diff --git a/src/plugins/streamers/lefdef/db_plugin/extDEFImporter.cc b/src/plugins/streamers/lefdef/db_plugin/dbDEFImporter.cc
similarity index 99%
rename from src/plugins/streamers/lefdef/db_plugin/extDEFImporter.cc
rename to src/plugins/streamers/lefdef/db_plugin/dbDEFImporter.cc
index d80a7e91e..05dec67cd 100644
--- a/src/plugins/streamers/lefdef/db_plugin/extDEFImporter.cc
+++ b/src/plugins/streamers/lefdef/db_plugin/dbDEFImporter.cc
@@ -21,13 +21,13 @@
 */
 
 
-#include "extDEFImporter.h"
+#include "dbDEFImporter.h"
 #include "dbPolygonTools.h"
 #include "tlGlobPattern.h"
 
 #include <cmath>
 
-namespace ext
+namespace db
 {
 
 DEFImporter::DEFImporter ()
diff --git a/src/plugins/streamers/lefdef/db_plugin/extDEFImporter.h b/src/plugins/streamers/lefdef/db_plugin/dbDEFImporter.h
similarity index 94%
rename from src/plugins/streamers/lefdef/db_plugin/extDEFImporter.h
rename to src/plugins/streamers/lefdef/db_plugin/dbDEFImporter.h
index 03ba06eef..ef91e6daf 100644
--- a/src/plugins/streamers/lefdef/db_plugin/extDEFImporter.h
+++ b/src/plugins/streamers/lefdef/db_plugin/dbDEFImporter.h
@@ -22,18 +22,18 @@
 
 
 
-#ifndef HDR_extDEFImporter
-#define HDR_extDEFImporter
+#ifndef HDR_dbDEFImporter
+#define HDR_dbDEFImporter
 
 #include "dbCommon.h"
 #include "dbLayout.h"
 #include "tlStream.h"
-#include "extLEFImporter.h"
+#include "dbLEFImporter.h"
 
 #include <vector>
 #include <string>
 
-namespace ext
+namespace db
 {
 
 /**
diff --git a/src/plugins/streamers/lefdef/db_plugin/extLEFDEFImporter.cc b/src/plugins/streamers/lefdef/db_plugin/dbLEFDEFImporter.cc
similarity index 99%
rename from src/plugins/streamers/lefdef/db_plugin/extLEFDEFImporter.cc
rename to src/plugins/streamers/lefdef/db_plugin/dbLEFDEFImporter.cc
index 51d89c24e..a5474ffc5 100644
--- a/src/plugins/streamers/lefdef/db_plugin/extLEFDEFImporter.cc
+++ b/src/plugins/streamers/lefdef/db_plugin/dbLEFDEFImporter.cc
@@ -21,7 +21,7 @@
 */
 
 
-#include "extLEFDEFImporter.h"
+#include "dbLEFDEFImporter.h"
 
 #include "tlStream.h"
 #include "tlProgress.h"
@@ -30,7 +30,7 @@
 
 #include <QFileInfo>
 
-namespace ext
+namespace db
 {
 
 // -----------------------------------------------------------------------------------
diff --git a/src/plugins/streamers/lefdef/db_plugin/extLEFDEFImporter.h b/src/plugins/streamers/lefdef/db_plugin/dbLEFDEFImporter.h
similarity index 99%
rename from src/plugins/streamers/lefdef/db_plugin/extLEFDEFImporter.h
rename to src/plugins/streamers/lefdef/db_plugin/dbLEFDEFImporter.h
index 1df847718..36c1a6417 100644
--- a/src/plugins/streamers/lefdef/db_plugin/extLEFDEFImporter.h
+++ b/src/plugins/streamers/lefdef/db_plugin/dbLEFDEFImporter.h
@@ -21,8 +21,8 @@
 */
 
 
-#ifndef HDR_extLEFDEFImporter
-#define HDR_extLEFDEFImporter
+#ifndef HDR_dbLEFDEFImporter
+#define HDR_dbLEFDEFImporter
 
