diff --git a/rules/klayout/macros/gf180mcu_drc.lydrc b/rules/klayout/macros/gf180mcu_drc.lydrc
index cd1e0740..11bfa2c7 100644
--- a/rules/klayout/macros/gf180mcu_drc.lydrc
+++ b/rules/klayout/macros/gf180mcu_drc.lydrc
@@ -78,13 +78,9 @@ elsif options["variant"] == "C"
   $metal_level = "5LM"
   $mim_option = "B"
 elsif options["variant"] == "D"
-  $metal_top = "9K"
-  $metal_level = "6LM"
+  $metal_top = "11K"
+  $metal_level = "5LM"
   $mim_option = "B"
-elsif options["variant"] == "E"
-  $metal_top = "9K"
-  $metal_level = "6LM"
-  $mim_option = "A"
 end
 
 $topcell = options["top_cell_name"]
diff --git a/rules/klayout/macros/gf180mcu_options.lym b/rules/klayout/macros/gf180mcu_options.lym
index 7c519b68..699e5448 100644
--- a/rules/klayout/macros/gf180mcu_options.lym
+++ b/rules/klayout/macros/gf180mcu_options.lym
@@ -59,7 +59,7 @@ require 'yaml'
   variant_drc_action.title = "Variant options"
   variant_drc_action.on_triggered do
     
-    variant_select = RBA::InputDialog::ask_item("Variant options", "Select variant option:", [ "A", "B", "C" , "D", "E"], 2)
+    variant_select = RBA::InputDialog::ask_item("Variant options", "Select variant option:", [ "A", "B", "C" , "D"], 2)
       options = YAML.load(File.read(__dir__ + "/drc_options.yml"))
       if variant_select
         options["variant"] = variant_select
diff --git a/rules/klayout/macros/run_drc_main/layers_def.drc b/rules/klayout/macros/run_drc_main/layers_def.drc
new file mode 100644
index 00000000..78519d01
--- /dev/null
+++ b/rules/klayout/macros/run_drc_main/layers_def.drc
@@ -0,0 +1,636 @@
+# frozen_string_literal: true
+
+################################################################################################
+# Copyright 2023 GlobalFoundries PDK Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+################################################################################################
+
+#================================================
+#------------- LAYERS DEFINITIONS ---------------
+#================================================
+
+polygons_count = 0
+logger.info('Read in polygons from layers.')
+
+def get_polygons(layer, data_type)
+  ps = polygons(layer, data_type)
+  $run_mode == 'deep' ? ps : ps.merged
+end
+
+comp = get_polygons(22, 0)
+count = comp.count
+logger.info("comp has #{count} polygons")
+polygons_count += count
+
+dnwell = get_polygons(12, 0)
+count = dnwell.count
+logger.info("dnwell has #{count} polygons")
+polygons_count += count
+
+nwell = get_polygons(21, 0)
+count = nwell.count
+logger.info("nwell has #{count} polygons")
+polygons_count += count
+
+lvpwell = get_polygons(204, 0)
+count = lvpwell.count
+logger.info("lvpwell has #{count} polygons")
+polygons_count += count
+
+dualgate = get_polygons(55, 0)
+count = dualgate.count
+logger.info("dualgate has #{count} polygons")
+polygons_count += count
+
+poly2 = get_polygons(30, 0)
+count = poly2.count
+logger.info("poly2 has #{count} polygons")
+polygons_count += count
+
+nplus = get_polygons(32, 0)
+count = nplus.count
+logger.info("nplus has #{count} polygons")
+polygons_count += count
+
+pplus = get_polygons(31, 0)
+count = pplus.count
+logger.info("pplus has #{count} polygons")
+polygons_count += count
+
+sab = get_polygons(49, 0)
+count = sab.count
+logger.info("sab has #{count} polygons")
+polygons_count += count
+
+esd = get_polygons(24, 0)
+count = esd.count
+logger.info("esd has #{count} polygons")
+polygons_count += count
+
+resistor = get_polygons(62, 0)
+count = resistor.count
+logger.info("resistor has #{count} polygons")
+polygons_count += count
+
+fhres = get_polygons(227, 0)
+count = fhres.count
+logger.info("fhres has #{count} polygons")
+polygons_count += count
