diff --git a/compiler/base/hierarchy_design.py b/compiler/base/hierarchy_design.py
index 271e39b8..28954834 100644
--- a/compiler/base/hierarchy_design.py
+++ b/compiler/base/hierarchy_design.py
@@ -33,7 +33,7 @@ class hierarchy_design(hierarchy_spice.spice, hierarchy_layout.layout):
         lvs_dir = OPTS.openram_tech + lvs_subdir + "/"
 
         if os.path.exists(lvs_dir):
-            self.lvs_file = lvs_dir + name + ".sp"
+            self.lvs_file = lvs_dir + cell_name + ".sp"
         else:
             self.lvs_file = self.sp_file
 
diff --git a/compiler/base/hierarchy_layout.py b/compiler/base/hierarchy_layout.py
index 8d76e2d2..67482f61 100644
--- a/compiler/base/hierarchy_layout.py
+++ b/compiler/base/hierarchy_layout.py
@@ -13,6 +13,7 @@ from tech import drc, GDS
 from tech import layer as techlayer
 from tech import layer_indices
 from tech import layer_stacks
+from tech import preferred_directions
 import os
 from globals import OPTS
 from vector import vector
diff --git a/compiler/custom/dff.py b/compiler/custom/dff.py
index 2336ec74..38e3bd75 100644
--- a/compiler/custom/dff.py
+++ b/compiler/custom/dff.py
@@ -26,14 +26,14 @@ class dff(design.design):
     cell_size_layer = "boundary"
 
     def __init__(self, name="dff"):
-        design.design.__init__(self, name)
+        super().__init__(name)
 
-        (width, height) = utils.get_libcell_size(name,
+        (width, height) = utils.get_libcell_size(self.cell_name,
                                                  GDS["unit"],
                                                  layer[self.cell_size_layer])
 
         pin_map = utils.get_libcell_pins(self.pin_names,
-                                         name,
+                                         self.cell_name,
                                          GDS["unit"])
 
         self.width = width
diff --git a/compiler/custom/inv_dec.py b/compiler/custom/inv_dec.py
index 4fb76f7f..b150a38e 100644
--- a/compiler/custom/inv_dec.py
+++ b/compiler/custom/inv_dec.py
@@ -9,7 +9,6 @@ import design
 from tech import GDS, layer, spice, parameter
 import logical_effort
 import utils
-import debug
 
 
 class inv_dec(design.design):
@@ -22,14 +21,14 @@ class inv_dec(design.design):
     cell_size_layer = "boundary"
 
     def __init__(self, name="inv_dec", height=None):
-        design.design.__init__(self, name)
+        super().__init__(name)
 
-        (width, height) = utils.get_libcell_size(name,
+        (width, height) = utils.get_libcell_size(self.cell_name,
                                                  GDS["unit"],
                                                  layer[self.cell_size_layer])
 
         pin_map = utils.get_libcell_pins(self.pin_names,
-                                         name,
+                                         self.cell_name,
                                          GDS["unit"])
 
         self.width = width
diff --git a/compiler/custom/nand2_dec.py b/compiler/custom/nand2_dec.py
index 8a72bc5d..efec63b6 100644
--- a/compiler/custom/nand2_dec.py
+++ b/compiler/custom/nand2_dec.py
@@ -21,14 +21,14 @@ class nand2_dec(design.design):
     cell_size_layer = "boundary"
 
     def __init__(self, name="nand2_dec", height=None):
-        design.design.__init__(self, name)
+        super().__init__(name)
 
-        (width, height) = utils.get_libcell_size(name,
+        (width, height) = utils.get_libcell_size(self.cell_name,
                                                  GDS["unit"],
                                                  layer[self.cell_size_layer])
 
         pin_map = utils.get_libcell_pins(self.pin_names,
-                                         name,
+                                         self.cell_name,
                                          GDS["unit"])
 
         self.width = width
diff --git a/compiler/custom/nand3_dec.py b/compiler/custom/nand3_dec.py
index 621626fc..3fc2b949 100644
--- a/compiler/custom/nand3_dec.py
+++ b/compiler/custom/nand3_dec.py
@@ -21,14 +21,14 @@ class nand3_dec(design.design):
     cell_size_layer = "boundary"
 
     def __init__(self, name="nand3_dec", height=None):
-        design.design.__init__(self, name)
+        super().__init__(name)
 