 #include "dbCommon.h"
 #include "dbLayout.h"
@@ -40,7 +40,7 @@ namespace tl
   class AbsoluteProgress;
 }
 
-namespace ext
+namespace db
 {
 
 /**
diff --git a/src/plugins/streamers/lefdef/db_plugin/extLEFImporter.cc b/src/plugins/streamers/lefdef/db_plugin/dbLEFImporter.cc
similarity index 99%
rename from src/plugins/streamers/lefdef/db_plugin/extLEFImporter.cc
rename to src/plugins/streamers/lefdef/db_plugin/dbLEFImporter.cc
index dfffb21e4..105ddcc32 100644
--- a/src/plugins/streamers/lefdef/db_plugin/extLEFImporter.cc
+++ b/src/plugins/streamers/lefdef/db_plugin/dbLEFImporter.cc
@@ -21,13 +21,13 @@
 */
 
 
-#include "extLEFImporter.h"
+#include "dbLEFImporter.h"
 
 #include "tlStream.h"
 
 #include <cctype>
 
-namespace ext
+namespace db
 {
 
 // -----------------------------------------------------------------------------------
diff --git a/src/plugins/streamers/lefdef/db_plugin/extLEFImporter.h b/src/plugins/streamers/lefdef/db_plugin/dbLEFImporter.h
similarity index 96%
rename from src/plugins/streamers/lefdef/db_plugin/extLEFImporter.h
rename to src/plugins/streamers/lefdef/db_plugin/dbLEFImporter.h
index 28c8c63fa..85ad7cbed 100644
--- a/src/plugins/streamers/lefdef/db_plugin/extLEFImporter.h
+++ b/src/plugins/streamers/lefdef/db_plugin/dbLEFImporter.h
@@ -22,10 +22,10 @@
 
 
 
-#ifndef HDR_extLEFImporter
-#define HDR_extLEFImporter
+#ifndef HDR_dbLEFImporter
+#define HDR_dbLEFImporter
 
-#include "extLEFDEFImporter.h"
+#include "dbLEFDEFImporter.h"
 
 #include "dbCommon.h"
 #include "dbLayout.h"
@@ -37,7 +37,7 @@
 #include <string>
 #include <map>
 
-namespace ext
+namespace db
 {
 
 /**
diff --git a/src/plugins/streamers/lefdef/db_plugin/db_plugin.pro b/src/plugins/streamers/lefdef/db_plugin/db_plugin.pro
index ac74ca379..5bff78e7b 100644
--- a/src/plugins/streamers/lefdef/db_plugin/db_plugin.pro
+++ b/src/plugins/streamers/lefdef/db_plugin/db_plugin.pro
@@ -5,12 +5,12 @@ DESTDIR = $$OUT_PWD/../../../../db_plugins
 include($$PWD/../../../db_plugin.pri)
 
 HEADERS = \
-  extDEFImporter.h \
-  extLEFImporter.h \
-  extLEFDEFImporter.h \
+    dbDEFImporter.h \
+    dbLEFDEFImporter.h \
+    dbLEFImporter.h
 
 SOURCES = \
-  extDEFImporter.cc \
-  extLEFDEFImporter.cc \
-  extLEFImporter.cc \
   gsiDeclDbLEFDEF.cc \
+    dbDEFImporter.cc \
+    dbLEFDEFImporter.cc \
+    dbLEFImporter.cc
diff --git a/src/plugins/streamers/lefdef/db_plugin/gsiDeclDbLEFDEF.cc b/src/plugins/streamers/lefdef/db_plugin/gsiDeclDbLEFDEF.cc
index d9704180a..7124bc973 100644
--- a/src/plugins/streamers/lefdef/db_plugin/gsiDeclDbLEFDEF.cc
+++ b/src/plugins/streamers/lefdef/db_plugin/gsiDeclDbLEFDEF.cc
@@ -23,9 +23,9 @@
 
 #include "gsiDecl.h"
 
