {
+
+      branch = "refs/heads/" + parts[1];
+      parts.erase (parts.begin (), parts.begin () + 2);
+      subfolder = tl::join (parts, "/");
+
+    }
+
+  }
+}
+
+SaltParsedURL::SaltParsedURL (const std::string &url)
+  : m_protocol (lay::DefaultProtocol)
+{
+  tl::Extractor ex (url.c_str ());
+  if (ex.test ("svn") && ex.test ("+")) {
+    m_protocol = lay::WebDAV;
+    m_url = ex.get ();
+    return;
+  }
+
+  ex = tl::Extractor (url.c_str ());
+  if (ex.test ("git") && ex.test ("+")) {
+    m_protocol = lay::Git;
+    parse_git_url (ex, m_url, m_branch, m_subfolder);
+    return;
+  }
+
+  m_url = url;
+}
+
+}
diff --git a/src/lay/lay/laySaltParsedURL.h b/src/lay/lay/laySaltParsedURL.h
new file mode 100644
index 0000000000..fd41bb42d2
--- /dev/null
+++ b/src/lay/lay/laySaltParsedURL.h
@@ -0,0 +1,115 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2023 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#ifndef HDR_laySaltParsedURL
+#define HDR_laySaltParsedURL
+
+#include "layCommon.h"
+#include "laySaltGrain.h"
+
+namespace lay
+{
+
+/**
+ *  @brief An enum describing the protocol to use for download
+ */
+enum Protocol {
+  DefaultProtocol = 0,
+  WebDAV = 1,
+  Git = 2
+};
+
+/**
+ *  @brief A class representing a SaltGrain URL
+ *
+ *  The URL is parsed into protocol, branch, URL and subfolder if applicable.
+ *  Some heuristics is applied to decompose parts.
+ *
+ *  SVN URLs:
+ *    https://server.com/repo/trunk                               -> protocol=DefaultProtocol, url="https://server.com/repo/trunk", branch="", subfolder=""
+ *    svn+https://server.com/repo/trunk                           -> protocol=WebDAV, url="https://server.com/repo/trunk", branch="", subfolder=""
+ *
+ *  Git URL heuristics:
+ *    git+https://server.com/repo.git                             -> protocol=Git, url="https://server.com/repo.git", branch="", subfolder=""
+ *    git+https://server.com/repo.git/sub/folder                  -> protocol=Git, url="https://server.com/repo.git", branch="", subfolder="sub/folder"
+ *    git+https://server.com/repo+sub/folder                      -> protocol=Git, url="https://server.com/repo", branch="", subfolder="sub/folder"
+ *    git+https://server.com/repo.git[v1.0]                       -> protocol=Git, url="https://server.com/repo.git", branch="v1.0", subfolder=""
+ *    git+https://server.com/repo.git/sub/folder[refs/tags/1.0]   -> protocol=Git, url="https://server.com/repo.git", branch="refs/tags/1.0", subfolder="sub/folder"
+ *    git+https://server.com/repo.git/trunk                       -> protocol=Git, url="https://server.com/repo.git", branch="HEAD", subfolder=""
+ *    git+https://server.com/repo.git/trunk/sub/folder            -> protocol=Git, url="https://server.com/repo.git", branch="HEAD", subfolder="sub/folder"
+ *    git+https://server.com/repo.git/branches/release            -> protocol=Git, url="https://server.com/repo.git", branch="refs/heads/release", subfolder=""
+ *    git+https://server.com/repo.git/tags/1.9                    -> protocol=Git, url="https://server.com/repo.git", branch="refs/tags/1.9", subfolder=""
+ *    git+https://server.com/repo.git/tags/1.9/sub/folder         -> protocol=Git, url="https://server.com/repo.git", branch="refs/tags/1.9", subfolder="sub/folder"
+ */
+
+class LAY_PUBLIC SaltParsedURL
+{
+public:
+  /**
+   *  @brief Constructor: creates an URL from the given generic URL string
+   *
+   *  This will decompose the URL into the parts and fill protocol, branch and subfolder fields.
+   */
+  SaltParsedURL (const std::string &url);
+
+  /**
+   *  @brief Gets the basic URL
+   */
+  const std::string &url () const
+  {
+    return m_url;
+  }
+
+  /**
+   *  @brief Gets the subfolder string
+   */
+  const std::string &subfolder () const
+  {
+    return m_subfolder;
+  }
+
+  /**
+   *  @brief Gets the branch string
+   */
+  const std::string &branch () const
+  {
+    return m_branch;
+  }
+
+  /**
+   *  @brief Gets the protocol
+   */
+  lay::Protocol protocol () const
+  {
+    return m_protocol;
+  }
+
+private:
+  std::string m_url;
+  std::string m_branch;
+  std::string m_subfolder;
+  lay::Protocol m_protocol;
+};
+
+}
+
+#endif
diff --git a/src/lay/unit_tests/laySaltParsedURLTests.cc b/src/lay/unit_tests/laySaltParsedURLTests.cc
new file mode 100644
index 0000000000..b4274b3fdb
--- /dev/null
+++ b/src/lay/unit_tests/laySaltParsedURLTests.cc
@@ -0,0 +1,141 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2023 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#include "laySaltParsedURL.h"
+#include "tlUnitTest.h"
+
+TEST (1_Basic)
+{
+  lay::SaltParsedURL purl ("https://server.com/repo/trunk");
+  EXPECT_EQ (purl.protocol () == lay::DefaultProtocol, true);
+  EXPECT_EQ (purl.url (), "https://server.com/repo/trunk");
+  EXPECT_EQ (purl.branch (), "");
+  EXPECT_EQ (purl.subfolder (), "");
+}
+
+TEST (2_SVN)
+{
+  lay::SaltParsedURL purl ("svn+https://server.com/repo/trunk");
+  EXPECT_EQ (purl.protocol () == lay::WebDAV, true);
+  EXPECT_EQ (purl.url (), "https://server.com/repo/trunk");
+  EXPECT_EQ (purl.branch (), "");
+  EXPECT_EQ (purl.subfolder (), "");
+}
+
+TEST (10_GitBasic)
+{
+  lay::SaltParsedURL purl ("git+https://server.com/repo.git");
+  EXPECT_EQ (purl.protocol () == lay::Git, true);
+  EXPECT_EQ (purl.url (), "https://server.com/repo.git");
+  EXPECT_EQ (purl.branch (), "");
+  EXPECT_EQ (purl.subfolder (), "");
+}
+
+TEST (11_GitSubFolder)
+{
+  lay::SaltParsedURL purl ("git+https://server.com/repo.git/sub/folder");
+  EXPECT_EQ (purl.protocol () == lay::Git, true);
+  EXPECT_EQ (purl.url (), "https://server.com/repo.git");
+  EXPECT_EQ (purl.branch (), "");
+  EXPECT_EQ (purl.subfolder (), "sub/folder");
+}
+
+TEST (12_GitExplicitBranch)
+{
+  lay::SaltParsedURL purl ("git+https://server.com/repo.git[v1.0]");
+  EXPECT_EQ (purl.protocol () == lay::Git, true);
+  EXPECT_EQ (purl.url (), "https://server.com/repo.git");
+  EXPECT_EQ (purl.branch (), "v1.0");
+  EXPECT_EQ (purl.subfolder (), "");
+}
+
+TEST (13_GitExplicitBranchAndSubFolder)
+{
+  lay::SaltParsedURL purl ("git+https://server.com/repo.git/sub/folder[refs/tags/1.0]");
+  EXPECT_EQ (purl.protocol () == lay::Git, true);
+  EXPECT_EQ (purl.url (), "https://server.com/repo.git");
+  EXPECT_EQ (purl.branch (), "refs/tags/1.0");
+  EXPECT_EQ (purl.subfolder (), "sub/folder");
+}
+
+TEST (14_GitExplicitBranchAndExplicitSubFolder)
+{
+  lay::SaltParsedURL purl ("git+https://server.com/repo+sub/folder[refs/tags/1.0]");
+  EXPECT_EQ (purl.protocol () == lay::Git, true);
+  EXPECT_EQ (purl.url (), "https://server.com/repo");
+  EXPECT_EQ (purl.branch (), "refs/tags/1.0");
+  EXPECT_EQ (purl.subfolder (), "sub/folder");
+}
+
+TEST (15_GitSVNEmulationTrunk)
+{
+  lay::SaltParsedURL purl ("git+https://server.com/repo.git/trunk");
+  EXPECT_EQ (purl.protocol () == lay::Git, true);
+  EXPECT_EQ (purl.url (), "https://server.com/repo.git");
+  EXPECT_EQ (purl.branch (), "HEAD");
+  EXPECT_EQ (purl.subfolder (), "");
+}
+
+TEST (16_GitSVNEmulationTrunkWithSubFolder)
+{
+  lay::SaltParsedURL purl ("git+https://server.com/repo.git/trunk/sub/folder");
+  EXPECT_EQ (purl.protocol () == lay::Git, true);
+  EXPECT_EQ (purl.url (), "https://server.com/repo.git");
+  EXPECT_EQ (purl.branch (), "HEAD");
+  EXPECT_EQ (purl.subfolder (), "sub/folder");
+}
+
+TEST (17_GitSVNEmulationBranch)
+{
+  lay::SaltParsedURL purl ("git+https://server.com/repo.git/branches/xyz");
+  EXPECT_EQ (purl.protocol () == lay::Git, true);
+  EXPECT_EQ (purl.url (), "https://server.com/repo.git");
+  EXPECT_EQ (purl.branch (), "refs/heads/xyz");
+  EXPECT_EQ (purl.subfolder (), "");
+}
+
+TEST (18_GitSVNEmulationTag)
+{
+  lay::SaltParsedURL purl ("git+https://server.com/repo.git/tags/1.9");
+  EXPECT_EQ (purl.protocol () == lay::Git, true);
+  EXPECT_EQ (purl.url (), "https://server.com/repo.git");
+  EXPECT_EQ (purl.branch (), "refs/tags/1.9");
+  EXPECT_EQ (purl.subfolder (), "");
+}
+
+TEST (19_GitSVNEmulationTagWithSubFolder)
+{
+  lay::SaltParsedURL purl ("git+https://server.com/repo.git/tags/1.9/sub/folder");
+  EXPECT_EQ (purl.protocol () == lay::Git, true);
+  EXPECT_EQ (purl.url (), "https://server.com/repo.git");
+  EXPECT_EQ (purl.branch (), "refs/tags/1.9");
+  EXPECT_EQ (purl.subfolder (), "sub/folder");
+}
+
+TEST (20_Example1)
+{
+  lay::SaltParsedURL purl ("git+https://github.com/my-user/test-core[refs/tags/v1.1.0]");
+  EXPECT_EQ (purl.protocol () == lay::Git, true);
+  EXPECT_EQ (purl.url (), "https://github.com/my-user/test-core");
+  EXPECT_EQ (purl.branch (), "refs/tags/v1.1.0");
+  EXPECT_EQ (purl.subfolder (), "");
+}
diff --git a/src/lay/unit_tests/unit_tests.pro b/src/lay/unit_tests/unit_tests.pro
index bd437bdbbd..adf9559669 100644
--- a/src/lay/unit_tests/unit_tests.pro
+++ b/src/lay/unit_tests/unit_tests.pro
@@ -9,6 +9,7 @@ include($$PWD/../../lib_ut.pri)
 SOURCES = \
   laySalt.cc \
   layHelpIndexTest.cc \
+  laySaltParsedURLTests.cc \
   laySessionTests.cc
 