+
+fusetop = get_polygons(75, 0)
+count = fusetop.count
+logger.info("fusetop has #{count} polygons")
+polygons_count += count
+
+fusewindow_d = get_polygons(96, 1)
+count = fusewindow_d.count
+logger.info("fusewindow_d has #{count} polygons")
+polygons_count += count
+
+polyfuse = get_polygons(220, 0)
+count = polyfuse.count
+logger.info("polyfuse has #{count} polygons")
+polygons_count += count
+
+mvsd = get_polygons(210, 0)
+count = mvsd.count
+logger.info("mvsd has #{count} polygons")
+polygons_count += count
+
+mvpsd = get_polygons(11, 39)
+count = mvpsd.count
+logger.info("mvpsd has #{count} polygons")
+polygons_count += count
+
+nat = get_polygons(5, 0)
+count = nat.count
+logger.info("nat has #{count} polygons")
+polygons_count += count
+
+comp_dummy = get_polygons(22, 4)
+count = comp_dummy.count
+logger.info("comp_dummy has #{count} polygons")
+polygons_count += count
+
+poly2_dummy = get_polygons(30, 4)
+count = poly2_dummy.count
+logger.info("poly2_dummy has #{count} polygons")
+polygons_count += count
+
+schottky_diode = get_polygons(241, 0)
+count = schottky_diode.count
+logger.info("schottky_diode has #{count} polygons")
+polygons_count += count
+
+zener = get_polygons(178, 0)
+count = zener.count
+logger.info("zener has #{count} polygons")
+polygons_count += count
+
+res_mk = get_polygons(110, 5)
+count = res_mk.count
+logger.info("res_mk has #{count} polygons")
+polygons_count += count
+
+opc_drc = get_polygons(124, 5)
+count = opc_drc.count
+logger.info("opc_drc has #{count} polygons")
+polygons_count += count
+
+v5_xtor = get_polygons(112, 1)
+count = v5_xtor.count
+logger.info("v5_xtor has #{count} polygons")
+polygons_count += count
+
+cap_mk = get_polygons(117, 5)
+count = cap_mk.count
+logger.info("cap_mk has #{count} polygons")
+polygons_count += count
+
+mos_cap_mk = get_polygons(166, 5)
+count = mos_cap_mk.count
+logger.info("mos_cap_mk has #{count} polygons")
+polygons_count += count
+
+ind_mk = get_polygons(151, 5)
+count = ind_mk.count
+logger.info("ind_mk has #{count} polygons")
+polygons_count += count
+
+diode_mk = get_polygons(115, 5)
+count = diode_mk.count
+logger.info("diode_mk has #{count} polygons")
+polygons_count += count
+
+drc_bjt = get_polygons(127, 5)
+count = drc_bjt.count
+logger.info("drc_bjt has #{count} polygons")
+polygons_count += count
+
+lvs_bjt = get_polygons(118, 5)
+count = lvs_bjt.count
+logger.info("lvs_bjt has #{count} polygons")
+polygons_count += count
+
+mim_l_mk = get_polygons(117, 10)
+count = mim_l_mk.count
+logger.info("mim_l_mk has #{count} polygons")
+polygons_count += count
+
+latchup_mk = get_polygons(137, 5)
+count = latchup_mk.count
+logger.info("latchup_mk has #{count} polygons")
+polygons_count += count
+
+guard_ring_mk = get_polygons(167, 5)
+count = guard_ring_mk.count
+logger.info("guard_ring_mk has #{count} polygons")
+polygons_count += count
+
+otp_mk = get_polygons(173, 5)
+count = otp_mk.count
+logger.info("otp_mk has #{count} polygons")
+polygons_count += count
+
+mtpmark = get_polygons(122, 5)
+count = mtpmark.count
+logger.info("mtpmark has #{count} polygons")
+polygons_count += count
+
+neo_ee_mk = get_polygons(88, 17)
+count = neo_ee_mk.count
+logger.info("neo_ee_mk has #{count} polygons")
+polygons_count += count
+
+sramcore = get_polygons(108, 5)
+count = sramcore.count
+logger.info("sramcore has #{count} polygons")
+polygons_count += count
+
+lvs_rf = get_polygons(100, 5)
+count = lvs_rf.count
+logger.info("lvs_rf has #{count} polygons")
+polygons_count += count
+
+lvs_drain = get_polygons(100, 7)
+count = lvs_drain.count
+logger.info("lvs_drain has #{count} polygons")
+polygons_count += count
+
+ind_mk = get_polygons(151, 5)