-#include "extLEFImporter.h"
-#include "extDEFImporter.h"
-#include "extLEFDEFImporter.h"
+#include "dbLEFImporter.h"
+#include "dbDEFImporter.h"
+#include "dbLEFDEFImporter.h"
 
 namespace gsi
 {
@@ -33,12 +33,12 @@ namespace gsi
 // ---------------------------------------------------------------
 //  gsi Implementation of specific methods
 
-static ext::LEFDEFReaderOptions &get_lefdef_config (db::LoadLayoutOptions *options)
+static db::LEFDEFReaderOptions &get_lefdef_config (db::LoadLayoutOptions *options)
 {
-  return options->get_options<ext::LEFDEFReaderOptions> ();
+  return options->get_options<db::LEFDEFReaderOptions> ();
 }
 
-static void set_lefdef_config (db::LoadLayoutOptions *options, const ext::LEFDEFReaderOptions &config)
+static void set_lefdef_config (db::LoadLayoutOptions *options, const db::LEFDEFReaderOptions &config)
 {
   options->set_options (config);
 }
@@ -61,7 +61,7 @@ gsi::ClassExt<db::LoadLayoutOptions> decl_ext_lefdef_reader_options (
   )
 );
 
-static tl::Variant get_net_property_name (const ext::LEFDEFReaderOptions *config)
+static tl::Variant get_net_property_name (const db::LEFDEFReaderOptions *config)
 {
   if (config->produce_net_names ()) {
     return config->net_property_name ();
@@ -70,15 +70,15 @@ static tl::Variant get_net_property_name (const ext::LEFDEFReaderOptions *config
   }
 }
 
-static void set_net_property_name (ext::LEFDEFReaderOptions *config, const tl::Variant &name)
+static void set_net_property_name (db::LEFDEFReaderOptions *config, const tl::Variant &name)
 {
   config->set_produce_net_names (! name.is_nil ());
   config->set_net_property_name (name);
 }
 