 INCLUDEPATH += $$LAY_INC $$TL_INC $$LAYBASIC_INC $$LAYUI_INC $$LAYVIEW_INC $$DB_INC $$GSI_INC $$ANT_INC $$IMG_INC $$RDB_INC
diff --git a/src/lib/lib/lib.pro b/src/lib/lib/lib.pro
index 8352f19af0..98f84bd541 100644
--- a/src/lib/lib/lib.pro
+++ b/src/lib/lib/lib.pro
@@ -1,40 +1,42 @@
-
-DESTDIR = $$OUT_PWD/../..
-TARGET = klayout_lib
-
-include($$PWD/../../lib.pri)
-
-DEFINES += MAKE_LIB_LIBRARY
-
-HEADERS = \
-  libBasicArc.h \
-  libBasicCircle.h \
-  libBasicDonut.h \
-  libBasicEllipse.h \
-  libBasicPie.h \
-  libBasicRoundPath.h \
-  libBasicRoundPolygon.h \
-  libBasicStrokedPolygon.h \
-  libBasicText.h \
-  libForceLink.h
-
-SOURCES = \
-  libForceLink.cc \
-  libBasic.cc \
-  libBasicArc.cc \
-  libBasicCircle.cc \
-  libBasicDonut.cc \
-  libBasicEllipse.cc \
-  libBasicPie.cc \
-  libBasicRoundPath.cc \
-  libBasicRoundPolygon.cc \
-  libBasicStrokedPolygon.cc \
-  libBasicText.cc
-
-RESOURCES = \
-  libResources.qrc
-
-INCLUDEPATH += $$TL_INC $$GSI_INC $$DB_INC
-DEPENDPATH += $$TL_INC $$GSI_INC $$DB_INC
-LIBS += -L$$DESTDIR -lklayout_gsi -lklayout_tl -lklayout_db
-
+
+DESTDIR = $$OUT_PWD/../..
+TARGET = klayout_lib
+
+include($$PWD/../../lib.pri)
+
+DEFINES += MAKE_LIB_LIBRARY
+
+HEADERS = \
+  libBasicArc.h \
+  libBasicCircle.h \
+  libBasicDonut.h \
+  libBasicEllipse.h \
+  libBasicPie.h \
+  libBasicRoundPath.h \
+  libBasicRoundPolygon.h \
+  libBasicStrokedPolygon.h \
+  libBasicText.h \
+  libForceLink.h
+
+SOURCES = \
+  libForceLink.cc \
+  libBasic.cc \
+  libBasicArc.cc \
+  libBasicCircle.cc \
+  libBasicDonut.cc \
+  libBasicEllipse.cc \
+  libBasicPie.cc \
+  libBasicRoundPath.cc \
+  libBasicRoundPolygon.cc \
+  libBasicStrokedPolygon.cc \
+  libBasicText.cc
+
+!equals(HAVE_QT, "0") {
+  RESOURCES = \
+    libResources.qrc
+}
+
+INCLUDEPATH += $$TL_INC $$GSI_INC $$DB_INC
+DEPENDPATH += $$TL_INC $$GSI_INC $$DB_INC
+LIBS += -L$$DESTDIR -lklayout_gsi -lklayout_tl -lklayout_db
+
diff --git a/src/lvs/lvs/lvs.pro b/src/lvs/lvs/lvs.pro
index 5a8c53f27f..722270f843 100644
--- a/src/lvs/lvs/lvs.pro
+++ b/src/lvs/lvs/lvs.pro
@@ -13,7 +13,7 @@ HEADERS = \
   lvsCommon.h \
   lvsForceLink.h \
 
