diff --git a/requirements-dev.in b/requirements-dev.in
index dc09a5e..ae6bd6a 100644
--- a/requirements-dev.in
+++ b/requirements-dev.in
@@ -14,7 +14,7 @@
 # limitations under the License.
 
 git+https://osm.etsi.org/gerrit/osm/IM.git@master#egg=osm-im
--r https://osm.etsi.org/gitweb/?p=osm/IM.git;a=blob_plain;f=requirements.txt;hb=master
+-r https://osm.etsi.org/gitweb/?p=osm/IM.git;a=blob_plain;f=requirements.txt;hb=v13.0
 
 git+https://osm.etsi.org/gerrit/osm/osmclient.git@master#egg=osm-osmclient
--r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=master
+-r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=v13.0
diff --git a/requirements-dev.txt b/requirements-dev.txt
index 9cdc309..2396ab6 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -16,80 +16,80 @@
 #######################################################################################
 bitarray==2.5.1
     # via
-    #   -r https://osm.etsi.org/gitweb/?p=osm/IM.git;a=blob_plain;f=requirements.txt;hb=master
+    #   -r https://osm.etsi.org/gitweb/?p=osm/IM.git;a=blob_plain;f=requirements.txt;hb=v13.0
     #   pyangbind
 certifi==2022.6.15
     # via
-    #   -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=master
+    #   -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=v13.0
     #   requests
 charset-normalizer==2.0.12
     # via
-    #   -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=master
+    #   -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=v13.0
     #   requests
 click==8.1.3
-    # via -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=master
+    # via -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=v13.0
 enum34==1.1.10
     # via
-    #   -r https://osm.etsi.org/gitweb/?p=osm/IM.git;a=blob_plain;f=requirements.txt;hb=master
+    #   -r https://osm.etsi.org/gitweb/?p=osm/IM.git;a=blob_plain;f=requirements.txt;hb=v13.0
     #   pyangbind
 idna==3.3
     # via
-    #   -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=master
+    #   -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=v13.0
     #   requests
 jinja2==3.1.2
-    # via -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=master
+    # via -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=v13.0
 lxml==4.9.0
     # via
-    #   -r https://osm.etsi.org/gitweb/?p=osm/IM.git;a=blob_plain;f=requirements.txt;hb=master
+    #   -r https://osm.etsi.org/gitweb/?p=osm/IM.git;a=blob_plain;f=requirements.txt;hb=v13.0
     #   pyang
     #   pyangbind
 markupsafe==2.1.1
     # via
-    #   -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=master
+    #   -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=v13.0
     #   jinja2
 osm-im @ git+https://osm.etsi.org/gerrit/osm/IM.git@master
     # via -r requirements-dev.in
 osmclient @ git+https://osm.etsi.org/gerrit/osm/osmclient.git@master
     # via -r requirements-dev.in
 packaging==21.3
-    # via -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=master
+    # via -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=v13.0
 prettytable==3.3.0
-    # via -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=master
+    # via -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=v13.0
 pyang==2.5.3
     # via
-    #   -r https://osm.etsi.org/gitweb/?p=osm/IM.git;a=blob_plain;f=requirements.txt;hb=master
+    #   -r https://osm.etsi.org/gitweb/?p=osm/IM.git;a=blob_plain;f=requirements.txt;hb=v13.0
     #   pyangbind
 pyangbind==0.8.1
-    # via -r https://osm.etsi.org/gitweb/?p=osm/IM.git;a=blob_plain;f=requirements.txt;hb=master
+    # via -r https://osm.etsi.org/gitweb/?p=osm/IM.git;a=blob_plain;f=requirements.txt;hb=v13.0
 pycurl==7.45.1
-    # via -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=master
+    # via -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=v13.0
 pyparsing==3.0.9
     # via
-    #   -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=master
+    #   -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=v13.0
     #   packaging
 python-magic==0.4.27
-    # via -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=master
+    # via -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=v13.0
 pyyaml==5.4.1
     # via
-    #   -r https://osm.etsi.org/gitweb/?p=osm/IM.git;a=blob_plain;f=requirements.txt;hb=master
-    #   -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=master
+    #   -r https://osm.etsi.org/gitweb/?p=osm/IM.git;a=blob_plain;f=requirements.txt;hb=v13.0
+    #   -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=v13.0
 regex==2022.6.2
     # via
-    #   -r https://osm.etsi.org/gitweb/?p=osm/IM.git;a=blob_plain;f=requirements.txt;hb=master
+    #   -r https://osm.etsi.org/gitweb/?p=osm/IM.git;a=blob_plain;f=requirements.txt;hb=v13.0
     #   pyangbind
 requests==2.28.0
-    # via -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=master
+    # via -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=v13.0
 six==1.16.0
     # via
-    #   -r https://osm.etsi.org/gitweb/?p=osm/IM.git;a=blob_plain;f=requirements.txt;hb=master
+    #   -r https://osm.etsi.org/gitweb/?p=osm/IM.git;a=blob_plain;f=requirements.txt;hb=v13.0
     #   pyangbind
 urllib3==1.26.9
     # via
-    #   -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=master
+    #   -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=v13.0
     #   requests
 verboselogs==1.7
-    # via -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=master
+    # via -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=v13.0
 wcwidth==0.2.5
     # via
-    #   -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=master
+    #   -r https://osm.etsi.org/gitweb/?p=osm/osmclient.git;a=blob_plain;f=requirements.txt;hb=v13.0
     #   prettytable
diff --git a/tox.ini b/tox.ini
index 81860e5..2898650 100644
--- a/tox.ini
+++ b/tox.ini
@@ -45,7 +45,7 @@
 
 #######################################################################################
 [testenv:flake8]
-deps = flake8
+deps = flake8==5.0.4
 commands =
         flake8 robot-systest