+count = ind_mk.count
+logger.info("ind_mk has #{count} polygons")
+polygons_count += count
+
+hvpolyrs = get_polygons(123, 5)
+count = hvpolyrs.count
+logger.info("hvpolyrs has #{count} polygons")
+polygons_count += count
+
+lvs_io = get_polygons(119, 5)
+count = lvs_io.count
+logger.info("lvs_io has #{count} polygons")
+polygons_count += count
+
+probe_mk = get_polygons(13, 17)
+count = probe_mk.count
+logger.info("probe_mk has #{count} polygons")
+polygons_count += count
+
+esd_mk = get_polygons(24, 5)
+count = esd_mk.count
+logger.info("esd_mk has #{count} polygons")
+polygons_count += count
+
+lvs_source = get_polygons(100, 8)
+count = lvs_source.count
+logger.info("lvs_source has #{count} polygons")
+polygons_count += count
+
+well_diode_mk = get_polygons(153, 51)
+count = well_diode_mk.count
+logger.info("well_diode_mk has #{count} polygons")
+polygons_count += count
+
+ldmos_xtor = get_polygons(226, 0)
+count = ldmos_xtor.count
+logger.info("ldmos_xtor has #{count} polygons")
+polygons_count += count
+
+plfuse = get_polygons(125, 5)
+count = plfuse.count
+logger.info("plfuse has #{count} polygons")
+polygons_count += count
+
+efuse_mk = get_polygons(80, 5)
+count = efuse_mk.count
+logger.info("efuse_mk has #{count} polygons")
+polygons_count += count
+
+mcell_feol_mk = get_polygons(11, 17)
+count = mcell_feol_mk.count
+logger.info("mcell_feol_mk has #{count} polygons")
+polygons_count += count
+
+ymtp_mk = get_polygons(86, 17)
+count = ymtp_mk.count
+logger.info("ymtp_mk has #{count} polygons")
+polygons_count += count
+
+dev_wf_mk = get_polygons(128, 17)
+count = dev_wf_mk.count
+logger.info("dev_wf_mk has #{count} polygons")
+polygons_count += count
+
+comp_label = get_polygons(22, 10)
+count = comp_label.count
+logger.info("comp_label has #{count} polygons")
+polygons_count += count
+
+poly2_label = get_polygons(30, 10)
+count = poly2_label.count
+logger.info("poly2_label has #{count} polygons")
+polygons_count += count
+
+mdiode = get_polygons(116, 5)
+count = mdiode.count
+logger.info("mdiode has #{count} polygons")
+polygons_count += count
+
+ndmy = get_polygons(111, 5)
+count = ndmy.count
+logger.info("ndmy has #{count} polygons")
+polygons_count += count
+
+pmndmy = get_polygons(152, 5)
+count = pmndmy.count
+logger.info("pmndmy has #{count} polygons")
+polygons_count += count
+
+# == CONTACT LAYER ==
+contact_tables = %w[contact contact_split efuse geom dnwell nwell lvpwell nat
+                    hres ldnmos ldpmos lres otp_mk pres sab sram_3p3 sram_5p0 main]
+
+if contact_tables.include?(TABLE_NAME)
+  contact = get_polygons(33, 0)
+  count = contact.count
+  logger.info("contact has #{count} polygons")
+  polygons_count += count
+end
+
+metal1_drawn = get_polygons(34, 0)
+count = metal1_drawn.count
+logger.info("metal1_drawn has #{count} polygons")
+polygons_count += count
+
+metal1_dummy = get_polygons(34, 4)
+count = metal1_dummy.count
+logger.info("metal1_dummy has #{count} polygons")
+polygons_count += count
+
+metal1         = metal1_drawn + metal1_dummy
+
+metal1_label = get_polygons(34, 10)
+count = metal1_label.count
+logger.info("metal1_label has #{count} polygons")
+polygons_count += count
+
+metal1_slot = get_polygons(34, 3)
+count = metal1_slot.count
+logger.info("metal1_slot has #{count} polygons")
+polygons_count += count
+
+metal1_blk = get_polygons(34, 5)
+count = metal1_blk.count
+logger.info("metal1_blk has #{count} polygons")
+polygons_count += count
+
+# == VIA1 LAYER ==
+via1_tables = %w[geom mim_a mim_b metaltop_30k via1 via1_split
+                 dnwell nwell lvpwell nat main]
+
+if via1_tables.include?(TABLE_NAME)
+  via1 = get_polygons(35, 0)
+  count = via1.count
+  logger.info("via1 has #{count} polygons")