-!equals(HAVE_QT, "0") || !equals(HAVE_PYTHON, "0") {
+!equals(HAVE_QT, "0") {
   RESOURCES = \
     lvsResources.qrc
 }
diff --git a/src/rba/unit_tests/unit_tests.pro b/src/rba/unit_tests/unit_tests.pro
index 6bca18f2fd..5924ccae6b 100644
--- a/src/rba/unit_tests/unit_tests.pro
+++ b/src/rba/unit_tests/unit_tests.pro
@@ -14,7 +14,7 @@ DEPENDPATH += $$RBA_INC $$TL_INC $$DB_INC $$GSI_INC
 
 LIBS += -L$$DESTDIR_UT -lklayout_rba -lklayout_tl -lklayout_db -lklayout_gsi
 
-!equals(HAVE_QT, "0") || !equals(HAVE_PYTHON, "0") {
+!equals(HAVE_QT, "0") {
   RESOURCES = \
     rba_unit_tests.qrc
 }
diff --git a/src/tl/tl/tl.pro b/src/tl/tl/tl.pro
index 558134601b..5a9f735622 100644
--- a/src/tl/tl/tl.pro
+++ b/src/tl/tl/tl.pro
@@ -121,7 +121,17 @@ HEADERS = \
     tlUniqueName.h \
     tlRecipe.h \
     tlSelect.h \
-    tlEnv.h
+    tlEnv.h 
+
+equals(HAVE_GIT2, "1") {
+
+  HEADERS += \
+    tlGit.h
+
+  SOURCES += \
+    tlGit.cc
+
+}
 
 equals(HAVE_CURL, "1") {
 
diff --git a/src/tl/tl/tlFileSystemWatcher.h b/src/tl/tl/tlFileSystemWatcher.h
index f6190f2086..d7435c2615 100644
--- a/src/tl/tl/tlFileSystemWatcher.h
+++ b/src/tl/tl/tlFileSystemWatcher.h
@@ -140,6 +140,23 @@ private slots:
   std::map<std::string, FileEntry>::iterator m_iter;
 };
 
+/**
+ *  @brief A class employing RIIA for locking the file system watcher
+ */
+class TL_PUBLIC FileSystemWatcherDisabled
+{
+public:
+  FileSystemWatcherDisabled ()
+  {
+    tl::FileSystemWatcher::global_enable (false);
+  }
+
+  ~FileSystemWatcherDisabled ()
+  {
+    tl::FileSystemWatcher::global_enable (true);
+  }
+};
+
 }
 
 #endif
diff --git a/src/tl/tl/tlFileUtils.cc b/src/tl/tl/tlFileUtils.cc
index e575dbb634..28c3741a39 100644
--- a/src/tl/tl/tlFileUtils.cc
+++ b/src/tl/tl/tlFileUtils.cc
@@ -27,6 +27,7 @@
 #include "tlEnv.h"
 
 #include <cctype>
+#include <fstream>
 
 // Use this define to print debug output
 // #define FILE_UTILS_VERBOSE
@@ -584,6 +585,48 @@ cp_dir_recursive (const std::string &source, const std::string &target)
   return true;
 }
 
+bool
+mv_dir_recursive (const std::string &source, const std::string &target)
+{
+  std::vector<std::string> entries;
+  std::string path = tl::absolute_file_path (source);
+  std::string path_to = tl::absolute_file_path (target);
+
+  bool error = false;
+
+  entries = dir_entries (path, false /*without_files*/, true /*with_dirs*/);
+  for (std::vector<std::string>::const_iterator e = entries.begin (); e != entries.end (); ++e) {
+    std::string tc = tl::combine_path (path_to, *e);
+    if (! mkpath (tc)) {
+#if defined(FILE_UTILS_VERBOSE)
+      tl::error << tr ("Unable to create target directory: ") << tc;
+#endif
+      error = true;
+    } else if (! mv_dir_recursive (tl::combine_path (path, *e), tc)) {
+      error = true;
+    }
+  }
+
+  entries = dir_entries (path, true /*with_files*/, false /*without_dirs*/);
+  for (std::vector<std::string>::const_iterator e = entries.begin (); e != entries.end (); ++e) {
+    if (! tl::rename_file (tl::combine_path (path, *e), tl::combine_path (path_to, *e))) {
+#if defined(FILE_UTILS_VERBOSE)
+      tl::error << tr ("Unable to move file from ") << tl::combine_path (path, *e) << tr (" to ") << tl::combine_path (path_to, *e);
+#endif
+      error = true;
+    }
+  }
+
+  if (! tl::rm_dir (path)) {
+#if defined(FILE_UTILS_VERBOSE)
+      tl::error << tr ("Unable to remove folder ") << path;
+#endif
+    error = true;
+  }
+
+  return ! error;
+}
+
 std::string absolute_path (const std::string &s)
 {
   std::vector<std::string> parts = split_path (absolute_file_path (s));
@@ -976,4 +1019,108 @@ get_module_path (void *addr)
 #endif
 }
 