-        (width, height) = utils.get_libcell_size(name,
+        (width, height) = utils.get_libcell_size(self.cell_name,
                                                  GDS["unit"],
                                                  layer[self.cell_size_layer])
 
         pin_map = utils.get_libcell_pins(self.pin_names,
-                                         name,
+                                         self.cell_name,
                                          GDS["unit"])
 
         self.width = width
diff --git a/compiler/custom/nand4_dec.py b/compiler/custom/nand4_dec.py
index c63239e8..abcfd2f3 100644
--- a/compiler/custom/nand4_dec.py
+++ b/compiler/custom/nand4_dec.py
@@ -21,14 +21,14 @@ class nand4_dec(design.design):
     cell_size_layer = "boundary"
 
     def __init__(self, name="nand4_dec", height=None):
-        design.design.__init__(self, name)
+        super().__init__(name)
 
-        (width, height) = utils.get_libcell_size(name,
+        (width, height) = utils.get_libcell_size(self.cell_name,
                                                  GDS["unit"],
                                                  layer[self.cell_size_layer])
 
         pin_map = utils.get_libcell_pins(self.pin_names,
-                                         name,
+                                         self.cell_name,
                                          GDS["unit"])
 
         self.width = width
diff --git a/compiler/modules/sense_amp.py b/compiler/custom/sense_amp.py
similarity index 96%
rename from compiler/modules/sense_amp.py
rename to compiler/custom/sense_amp.py
index dac6baac..4e84b7fe 100644
--- a/compiler/modules/sense_amp.py
+++ b/compiler/custom/sense_amp.py
@@ -33,12 +33,12 @@ class sense_amp(design.design):
         super().__init__(name)
         debug.info(2, "Create sense_amp")
 
-        (width, height) = utils.get_libcell_size(name,
+        (width, height) = utils.get_libcell_size(self.cell_name,
                                                  GDS["unit"],
                                                  layer[self.cell_size_layer])
 
         pin_map = utils.get_libcell_pins(self.pin_names,
-                                         name,
+                                         self.cell_name,
                                          GDS["unit"])
 
         self.width = width
diff --git a/compiler/custom/tri_gate.py b/compiler/custom/tri_gate.py
index 81c7816f..476cc886 100644
--- a/compiler/custom/tri_gate.py
+++ b/compiler/custom/tri_gate.py
@@ -28,15 +28,15 @@ class tri_gate(design.design):
         if name=="":
             name = "tri{0}".format(tri_gate.unique_id)
             tri_gate.unique_id += 1
-        design.design.__init__(self, name)
+        super().__init__(self, name)
         debug.info(2, "Create tri_gate")
 
-        (width, height) = utils.get_libcell_size(name,
+        (width, height) = utils.get_libcell_size(self.cell_name,
                                                  GDS["unit"],
                                                  layer[self.cell_size_layer])
 
         pin_map = utils.get_libcell_pins(self.pin_names,
-                                         name,
+                                         self.cell_name,
                                          GDS["unit"])
 
         self.width = width
diff --git a/compiler/custom/write_driver.py b/compiler/custom/write_driver.py
index ca86cf25..41375ab3 100644
--- a/compiler/custom/write_driver.py
+++ b/compiler/custom/write_driver.py
@@ -31,15 +31,15 @@ class write_driver(design.design):
     cell_size_layer = "boundary"
 
     def __init__(self, name):
-        design.design.__init__(self, name)
+        super().__init__(name)
         debug.info(2, "Create write_driver")
 
-        (width, height) = utils.get_libcell_size(name,
+        (width, height) = utils.get_libcell_size(self.cell_name,
                                                  GDS["unit"],
                                                  layer[self.cell_size_layer])
 
         pin_map = utils.get_libcell_pins(self.pin_names,
-                                         name,
+                                         self.cell_name,
                                          GDS["unit"])
 
         self.width = width
diff --git a/compiler/custom/and2_dec.py b/compiler/modules/and2_dec.py
similarity index 100%
rename from compiler/custom/and2_dec.py
rename to compiler/modules/and2_dec.py
diff --git a/compiler/custom/and3_dec.py b/compiler/modules/and3_dec.py
similarity index 100%
rename from compiler/custom/and3_dec.py
rename to compiler/modules/and3_dec.py
diff --git a/compiler/custom/and4_dec.py b/compiler/modules/and4_dec.py
similarity index 100%
rename from compiler/custom/and4_dec.py
rename to compiler/modules/and4_dec.py