diff --git a/libraries/entropy/spm/plugins/interfaces/portage_plugin/__init__.py b/libraries/entropy/spm/plugins/interfaces/portage_plugin/__init__.py
index d3239dc37..2da46e11a 100644
--- a/libraries/entropy/spm/plugins/interfaces/portage_plugin/__init__.py
+++ b/libraries/entropy/spm/plugins/interfaces/portage_plugin/__init__.py
@@ -28,8 +28,8 @@ from entropy.const import etpConst, etpUi, const_get_stringtype, \
     const_setup_file
 from entropy.exceptions import FileNotFound, SPMError, InvalidDependString, \
     InvalidAtom, EntropyException
-from entropy.output import darkred, darkgreen, brown, darkblue, purple, red, \
-    bold, blue, getcolor, decolorize
+from entropy.output import darkred, darkgreen, brown, darkblue, teal, purple, \
+    red, bold, blue, getcolor, decolorize
 from entropy.i18n import _
 from entropy.core.settings.base import SystemSettings
 from entropy.misc import LogFile
@@ -351,7 +351,7 @@ class PortagePlugin(SpmPlugin):
         'global_make_profile': "/etc/make.profile",
     }
 
-    PLUGIN_API_VERSION = 7
+    PLUGIN_API_VERSION = 8
 
     SUPPORTED_MATCH_TYPES = [
         "bestmatch-visible", "cp-list", "list-visible", "match-all",
@@ -3158,6 +3158,62 @@ class PortagePlugin(SpmPlugin):
 
         return 0
 
+    @staticmethod
+    def _qa_check_preserved_libraries(entropy_output, portage):
+        """
+        Ask portage whether there are preserved libraries on the system.
+        This usually indicates that Entropy packages should not be really
+        pushed.
+        """
+        root = etpConst['systemroot'] + os.path.sep
+        mytree = portage.vartree(root=root)
+        vardb = mytree.dbapi
+        vardb._plib_registry.load()
+        if vardb._plib_registry.hasEntries():
+            # just warn for now
+            entropy_output.output("", importance = 0, level = "warning")
+            txt = "%s: %s:" % (
+                teal(_("Attention")),
+                purple(_("preserved libraries have been found on system")),
+            )
+            entropy_output.output(txt,
+                importance = 1,
+                level = "warning",
+                header = brown(_(" !!! ")),
+            )
+            preserved_libs = vardb._plib_registry.getPreservedLibs()
+            for cpv, path_list in preserved_libs.items():
+                if path_list:
+                    entropy_output.output(
+                        darkblue(cpv),
+                        importance = 0,
+                        level = "warning",
+                        header = teal(_(" @@ ")),
+                    )
+                for path in path_list:
+                    entropy_output.output(
+                        path,
+                        importance = 0,
+                        level = "warning",
+                        header = purple(_("    # ")),
+                    )
+            entropy_output.output("", importance = 0, level = "warning")
+        return 0, None
+
+    @staticmethod
+    def execute_system_qa_tests(entropy_output):
+        """
+        Reimplemented from SpmPlugin class.
+        """
+        import portage
+        methods = (PortagePlugin._qa_check_preserved_libraries,)
+        for method in methods:
+            exit_st, msg = method(entropy_output, portage)
+            if exit_st != 0:
+                return exit_st, msg
+
+        return 0, ""
+
     @staticmethod
     def execute_qa_tests(package_path):
         """
diff --git a/libraries/entropy/spm/plugins/skel.py b/libraries/entropy/spm/plugins/skel.py
index f9e395ec1..f5f51dd1f 100644
--- a/libraries/entropy/spm/plugins/skel.py
+++ b/libraries/entropy/spm/plugins/skel.py
@@ -22,7 +22,7 @@ import entropy.tools
 class SpmPlugin(Singleton):
     """Base class for Source Package Manager plugins"""
 
-    BASE_PLUGIN_API_VERSION = 7
+    BASE_PLUGIN_API_VERSION = 8
 
     # this must be reimplemented by subclasses and value
     # must match BASE_PLUGIN_API_VERSION
@@ -700,6 +700,24 @@ class SpmPlugin(Singleton):
         """
         raise NotImplementedError()
 
+    @staticmethod
+    def execute_system_qa_tests(entropy_output):
+        """
+        Execute Source Package Manager based QA tests on the whole system.
+        This method can be used to make sure that at the time of pushing
+        a new Entropy repository, the system is in consistent state.
+        It is called by Entropy Server, during pre-repository upload QA
+        checks. This method must return a tuple composed by exit status and
+        error message. Error message is considered only if exit status != 0.
+
+        @param entropy_output: a valid text output interface
+        @type entropy_output: TextInterface object
+        @return: tuple composed by error status and error message (if any).
+            Error status is an int with != 0 values if error occured.
+        @rtype: tuple
+        """
+        raise NotImplementedError()
+
     def append_metadata_to_package(self, entropy_package_name, package_path):
         """
         Append Source Package Manager metadata bits to an Entropy package,