+std::string
+tmpfile (const std::string &domain)
+{
+  std::string tmp = tl::get_env ("TMPDIR");
+  if (tmp.empty ()) {
+    tmp = tl::get_env ("TMP");
+  }
+  if (tmp.empty ()) {
+#if defined(_WIN32)
+    throw tl::Exception (tl::to_string (tr ("TMP and TMPDIR not set - cannot create temporary file")));
+#else
+    tmp = "/tmp";
+#endif
+  }
+
+  std::string templ = tl::combine_path (tmp, domain + "XXXXXX");
+  char *tmpstr = strdup (templ.c_str ());
+
+#if defined(_WIN32)
+  if (_mktemp_s (tmpstr, templ.size () + 1) != 0) {
+    free (tmpstr);
+    throw tl::Exception (tl::to_string (tr ("Unable to create temporary folder name in %s")), tmp);
+  }
+
+  //  for compatibility with Linux, create the file as an empty one
+  std::ofstream os (tmpstr);
+  if (os.bad ()) {
+    throw tl::Exception (tl::to_string (tr ("Unable to create temporary folder in %s")), tmp);
+  }
+  os.close ();
+#else
+  int fd = mkstemp (tmpstr);
+  if (fd < 0) {
+    free (tmpstr);
+    throw tl::Exception (tl::to_string (tr ("Unable to create temporary folder in %s")), tmp);
+  }
+  close (fd);
+#endif
+
+  std::string res = tmpstr;
+  free (tmpstr);
+  return res;
+}
+
+TemporaryFile::TemporaryFile (const std::string &domain)
+{
+  m_path = tmpfile (domain);
+}
+
+TemporaryFile::~TemporaryFile ()
+{
+  tl::rm_file (m_path);
+}
+
+std::string
+tmpdir (const std::string &domain)
+{
+  std::string tmp = tl::get_env ("TMPDIR");
+  if (tmp.empty ()) {
+    tmp = tl::get_env ("TMP");
+  }
+  if (tmp.empty ()) {
+#if defined(_WIN32)
+    throw tl::Exception (tl::to_string (tr ("TMP and TMPDIR not set - cannot create temporary file")));
+#else
+    tmp = "/tmp";
+#endif
+  }
+
+  std::string templ = tl::combine_path (tmp, domain + "XXXXXX");
+  char *tmpstr = strdup (templ.c_str ());
+
+#if defined(_WIN32)
+  if (_mktemp_s (tmpstr, templ.size () + 1) != 0) {
+    free (tmpstr);
+    throw tl::Exception (tl::to_string (tr ("Unable to create temporary folder name in %s")), tmp);
+  }
+  if (! tl::mkdir (tmpstr)) {
+    free (tmpstr);
+    throw tl::Exception (tl::to_string (tr ("Unable to create temporary folder in %s")), tmp);
+  }
+#else
+  if (mkdtemp (tmpstr) == NULL) {
+    free (tmpstr);
+    throw tl::Exception (tl::to_string (tr ("Unable to create temporary folder in %s")), tmp);
+  }
+#endif
+
+  std::string res = tmpstr;
+  free (tmpstr);
+  return res;
+}
+
+TemporaryDirectory::TemporaryDirectory (const std::string &domain)
+{
+  m_path = tmpdir (domain);
+}
+
+TemporaryDirectory::~TemporaryDirectory ()
+{
+  tl::rm_dir_recursive (m_path);
+}
+
+
 }
diff --git a/src/tl/tl/tlFileUtils.h b/src/tl/tl/tlFileUtils.h
index f192599ff5..474ec7e29d 100644
--- a/src/tl/tl/tlFileUtils.h
+++ b/src/tl/tl/tlFileUtils.h
@@ -52,11 +52,18 @@ bool TL_PUBLIC rm_dir_recursive (const std::string &path);
 bool TL_PUBLIC mkpath (const std::string &path);
 
 /**
- *  @brief Recursively remove the given directory, the files from that directory and all sub-directories (version with std::string)
+ *  @brief Recursively copy the given directory
  *  @return True, if successful. false otherwise.
  */
 bool TL_PUBLIC cp_dir_recursive (const std::string &source, const std::string &target);
 
+/**
+ *  @brief Recursively move the contents of the given directory
+ *  @return True, if successful. false otherwise.
+ *  After this operation, the source directory is deleted.
+ */
+bool TL_PUBLIC mv_dir_recursive (const std::string &source, const std::string &target);
+
 /**
  *  @brief Gets the absolute path for a given file path
  *  This will deliver the directory of the file as absolute path.
@@ -181,6 +188,68 @@ std::string TL_PUBLIC current_dir ();
  */
 bool TL_PUBLIC chdir (const std::string &path);
 