+  polygons_count += count
+end
+
+metal2_drawn = get_polygons(36, 0)
+count = metal2_drawn.count
+logger.info("metal2_drawn has #{count} polygons")
+polygons_count += count
+
+metal2_dummy = get_polygons(36, 4)
+count = metal2_dummy.count
+logger.info("metal2_dummy has #{count} polygons")
+polygons_count += count
+
+metal2 = metal2_drawn + metal2_dummy
+
+metal2_label = get_polygons(36, 10)
+count = metal2_label.count
+logger.info("metal2_label has #{count} polygons")
+polygons_count += count
+
+metal2_slot = get_polygons(36, 3)
+count = metal2_slot.count
+logger.info("metal2_slot has #{count} polygons")
+polygons_count += count
+
+metal2_blk = get_polygons(36, 5)
+count = metal2_blk.count
+logger.info("metal2_blk has #{count} polygons")
+polygons_count += count
+
+# == VIA2 LAYER ==
+via2_tables = %w[geom mim_a mim_b metaltop_30k dnwell
+                 nwell lvpwell nat via2 via2_split main]
+
+case METAL_LEVEL
+when '3LM', '4LM', '5LM', '6LM'
+
+  if via2_tables.include?(TABLE_NAME)
+    via2 = get_polygons(38, 0)
+    count = via2.count
+    logger.info("via2 has #{count} polygons")
+    polygons_count += count
+  end
+
+  metal3_drawn = get_polygons(42, 0)
+  count = metal3_drawn.count
+  logger.info("metal3_drawn has #{count} polygons")
+  polygons_count += count
+
+  metal3_dummy = get_polygons(42, 4)
+  count = metal3_dummy.count
+  logger.info("metal3_dummy has #{count} polygons")
+  polygons_count += count
+
+  metal3 = metal3_drawn + metal3_dummy
+
+  metal3_label = get_polygons(42, 10)
+  count = metal3_label.count
+  logger.info("metal3_label has #{count} polygons")
+  polygons_count += count
+
+  metal3_slot = get_polygons(42, 3)
+  count = metal3_slot.count
+  logger.info("metal3_slot has #{count} polygons")
+  polygons_count += count
+
+  metal3_blk = get_polygons(42, 5)
+  count = metal3_blk.count
+  logger.info("metal3_blk has #{count} polygons")
+  polygons_count += count
+end
+
+case METAL_LEVEL
+when '4LM', '5LM', '6LM'
+  via3 = get_polygons(40, 0)
+  count = via3.count
+  logger.info("via3 has #{count} polygons")
+  polygons_count += count
+
+  metal4_drawn = get_polygons(46, 0)
+  count = metal4_drawn.count
+  logger.info("metal4_drawn has #{count} polygons")
+  polygons_count += count
+
+  metal4_dummy = get_polygons(46, 4)
+  count = metal4_dummy.count
+  logger.info("metal4_dummy has #{count} polygons")
+  polygons_count += count
+
+  metal4 = metal4_drawn + metal4_dummy
+
+  metal4_label = get_polygons(46, 10)
+  count = metal4_label.count
+  logger.info("metal4_label has #{count} polygons")
+  polygons_count += count
+
+  metal4_slot = get_polygons(46, 3)
+  count = metal4_slot.count
+  logger.info("metal4_slot has #{count} polygons")
+  polygons_count += count
+
+  metal4_blk = get_polygons(46, 5)
+  count = metal4_blk.count
+  logger.info("metal4_blk has #{count} polygons")
+  polygons_count += count
+end
+
+case METAL_LEVEL
+when '5LM', '6LM'
+  via4 = get_polygons(41, 0)
+  count = via4.count
+  logger.info("via4 has #{count} polygons")
+  polygons_count += count
+
+  metal5_drawn = get_polygons(81, 0)
+  count = metal5_drawn.count
+  logger.info("metal5_drawn has #{count} polygons")
+  polygons_count += count
+
+  metal5_dummy = get_polygons(81, 4)
+  count = metal5_dummy.count
+  logger.info("metal5_dummy has #{count} polygons")
+  polygons_count += count
+
+  metal5 = metal5_drawn + metal5_dummy
+
+  metal5_label = get_polygons(81, 10)
+  count = metal5_label.count
+  logger.info("metal5_label has #{count} polygons")
+  polygons_count += count
+
+  metal5_slot = get_polygons(81, 3)
+  count = metal5_slot.count
+  logger.info("metal5_slot has #{count} polygons")
+  polygons_count += count
