diff --git a/requirements-dev.txt b/requirements-dev.txt
index cd3f5bb..0151049 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -1,5 +1,34 @@
+bitarray==1.8.1
+    # via
+    #   -r https://osm.etsi.org/gitweb/?p=osm/IM.git;a=blob_plain;f=requirements.txt;hb=master
+    #   pyangbind
+enum34==1.1.10
+    # via
+    #   -r https://osm.etsi.org/gitweb/?p=osm/IM.git;a=blob_plain;f=requirements.txt;hb=master
+    #   pyangbind
+lxml==4.6.3
+    # via
+    #   -r https://osm.etsi.org/gitweb/?p=osm/IM.git;a=blob_plain;f=requirements.txt;hb=master
+    #   pyang
+    #   pyangbind
 git+https://osm.etsi.org/gerrit/osm/IM.git@master#egg=osm-im
     # via -r requirements-dev.in
+pyang==2.4.0
+    # via
+    #   -r https://osm.etsi.org/gitweb/?p=osm/IM.git;a=blob_plain;f=requirements.txt;hb=master
+    #   pyangbind
+pyangbind==0.8.1
+    # via -r https://osm.etsi.org/gitweb/?p=osm/IM.git;a=blob_plain;f=requirements.txt;hb=master
+pyyaml==5.4.1
+    # via -r https://osm.etsi.org/gitweb/?p=osm/IM.git;a=blob_plain;f=requirements.txt;hb=master
+regex==2021.3.17
+    # via
+    #   -r https://osm.etsi.org/gitweb/?p=osm/IM.git;a=blob_plain;f=requirements.txt;hb=master
+    #   pyangbind
+six==1.15.0
+    # via
+    #   -r https://osm.etsi.org/gitweb/?p=osm/IM.git;a=blob_plain;f=requirements.txt;hb=master
+    #   pyangbind
 #######################################################################################
 # Copyright ETSI Contributors and Others.
 #