+/**
+ *  @brief Gets a temporary file path
+ *
+ *  This function will make a temporary file with a unique name.
+ *  The "domain" string is used as part of the file name as an disambiguator.
+ *
+ *  The function reads $TMPDIR or $TMP to define the location of the temporary
+ *  directory. On Linux, the default is /tmp.
+ *
+ *  The file is created and it is the responsibility of the caller to remove
+ *  the file.
+ */
+std::string TL_PUBLIC tmpfile (const std::string &domain = std::string ());
+
+/**
+ *  @brief A class wrapping a temporary file
+ *
+ *  In the destructor of this class, the temporary file will be deleted again.
+ */
+class TL_PUBLIC TemporaryFile
+{
+public:
+  TemporaryFile (const std::string &domain = std::string ());
+  ~TemporaryFile ();
+
+  const std::string &path () const
+  {
+    return m_path;
+  }
+
+private:
+  std::string m_path;
+};
+
+/**
+ *  @brief Gets a temporary folder path
+ *
+ *  Similar to "tmpfile", but will create a new, empty folder. Again it is the
+ *  reposibility of the caller to clean up.
+ */
+std::string TL_PUBLIC tmpdir (const std::string &domain = std::string ());
+
+/**
+ *  @brief A class wrapping a temporary directory
+ *
+ *  In the destructor of this class, the temporary directory will be deleted again.
+ */
+class TL_PUBLIC TemporaryDirectory
+{
+public:
+  TemporaryDirectory (const std::string &domain = std::string ());
+  ~TemporaryDirectory ();
+
+  const std::string &path () const
+  {
+    return m_path;
+  }
+
+private:
+  std::string m_path;
+};
+
 /**
  *  @brief This function splits the path into it's components
  *  On Windows, the first component may be the drive prefix ("C:") or
diff --git a/src/tl/tl/tlGit.cc b/src/tl/tl/tlGit.cc
new file mode 100644
index 0000000000..6810b07ea6
--- /dev/null
+++ b/src/tl/tl/tlGit.cc
@@ -0,0 +1,421 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2023 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#if defined(HAVE_GIT2)
+
+#include "tlGit.h"
+#include "tlFileUtils.h"
+#include "tlProgress.h"
+#include "tlStaticObjects.h"
+#include "tlLog.h"
+
+#include <git2.h>
+#include <cstdio>
+
+namespace tl
+{
+
+// ---------------------------------------------------------------
+//  Library initialization helper
+
+namespace {
+
+class InitHelper
+{
+public:
+  InitHelper ()
+  {
+    git_libgit2_init ();
+  }
+
+  ~InitHelper ()
+  {
+    git_libgit2_shutdown ();
+  }
+
+  static void ensure_initialized ()
+  {
+    if (ms_init) {
+      return;
+    }
+
+    ms_init = new InitHelper ();
+    tl::StaticObjects::reg (&ms_init);
+  }
+
+private:
+  static InitHelper *ms_init;
+};
+
+InitHelper *InitHelper::ms_init = 0;
+
+}
+
+// ---------------------------------------------------------------
+//  GitCollection implementation
+
+GitObject::GitObject (const std::string &local_path)
+  : m_local_path (local_path), m_is_temp (false)
+{
+  InitHelper::ensure_initialized ();
+
+  if (local_path.empty ()) {
+    m_local_path = tl::tmpdir ("git2klayout");
+    m_is_temp = true;
+  }
+
+  //  ensures the directory is clean
+  if (! m_is_temp) {
+    if (! tl::rm_dir_recursive (m_local_path)) {
+      throw tl::Exception (tl::to_string (tr ("Unable to clean local Git repo path: %s")), m_local_path);
+    }
+    if (! tl::mkpath (m_local_path)) {
+      throw tl::Exception (tl::to_string (tr ("Unable to regenerate local Git repo path: %s")), m_local_path);
+    }
+  }
+}
+
+GitObject::~GitObject ()
+{
+  if (m_is_temp) {
+    tl::rm_dir_recursive (m_local_path);
+  }
+}
+
+static int
+#if LIBGIT2_VER_MAJOR >= 1
+fetch_progress (const git_indexer_progress *stats, void *payload)
+#else
+fetch_progress (const git_transfer_progress *stats, void *payload)
+#endif
+{
+  tl::RelativeProgress *progress = reinterpret_cast<tl::RelativeProgress *> (payload);
+
+  //  first half of progress
+  size_t count = size_t (5000.0 * double (stats->received_objects) / double (std::max (1u, stats->total_objects)) + 1e-10);
+  try {
+    progress->set (count);
+  } catch (...) {
+    //  TODO: stop
+  }
+
+  return 0;
+}
+
+static void
+checkout_progress(const char * /*path*/, size_t cur, size_t tot, void *payload)
+{
+  tl::RelativeProgress *progress = reinterpret_cast<tl::RelativeProgress *> (payload);
+
+  //  first half of progress
+  size_t count = size_t (5000.0 * double (cur) / double (std::max (size_t (1), tot)) + 1e-10);
+  try {
+    progress->set (count + 5000u);
+  } catch (...) {
+    //  ignore cancel requests (TODO: how to stop?)
+  }
+}
+
+static void check (int error)
+{
+  if (error != 0) {
+#if LIBGIT2_VER_MAJOR > 0 || (LIBGIT2_VER_MAJOR == 0 && LIBGIT2_VER_MINOR >= 28)
+    const git_error *err = git_error_last ();
+#else
+    const git_error *err = giterr_last ();
+#endif
+    throw tl::Exception (tl::to_string (tr ("Error cloning Git repo: %s")), (const char *) err->message);
+  }
+}
+
+static bool
+ref_matches (const char *name, const std::string &ref)
+{
+  if (!name) {
+    return false;
+  } else if (name == ref) {
+    return true;
+  } else if (name == "refs/heads/" + ref) {
+    return true;
+  } else if (name == "refs/tags/" + ref) {
+    return true;
+  } else {
+    return false;
+  }
+}
+
+namespace
+{
+
+class GitBuffer
+{
+public:
+  GitBuffer ()
+  {
+    m_buf = GIT_BUF_INIT_CONST (NULL, 0);
+  }
+
+  ~GitBuffer ()
+  {
+#if LIBGIT2_VER_MAJOR > 0 || (LIBGIT2_VER_MAJOR == 0 && LIBGIT2_VER_MINOR >= 28)
+    git_buf_dispose (&m_buf);
+#else
+    git_buf_free (&m_buf);
+#endif
+  }
+
+  const char *c_str () const { return m_buf.ptr; }
+
+  git_buf *get () { return &m_buf; }
+  const git_buf *get () const { return &m_buf; }
+
+private:
+  git_buf m_buf;
+};
+
+}
+
+static void
+checkout_branch (git_repository *repo, git_remote *remote, const git_checkout_options *co_opts, const char *branch)
+{
+  GitBuffer remote_branch;
+  git_oid oid;
+
+  //  if no branch is given, use the default branch
+  if (! branch) {
+    check (git_remote_default_branch (remote_branch.get (), remote));
+    branch = remote_branch.c_str ();
+    if (tl::verbosity () >= 10) {
+      tl::info << tr ("Git checkout: Using default branch for repository ") << git_remote_url (remote) << ": " << branch;
+    }
+  } else {
+    if (tl::verbosity () >= 10) {
+      tl::info << tr ("Git checkout: Checking out branch for repository ") << git_remote_url (remote) << ": " << branch;
+    }
+  }
+
+  //  resolve the branch by using ls-remote:
+
+  size_t n = 0;
+  const git_remote_head **ls = NULL;
+  check (git_remote_ls (&ls, &n, remote));
+
+  if (tl::verbosity () >= 20) {
+    tl::info << "Git checkout: ls-remote on " << git_remote_url (remote) << ":";
+  }
+
+  bool found = false;
+
+  for (size_t i = 0; i < n; ++i) {
+    const git_remote_head *rh = ls[i];
+    if (tl::verbosity () >= 20) {
+      char oid_fmt [80];
+      git_oid_tostr (oid_fmt, sizeof (oid_fmt), &rh->oid);
+      tl::info << "  " << rh->name << ": " << (const char *) oid_fmt;
+    }
+    if (ref_matches (rh->name, branch)) {
+      oid = rh->oid;
+      found = true;
+    }
+  }
+
+  if (! found) {
+    throw tl::Exception (tl::to_string (tr ("Git checkout - Unable to resolve reference name: ")) + branch);
+  }
+
+  if (tl::verbosity () >= 10) {
+    char oid_fmt [80];
+    git_oid_tostr (oid_fmt, sizeof (oid_fmt), &oid);
+    tl::info << tr ("Git checkout: resolving ") << branch << tr (" to ") << (const char *) oid_fmt;
+  }
+
+  check (git_repository_set_head_detached (repo, &oid));
+  check (git_checkout_head (repo, co_opts));
+}
+
+int
+credentials_cb (git_credential ** /*out*/, const char * /*url*/, const char * /*username*/, unsigned int /*allowed_types*/, void *)
+{
+  //  no credentials aquired
+  git_error_set_str (GIT_ERROR_NONE, "anonymous access is supported only, but server requests credentials");
+  return GIT_EUSER;
+}
+
+void
+GitObject::read (const std::string &org_url, const std::string &org_filter, const std::string &subfolder, const std::string &branch, double timeout, tl::InputHttpStreamCallback *callback)
+{
+  std::string url = org_url;
+
+  std::string filter = org_filter;
+  if (! subfolder.empty ()) {
+    if (filter.empty ()) {
+      filter = subfolder + "/**";
+    } else {
+      filter = subfolder + "/" + filter;
+    }
+  }
+
+  //  TODO: use callback, timeout?
+  tl::RelativeProgress progress (tl::to_string (tr ("Download progress")), 10000, 1 /*yield always*/);
+
+  //  build checkout options
+
