diff --git a/.pylintrc b/.pylintrc
new file mode 100644
--- /dev/null
+++ b/.pylintrc
@@ -0,0 +1,7 @@
+# add root folder to Pylint PYTHONPATH, so builders can be checked with zorg.*
+# packages
+[MASTER]
+init-hook='import sys; sys.path.append(".")'
+
+[FORMAT]
+max-line-length=120
diff --git a/zorg/buildbot/builders/ClangBuilder.py b/zorg/buildbot/builders/ClangBuilder.py
--- a/zorg/buildbot/builders/ClangBuilder.py
+++ b/zorg/buildbot/builders/ClangBuilder.py
@@ -4,6 +4,7 @@
 from buildbot.process.properties import WithProperties, Property
 from buildbot.steps.shell import ShellCommand, SetProperty
 from buildbot.steps.shell import WarningCountingShellCommand
+from buildbot.steps.worker import RemoveDirectory
 
 import zorg.buildbot.builders.Util as builders_util
 
@@ -309,15 +310,17 @@
 
 
     ############# CLEANING
-    f.addStep(ShellCommand(name='clean stage 1',
-                           command=['rm','-rf',stage1_build],
-                           warnOnFailure=True,
-                           haltOnFailure=False,
-                           flunkOnFailure=False,
-                           description='cleaning stage 1',
-                           descriptionDone='clean',
-                           workdir='.',
-                           doStepIf=clean_build_requested))
+    # Use the buildbot build-in step "RemoveDirectory".
+    # http://docs.buildbot.net/current/manual/configuration/buildsteps.html#removedirectory
+    f.addStep(RemoveDirectory(name='clean stage 1',
+                              dir=stage1_build,
+                              warnOnFailure=True,
+                              haltOnFailure=False,
+                              flunkOnFailure=False,
+                              description='cleaning stage 1',
+                              descriptionDone='clean',
+                              workdir='.',
+                              doStepIf=clean_build_requested))
 
 
     ############# STAGE 1
@@ -357,14 +360,14 @@
                                  env=env))
 
     if useTwoStage or runTestSuite or stage1_upload_directory:
-        f.addStep(ShellCommand(name='clean stage 1 install',
-                               command=['rm','-rf',stage1_install],
-                               warnOnFailure=True,
-                               haltOnFailure=False,
-                               flunkOnFailure=False,
-                               description='cleaning stage 1 install',
-                               descriptionDone='clean',
-                               workdir='.'))
+        f.addStep(RemoveDirectory(name='clean stage 1 install',
+                            dir=stage1_install,
+                            warnOnFailure=True,
+                            haltOnFailure=False,
+                            flunkOnFailure=False,
+                            description='cleaning stage 1 install',
+                            descriptionDone='clean',
+                            workdir='.'))
         f.addStep(ShellCommand(name='install stage 1',
                                command=ninja_install_cmd,
                                description='ninja install',
@@ -393,12 +396,13 @@
         # changed on the stage 1, we cannot trust any of the intermediate file
         # from the old compiler. And if the stage 1 compiler is the same, we
         # should not build in the first place.
-        f.addStep(ShellCommand(name='clean stage 2',
-                               command=['rm','-rf',stage2_build],
-                               warnOnFailure=True,
-                               description='cleaning stage 2',
-                               descriptionDone='clean',
-                               workdir='.'))
+        f.addStep(RemoveDirectory(name='clean stage 2',
+                                  dir=stage2_build,
+                                  warnOnFailure=True,
+                                  description='cleaning stage 2',
+                                  descriptionDone='clean',
+                                  workdir='.'))
+
 
         # Absolute paths to just built compilers.
         # Note: Backslash path separators do not work well with cmake and ninja.
@@ -450,12 +454,13 @@
         compiler_path = stage1_install
         if useTwoStage:
             compiler_path=stage2_install
-            f.addStep(ShellCommand(name='clean stage 2 install',
-                                   command=['rm','-rf',stage2_install],
-                                   warnOnFailure=True,
-                                   description='cleaning stage 2 install',
-                                   descriptionDone='clean',
-                                   workdir='.'))
+            f.addStep(RemoveDirectory(name='clean stage 2 install',
+                                      dir=stage2_install,
+                                      warnOnFailure=True,
+                                      description='cleaning stage 2 install',
+                                      descriptionDone='clean',
+                                      workdir='.'))
+
             f.addStep(ShellCommand(name='install stage 2',
                                    command=ninja_install_cmd,
                                    description='ninja install 2',
@@ -514,12 +519,13 @@
         test_suite_env['CXX'] = cxx
 
         # Steps to prepare, build and run LNT
-        f.addStep(ShellCommand(name='clean sandbox',
-                               command=['rm', '-rf', 'sandbox'],
-                               haltOnFailure=True,
-                               description='removing sandbox directory',
-                               workdir='test',
-                               env=env))
+        f.addStep(RemoveDirectory(name='clean sandbox',
+                                  dir='sandbox',
+                                  haltOnFailure=True,
+                                  description='removing sandbox directory',
+                                  workdir='test',
+                                  env=env))
+
         f.addStep(ShellCommand(name='recreate sandbox',
                                command=['virtualenv', 'sandbox'],
                                haltOnFailure=True,