+
+  metal5_blk = get_polygons(81, 5)
+  count = metal5_blk.count
+  logger.info("metal5_blk has #{count} polygons")
+  polygons_count += count
+end
+
+case METAL_LEVEL
+when '6LM'
+  via5 = get_polygons(82, 0)
+  count = via5.count
+  logger.info("via5 has #{count} polygons")
+  polygons_count += count
+
+  metaltop_drawn = get_polygons(53, 0)
+  count = metaltop_drawn.count
+  logger.info("metaltop_drawn has #{count} polygons")
+  polygons_count += count
+
+  metaltop_dummy = get_polygons(53, 4)
+  count = metaltop_dummy.count
+  logger.info("metaltop_dummy has #{count} polygons")
+  polygons_count += count
+
+  metaltop       = metaltop_drawn + metaltop_dummy
+
+  metaltop_label = get_polygons(53, 10)
+  count = metaltop_label.count
+  logger.info("metaltop_label has #{count} polygons")
+  polygons_count += count
+
+  metaltop_slot = get_polygons(53, 3)
+  count = metaltop_slot.count
+  logger.info("metaltop_slot has #{count} polygons")
+  polygons_count += count
+
+  metaltop_blk = get_polygons(53, 5)
+  count = metaltop_blk.count
+  logger.info("metaltop_blk has #{count} polygons")
+  polygons_count += count
+end
+
+case METAL_LEVEL
+when '2LM'
+  top_via       = via1 if via1_tables.include?(TABLE_NAME)
+  topmin1_via   = contact if contact_tables.include?(TABLE_NAME)
+  top_metal     = metal2
+  topmin1_metal = metal1
+when '3LM'
+  top_via       = via2 if via2_tables.include?(TABLE_NAME)
+  topmin1_via   = via1 if via1_tables.include?(TABLE_NAME)
+  top_metal     = metal3
+  topmin1_metal = metal2
+when '4LM'
+  top_via = via3
+  topmin1_via   = via2 if via2_tables.include?(TABLE_NAME)
+  top_metal     = metal4
+  topmin1_metal = metal3
+when '5LM'
+  top_via       = via4
+  topmin1_via   = via3
+  top_metal     = metal5
+  topmin1_metal = metal4
+when '6LM'
+  top_via       = via5
+  topmin1_via   = via4
+  top_metal     = metaltop
+  topmin1_metal = metal5
+else
+  logger.error("Unknown metal stack #{METAL_LEVEL}")
+  raise
+end
+
+pad = get_polygons(37, 0)
+count = pad.count
+logger.info("pad has #{count} polygons")
+polygons_count += count
+
+ubmpperi = get_polygons(183, 0)
+count = ubmpperi.count
+logger.info("ubmpperi has #{count} polygons")
+polygons_count += count
+
+ubmparray = get_polygons(184, 0)
+count = ubmparray.count
+logger.info("ubmparray has #{count} polygons")
+polygons_count += count
+
+ubmeplate = get_polygons(185, 0)
+count = ubmeplate.count
+logger.info("ubmeplate has #{count} polygons")
+polygons_count += count
+
+metal1_res = get_polygons(110, 11)
+count = metal1_res.count
+logger.info("metal1_res has #{count} polygons")
+polygons_count += count
+
+metal2_res = get_polygons(110, 12)
+count = metal2_res.count
+logger.info("metal2_res has #{count} polygons")
+polygons_count += count
+
+metal3_res = get_polygons(110, 13)
+count = metal3_res.count
+logger.info("metal3_res has #{count} polygons")
+polygons_count += count
+
+metal4_res = get_polygons(110, 14)
+count = metal4_res.count
+logger.info("metal4_res has #{count} polygons")
+polygons_count += count
+
+metal5_res = get_polygons(110, 15)
+count = metal5_res.count
+logger.info("metal5_res has #{count} polygons")
+polygons_count += count
+
+metal6_res = get_polygons(110, 16)
+count = metal6_res.count
+logger.info("metal6_res has #{count} polygons")
+polygons_count += count
+
+pr_bndry = get_polygons(0, 0)
+count = pr_bndry.count
+logger.info("pr_bndry has #{count} polygons")
+polygons_count += count
+
+border = get_polygons(63, 0)
+count = border.count
+logger.info("border has #{count} polygons")
+polygons_count += count
+logger.info("Total no. of polygons in the design is #{polygons_count}")
+
+logger.info('Starting deriving base layers.')