+  git_checkout_options checkout_opts = GIT_CHECKOUT_OPTIONS_INIT;
+  checkout_opts.checkout_strategy = GIT_CHECKOUT_FORCE;
+
+  const char *paths_cstr[1];
+  paths_cstr[0] = filter.c_str ();
+  if (! filter.empty ()) {
+    checkout_opts.paths.count = 1;
+    checkout_opts.paths.strings = (char **) &paths_cstr;
+  }
+
+  checkout_opts.progress_cb = &checkout_progress;
+  checkout_opts.progress_payload = (void *) &progress;
+
+  //  build fetch options
+
+  git_fetch_options fetch_opts = GIT_FETCH_OPTIONS_INIT;
+
+  fetch_opts.download_tags = GIT_REMOTE_DOWNLOAD_TAGS_AUTO;
+
+#if LIBGIT2_VER_MAJOR > 1 || (LIBGIT2_VER_MAJOR == 1 && LIBGIT2_VER_MINOR >= 7)
+  fetch_opts.depth = 1;  // shallow (single commit)
+#endif
+  fetch_opts.callbacks.transfer_progress = &fetch_progress;
+  fetch_opts.callbacks.credentials = &credentials_cb;
+  fetch_opts.callbacks.payload = (void *) &progress;
+
+  //  build refspecs in case they are needed
+
+  char *refs[] = { (char *) branch.c_str () };
+  git_strarray refspecs;
+  refspecs.count = 1;
+  refspecs.strings = refs;
+  git_strarray *refspecs_p = branch.empty () ? NULL : &refspecs;
+
+  //  Make repository
+
+  git_repository *cloned_repo = NULL;
+  git_remote *remote = NULL;
+
+  try {
+
+    check (git_repository_init (&cloned_repo, m_local_path.c_str (), 0));
+
+    check (git_remote_create (&remote, cloned_repo, "download", url.c_str ()));
+
+    //  actually fetch
+    if (tl::verbosity () >= 10) {
+      tl::info << tr ("Fetching Git repo from ") << git_remote_url (remote) << " ...";
+    }
+    check (git_remote_fetch (remote, refspecs_p, &fetch_opts, NULL));
+
+    //  checkout
+    checkout_branch (cloned_repo, remote, &checkout_opts, branch.empty () ? 0 : branch.c_str ());
+
+    //  free the repo and remote
+    git_repository_free (cloned_repo);
+    git_remote_free (remote);
+
+    //  get rid of ".git" - we do not need it anymore
+
+    tl::rm_dir_recursive (tl::combine_path (m_local_path, ".git"));
+
+  } catch (...) {
+    //  free the repo in the error case
+    if (cloned_repo != NULL) {
+      git_repository_free (cloned_repo);
+    }
+    if (remote != NULL) {
+      git_remote_free (remote);
+    }
+    throw;
+  }
+
+  //  pull subfolder files to target path level
+  if (! subfolder.empty ()) {
+
+    std::string pp = tl::combine_path (m_local_path, subfolder);
+    if (! tl::is_dir (pp)) {
+      throw tl::Exception (tl::to_string (tr ("Error cloning Git repo - failed to fetch subdirectory: ")) + pp);
+    }
+
+    //  rename the source to a temporary folder so we don't overwrite the source folder with something from within
+    std::string tmp_dir = "__temp__";
+    for (unsigned int i = 0; ; ++i) {
+      if (! tl::file_exists (tl::combine_path (m_local_path, tmp_dir + tl::to_string (i)))) {
+        tmp_dir += tl::to_string (i);
+        break;
+      }
+    }
+    auto pc = tl::split (subfolder, "/");
+    if (! tl::rename_file (tl::combine_path (m_local_path, pc.front ()), tmp_dir)) {
+      throw tl::Exception (tl::to_string (tr ("Error cloning Git repo - failed to rename temp folder")));
+    }
+    pc.front () = tmp_dir;
+
+    if (! tl::mv_dir_recursive (tl::combine_path (m_local_path, tl::join (pc, "/")), m_local_path)) {
+      throw tl::Exception (tl::to_string (tr ("Error cloning Git repo - failed to move subdir components")));
+    }
+
+  }
+}
+
+bool
+GitObject::download (const std::string &url, const std::string &target, const std::string &subfolder, const std::string &branch, double timeout, tl::InputHttpStreamCallback *callback)
+{
+  try {
+
+    GitObject obj (target);
+    obj.read (url, std::string (), subfolder, branch, timeout, callback);
+
+    return true;
+
+  } catch (tl::Exception &ex) {
+
+    tl::error << tl::sprintf (tl::to_string (tr ("Error downloading Git repo from %s (subdir '%s', ref '%s')")), url, subfolder, branch);
+
+    return false;
+
+  }
+}
+
+tl::InputStream *
+GitObject::download_item (const std::string &url, const std::string &file, const std::string &subfolder, const std::string &branch, double timeout, tl::InputHttpStreamCallback *callback)
+{
+  GitObject obj;
+  obj.read (url, file, subfolder, branch, timeout, callback);
+
+  //  extract the file and return a memory blob, so we can delete the temp folder
+
+  tl::InputStream file_stream (tl::combine_path (obj.local_path (), file));
+  std::string data = file_stream.read_all ();
+
+  char *data_copy = new char [data.size ()];
+  memcpy (data_copy, data.c_str (), data.size ());
+  return new tl::InputStream (new tl::InputMemoryStream (data_copy, data.size (), true));
+}
+
+}
+
+#endif
diff --git a/src/tl/tl/tlGit.h b/src/tl/tl/tlGit.h
new file mode 100644
index 0000000000..a99d304499
--- /dev/null
+++ b/src/tl/tl/tlGit.h
@@ -0,0 +1,111 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2023 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+
+#ifndef HDR_tlGit
+#define HDR_tlGit
+
+#include "tlCommon.h"
+#include "tlStream.h"
+
+#include <string>
+#include <vector>
+
+#if !defined(HAVE_GIT2)
+#  error "tlGit.h can only be used with libgit2 enabled"
+#endif
+
+namespace tl
+{
+
+class InputHttpStreamCallback;
+
+/**
+ *  @brief Represents an object from a Git URL
+ *  This object can be a file or collection
+ */
+class TL_PUBLIC GitObject
+{
+public:
+  /**
+   *  @brief Open a stream with the given URL
+   *
+   *  The local_path is the path where to store the files.
+   *  If empty, a temporary folder is created and destroyed once the "GitObject" goes out of scope.
+   */
+  GitObject (const std::string &local_path = std::string ());
+
+  /**
+   *  @brief Destructor
+   */
+  ~GitObject ();
+
+  /**
+   *  @brief Populates the collection from the given URL
+   *
+   *  "filter" can be a top-level file to download. If filter is non-empty,
+   *  sparse mode is chosen.
+   */
+  void read (const std::string &url, const std::string &filter, const std::string &subfolder, const std::string &branch, double timeout = 60.0, tl::InputHttpStreamCallback *callback = 0);
+
+  /**
+   *  @brief Downloads the collection or file with the given URL
+   *
+   *  This method will download the Git object from url to the file path
+   *  given in "target".
+   *
+   *  For file download, the target must be the path of the target file.
+   *  For collection download, the target must be a directory path. In this
+   *  case, the target directory must exist already.
+   *
+   *  Sub-directories are created if required.
+   *
+   *  This method returns false if the directory structure could
+   *  not be obtained or downloading of one file failed.
+   *
+   *  "branch" is the remote ref to use. This can be a branch name, a tag name,
+   *  a remote ref such as "refs/heads/master" or a symbolic name such as "HEAD".
+   */
+  static bool download (const std::string &url, const std::string &target, const std::string &subfolder, const std::string &branch, double timeout = 60.0, tl::InputHttpStreamCallback *callback = 0);
+
+  /**
+   *  @brief Gets a stream object for downloading the single item of the given URL
+   *
+   *  The file needs to be a top-level object.
+   *  The stream object returned needs to be deleted by the caller.
+   */
+  static tl::InputStream *download_item (const std::string &url, const std::string &file, const std::string &subfolder, const std::string &branch, double timeout = 60.0, tl::InputHttpStreamCallback *callback = 0);
+
+private:
+  std::string m_local_path;
+  bool m_is_temp;
+
+  const std::string &local_path () const
+  {
+    return m_local_path;
+  }
+};
+
+}
+
+#endif
+
diff --git a/src/tl/tl/tlWebDAV.h b/src/tl/tl/tlWebDAV.h
index 5b676a2a7c..7a63f6a367 100644
--- a/src/tl/tl/tlWebDAV.h
+++ b/src/tl/tl/tlWebDAV.h
@@ -145,7 +145,7 @@ class TL_PUBLIC WebDAVObject
    *
    *  Sub-directories are created if required.
    *
-   *  This method throws an exception if the directory structure could
+   *  This method returns false if the directory structure could
    *  not be obtained or downloading of one file failed.
    */
   static bool download (const std::string &url, const std::string &target, double timeout = 60.0, tl::InputHttpStreamCallback *callback = 0);
diff --git a/src/tl/unit_tests/tlFileUtilsTests.cc b/src/tl/unit_tests/tlFileUtilsTests.cc
index f328b28b17..1397268bd4 100644
--- a/src/tl/unit_tests/tlFileUtilsTests.cc
+++ b/src/tl/unit_tests/tlFileUtilsTests.cc
@@ -285,6 +285,58 @@ TEST (3_NOQT)
   }
 }
 
+TEST (4_mv_dir)
+{
+  std::string tmp_dir = tl::absolute_file_path (tmp_file ());
+  std::string adir = tl::combine_path (tmp_dir, "a");
+
+  std::string b1dir = tl::combine_path (adir, "b1");
+  tl::mkpath (b1dir);
+  EXPECT_EQ (tl::file_exists (b1dir), true);
+
+  std::string b2dir = tl::combine_path (adir, "b2");
+  tl::mkpath (b2dir);
+  EXPECT_EQ (tl::file_exists (b1dir), true);
+
+  {
+    tl::OutputStream os (tl::absolute_file_path (tl::combine_path (b2dir, "x")));
+    os << "hello, world!\n";
+  }
+
+  {
+    tl::OutputStream os (tl::absolute_file_path (tl::combine_path (b2dir, "y")));
+    os << "hello, world II!\n";
+  }
+
+  std::string acopydir = tl::combine_path (tmp_dir, "acopy");
+  tl::rm_dir_recursive (acopydir);
+  tl::mkpath (acopydir);
+
+  tl::mv_dir_recursive (adir, acopydir);
+
+  EXPECT_EQ (tl::file_exists (acopydir), true);
+  EXPECT_EQ (tl::file_exists (adir), false);
+
+  std::string b1copydir = tl::combine_path (acopydir, "b1");
+  EXPECT_EQ (tl::file_exists (b1copydir), true);
+  std::string b2copydir = tl::combine_path (acopydir, "b2");
+  EXPECT_EQ (tl::file_exists (b2copydir), true);
+
+  {
+    std::string xfile = tl::combine_path (b2copydir, "x");
+    EXPECT_EQ (tl::file_exists (xfile), true);
+    tl::InputStream is (xfile);
+    EXPECT_EQ (is.read_all (), "hello, world!\n");
+  }
+
+  {
+    std::string yfile = tl::combine_path (b2copydir, "y");
+    EXPECT_EQ (tl::file_exists (yfile), true);
+    tl::InputStream is (yfile);
+    EXPECT_EQ (is.read_all (), "hello, world II!\n");
+  }
+}
+
 //  Secret mode switchers for testing
 namespace tl
 {
@@ -797,6 +849,13 @@ TEST (18)
     tl::InputStream is (zfile);
     EXPECT_EQ (is.read_all (), "hello, world!\n");
   }
+
+  //  rename directory
+  tl::rename_file (tl::combine_path (tp, "dir"), "dirx");
+
+  EXPECT_EQ (tl::file_exists (tl::combine_path (tp, "dir")), false);
+  EXPECT_EQ (tl::file_exists (tl::combine_path (tp, "dirx")), true);
+  EXPECT_EQ (tl::is_dir (tl::combine_path (tp, "dirx")), true);
 }
 
 //  get_home_path
@@ -816,3 +875,87 @@ TEST (20)
   EXPECT_EQ (tl::absolute_file_path ("~"), tl::get_home_path ());
   EXPECT_EQ (tl::absolute_file_path (tl::combine_path ("~", "test")), tl::combine_path (tl::get_home_path (), "test"));
 }
+
+//  tmpfile
+TEST (21)
+{
+  std::string p = tl::tmpfile ("tl_tests");
+  EXPECT_EQ (tl::file_exists (p), true);
+
+  std::ofstream os (p);
+  os << "A test";
+  os.close ();
+
+  {
+    tl::InputStream is (p);
+    EXPECT_EQ (is.read_all (), "A test");
+  }
+
+  EXPECT_EQ (tl::rm_file (p), true);
+  EXPECT_EQ (tl::file_exists (p), false);
+}
+
+//  TemporaryFile
+TEST (22)
+{
+  std::string p;
+
+  {
+    tl::TemporaryFile tf ("tl_tests");
+    p = tf.path ();
+    EXPECT_EQ (tl::file_exists (tf.path ()), true);
+
+    std::ofstream os (tf.path ());
+    os << "A test";
+    os.close ();
+
+    tl::InputStream is (tf.path ());
+    EXPECT_EQ (is.read_all (), "A test");
+  }
+
+  EXPECT_EQ (tl::file_exists (p), false);
+}
+
+//  tmpdir
+TEST (23)
+{
+  std::string p = tl::tmpdir ("tl_tests");
+  EXPECT_EQ (tl::file_exists (p), true);
+  EXPECT_EQ (tl::is_dir (p), true);
+
+  std::ofstream os (tl::combine_path (p, "test"));
+  os << "A test";
+  os.close ();
+
+  {
+    tl::InputStream is (tl::combine_path (p, "test"));
+    EXPECT_EQ (is.read_all (), "A test");
+  }
+
+  EXPECT_EQ (tl::rm_dir_recursive (p), true);
+  EXPECT_EQ (tl::file_exists (p), false);
+}
+
+//  TemporaryDirectory object
+TEST (24)
+{
+  std::string p;
+
+  {
+    tl::TemporaryDirectory tmpdir ("tl_tests");
+    p = tmpdir.path ();
+
+    EXPECT_EQ (tl::file_exists (p), true);
+    EXPECT_EQ (tl::is_dir (p), true);
+
+    std::ofstream os (tl::combine_path (p, "test"));
+    os << "A test";
+    os.close ();
+
+    tl::InputStream is (tl::combine_path (p, "test"));
+    EXPECT_EQ (is.read_all (), "A test");
+  }
+
+  EXPECT_EQ (tl::file_exists (p), false);
+}
+
diff --git a/src/tl/unit_tests/tlGitTests.cc b/src/tl/unit_tests/tlGitTests.cc
new file mode 100644
index 0000000000..df51035b3f
--- /dev/null
+++ b/src/tl/unit_tests/tlGitTests.cc
@@ -0,0 +1,218 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2023 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#if defined(HAVE_GIT2)
+
+#include "tlGit.h"
+#include "tlUnitTest.h"
+#include "tlFileUtils.h"
+
+static std::string test_url ("https://github.com/klayout/klayout_git_test.git");
+static std::string test_url_invalid ("https://github.com/klayout/doesnotexist.git");
+
+TEST(1_plain)
+{
+  std::string path = tl::TestBase::tmp_file ("repo");
+  tl::GitObject repo (path);
+  repo.read (test_url, std::string (), std::string (), std::string ());
+
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, "LICENSE")), true);
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, ".gitignore")), true);
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, ".git")), false);
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, "src/grain.xml")), true);
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, "src/macros/xsection.lym")), true);
+}
+
+TEST(2_subdir)
+{
+  std::string path = tl::TestBase::tmp_file ("repo");
+  tl::GitObject repo (path);
+  repo.read (test_url, std::string (), std::string ("src"), std::string ());
+
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, "LICENSE")), false);
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, ".gitignore")), false);
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, ".git")), false);
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, "grain.xml")), true);
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, "macros/xsection.lym")), true);
+}
+
+TEST(3_subdir_as_filter)
+{
+  std::string path = tl::TestBase::tmp_file ("repo");
+  tl::GitObject repo (path);
+  repo.read (test_url, std::string ("src/**"), std::string (), std::string ());
+
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, "LICENSE")), false);
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, ".gitignore")), false);
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, ".git")), false);
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, "src/grain.xml")), true);
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, "src/macros/xsection.lym")), true);
+}
+
+TEST(4_single_file)
+{
+  std::string path = tl::TestBase::tmp_file ("repo");
+  tl::GitObject repo (path);
+  repo.read (test_url, std::string ("LICENSE"), std::string (), std::string ());
+
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, "LICENSE")), true);
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, ".gitignore")), false);
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, ".git")), false);
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, "src")), false);
+}
+
+TEST(5_single_file_from_subdir)
+{
+  std::string path = tl::TestBase::tmp_file ("repo");
+  tl::GitObject repo (path);
+  repo.read (test_url, std::string ("grain.xml"), std::string ("src"), std::string ());
+
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, ".git")), false);
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, "grain.xml")), true);
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, "macros")), false);
+
+  tl::InputStream file (tl::combine_path (path, "grain.xml"));
+  tl::TextInputStream grain (file);
+  bool found = false;
+  while (! grain.at_end () && ! found) {
+    std::string line = grain.get_line ();
+    if (line.find ("<version>1.7</version>") != std::string::npos) {
+      found = true;
+    }
+  }
+  EXPECT_EQ (found, true);
+}
+
+TEST(6_branch)
+{
+  std::string path = tl::TestBase::tmp_file ("repo");
+  tl::GitObject repo (path);
+  repo.read (test_url, std::string ("grain.xml"), std::string ("src"), std::string ("wip"));
+
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, ".git")), false);
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, "grain.xml")), true);
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, "macros")), false);
+
+  tl::InputStream file (tl::combine_path (path, "grain.xml"));
+  tl::TextInputStream grain (file);
+  bool found = false;
+  while (! grain.at_end () && ! found) {
+    std::string line = grain.get_line ();
+    if (line.find ("<version>1.4</version>") != std::string::npos) {
+      found = true;
+    }
+  }
+  EXPECT_EQ (found, true);
+}
+
+TEST(7_tag)
+{
+  std::string path = tl::TestBase::tmp_file ("repo");
+  tl::GitObject repo (path);
+  repo.read (test_url, std::string ("grain.xml"), std::string ("src"), std::string ("1.2"));
+
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, ".git")), false);
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, "grain.xml")), true);
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, "macros")), false);
+
+  tl::InputStream file (tl::combine_path (path, "grain.xml"));
+  tl::TextInputStream grain (file);
+  bool found = false;
+  while (! grain.at_end () && ! found) {
+    std::string line = grain.get_line ();
+    if (line.find ("<version>1.2</version>") != std::string::npos) {
+      found = true;
+    }
+  }
+  EXPECT_EQ (found, true);
+}
+
+TEST(8_refspec)
+{
+  std::string path = tl::TestBase::tmp_file ("repo");
+  tl::GitObject repo (path);
+  repo.read (test_url, std::string ("grain.xml"), std::string ("src"), std::string ("refs/tags/1.5"));
+
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, ".git")), false);
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, "grain.xml")), true);
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, "macros")), false);
+
+  tl::InputStream file (tl::combine_path (path, "grain.xml"));
+  tl::TextInputStream grain (file);
+  bool found = false;
+  while (! grain.at_end () && ! found) {
+    std::string line = grain.get_line ();
+    if (line.find ("<version>1.5</version>") != std::string::npos) {
+      found = true;
+    }
+  }
+  EXPECT_EQ (found, true);
+}
+
+TEST(9_HEAD)
+{
+  std::string path = tl::TestBase::tmp_file ("repo");
+  tl::GitObject repo (path);
+  repo.read (test_url, std::string ("grain.xml"), std::string ("src"), std::string ("HEAD"));
+
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, ".git")), false);
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, "grain.xml")), true);
+  EXPECT_EQ (tl::file_exists (tl::combine_path (path, "macros")), false);
+
+  tl::InputStream file (tl::combine_path (path, "grain.xml"));
+  tl::TextInputStream grain (file);
+  bool found = false;
+  while (! grain.at_end () && ! found) {
+    std::string line = grain.get_line ();
+    if (line.find ("<version>1.7</version>") != std::string::npos) {
+      found = true;
+    }
+  }
+  EXPECT_EQ (found, true);
+}
+
+TEST(10_invalid_branch)
+{
+  std::string path = tl::TestBase::tmp_file ("repo");
+  tl::GitObject repo (path);
+  try {
+    repo.read (test_url, std::string (), std::string (), std::string ("brxxx"));
+    EXPECT_EQ (true, false);
+  } catch (tl::Exception &ex) {
+    EXPECT_EQ (ex.msg (), "Git checkout - Unable to resolve reference name: brxxx");
+  }
+}
+
+TEST(11_invalid_url)
+{
+  std::string path = tl::TestBase::tmp_file ("repo");
+  tl::GitObject repo (path);
+  try {
+    repo.read (test_url_invalid, std::string (), std::string (), std::string ("brxxx"));
+    EXPECT_EQ (true, false);
+  } catch (tl::Exception &ex) {
+    EXPECT_EQ (ex.msg (), "Error cloning Git repo: anonymous access is supported only, but server requests credentials");
+  }
+}
+
+#endif
+
diff --git a/src/tl/unit_tests/unit_tests.pro b/src/tl/unit_tests/unit_tests.pro
index c648dcb1b6..2e0bab9099 100644
--- a/src/tl/unit_tests/unit_tests.pro
+++ b/src/tl/unit_tests/unit_tests.pro
@@ -20,6 +20,7 @@ SOURCES = \
   tlExpressionTests.cc \
   tlFileSystemWatcherTests.cc \
   tlFileUtilsTests.cc \
+  tlGitTests.cc \
   tlHttpStreamTests.cc \
   tlIncludeTests.cc \
   tlInt128SupportTests.cc \
diff --git a/src/unit_tests/unit_test_main.cc b/src/unit_tests/unit_test_main.cc
index 75c8f78097..2837663bdb 100644
--- a/src/unit_tests/unit_test_main.cc
+++ b/src/unit_tests/unit_test_main.cc
@@ -433,6 +433,8 @@ run_tests (const std::vector<tl::TestBase *> &selected_tests, bool editable, boo
 static int
 main_cont (int &argc, char **argv)
 {
+  ut::TestConsole console (stdout);
+
   std::unique_ptr<rba::RubyInterpreter> ruby_interpreter;
   std::unique_ptr<pya::PythonInterpreter> python_interpreter;
 
@@ -452,8 +454,6 @@ main_cont (int &argc, char **argv)
 
   int result = 0;
 
-  ut::TestConsole console (stdout);
-
   try {
 
     pya::PythonInterpreter::initialize ();