 static
-gsi::Class<ext::LEFDEFReaderOptions> decl_lefdef_config ("lay", "LEFDEFReaderConfiguration",
-  gsi::method ("layer_map", (db::LayerMap &(ext::LEFDEFReaderOptions::*) ()) &ext::LEFDEFReaderOptions::layer_map,
+gsi::Class<db::LEFDEFReaderOptions> decl_lefdef_config ("lay", "LEFDEFReaderConfiguration",
+  gsi::method ("layer_map", (db::LayerMap &(db::LEFDEFReaderOptions::*) ()) &db::LEFDEFReaderOptions::layer_map,
     "@brief Gets the layer map to be used for the LEF/DEF reader\n"
     "@return A reference to the layer map\n"
     "Because LEF/DEF layer mapping is substantially different than for normal layout files, the LEF/DEF reader "
@@ -89,24 +89,24 @@ gsi::Class<ext::LEFDEFReaderOptions> decl_lefdef_config ("lay", "LEFDEFReaderCon
     "The setter is \\layer_map=. \\create_other_layers= is available to control whether layers "
     "not specified in the layer mapping table shall be created automatically."
   ) +
-  gsi::method ("layer_map=", &ext::LEFDEFReaderOptions::set_layer_map,
+  gsi::method ("layer_map=", &db::LEFDEFReaderOptions::set_layer_map,
     "@brief Sets the layer map to be used for the LEF/DEF reader\n"
     "See \\layer_map for details."
   ) +
-  gsi::method ("create_other_layers", &ext::LEFDEFReaderOptions::read_all_layers,
+  gsi::method ("create_other_layers", &db::LEFDEFReaderOptions::read_all_layers,
     "@brief Gets a value indicating whether layers not mapped in the layer map shall be created too\n"
     "See \\layer_map for details."
   ) +
-  gsi::method ("create_other_layers=", &ext::LEFDEFReaderOptions::set_read_all_layers,
+  gsi::method ("create_other_layers=", &db::LEFDEFReaderOptions::set_read_all_layers,
     "@brief Sets a value indicating whether layers not mapped in the layer map shall be created too\n"
     "See \\layer_map for details."
   ) +
-  gsi::method ("dbu", &ext::LEFDEFReaderOptions::dbu,
+  gsi::method ("dbu", &db::LEFDEFReaderOptions::dbu,
     "@brief Gets the database unit to use for producing the layout.\n"
     "This value specifies the database to be used for the layout that is read. When a DEF file is specified with "
     "a different database unit, the layout is translated into this database unit.\n"
   ) +
-  gsi::method ("dbu=", &ext::LEFDEFReaderOptions::set_dbu, gsi::arg ("dbu"),
+  gsi::method ("dbu=", &db::LEFDEFReaderOptions::set_dbu, gsi::arg ("dbu"),
     "@brief Sets the database unit to use for producing the layout.\n"
     "See \\dbu for details."
   ) +
@@ -122,43 +122,43 @@ gsi::Class<ext::LEFDEFReaderOptions> decl_lefdef_config ("lay", "LEFDEFReaderCon
     "@brief Sets a value indicating whether and how to produce net names as properties.\n"
     "See \\net_property_name for details."
   ) +
-  gsi::method ("produce_cell_outlines", &ext::LEFDEFReaderOptions::produce_cell_outlines,
+  gsi::method ("produce_cell_outlines", &db::LEFDEFReaderOptions::produce_cell_outlines,
     "@brief Gets a value indicating whether to produce cell outlines.\n"
     "If set to true, cell outlines will be produced on the layer given by \\cell_outline_layer. "
   ) +
-  gsi::method ("produce_cell_outlines=", &ext::LEFDEFReaderOptions::set_produce_cell_outlines, gsi::arg ("produce"),
+  gsi::method ("produce_cell_outlines=", &db::LEFDEFReaderOptions::set_produce_cell_outlines, gsi::arg ("produce"),
     "@brief Sets a value indicating whether to produce cell outlines.\n"
     "See \\produce_cell_outlines for details.\n"
   ) +
-  gsi::method ("cell_outline_layer", &ext::LEFDEFReaderOptions::cell_outline_layer,
+  gsi::method ("cell_outline_layer", &db::LEFDEFReaderOptions::cell_outline_layer,
     "@brief Gets the layer on which to produce the cell outline.\n"
     "This attribute is a string correspondig to the string representation of \\LayerInfo. "
     "This string can be either a layer number, a layer/datatype pair, a name or a combination of both. See \\LayerInfo for details.\n"
     "The setter for this attribute is \\cell_outline_layer=. See also \\produce_cell_outlines."
   ) +
-  gsi::method ("cell_outline_layer=", &ext::LEFDEFReaderOptions::set_cell_outline_layer, gsi::arg ("spec"),
+  gsi::method ("cell_outline_layer=", &db::LEFDEFReaderOptions::set_cell_outline_layer, gsi::arg ("spec"),
     "@brief Sets the layer on which to produce the cell outline.\n"
     "See \\cell_outline_layer for details.\n"
   ) +
-  gsi::method ("produce_placement_blockages", &ext::LEFDEFReaderOptions::produce_placement_blockages,
+  gsi::method ("produce_placement_blockages", &db::LEFDEFReaderOptions::produce_placement_blockages,
     "@brief Gets a value indicating whether to produce placement blockage regions.\n"
     "If set to true, polygons will be produced representing the placement blockage region on the layer given by \\placement_blockage_layer. "
   ) +
-  gsi::method ("produce_placement_blockages=", &ext::LEFDEFReaderOptions::set_produce_placement_blockages, gsi::arg ("produce"),
+  gsi::method ("produce_placement_blockages=", &db::LEFDEFReaderOptions::set_produce_placement_blockages, gsi::arg ("produce"),
     "@brief Sets a value indicating whether to produce placement blockage regions.\n"
     "See \\produce_placement_blockages for details.\n"
   ) +
-  gsi::method ("placement_blockage_layer", &ext::LEFDEFReaderOptions::placement_blockage_layer,
+  gsi::method ("placement_blockage_layer", &db::LEFDEFReaderOptions::placement_blockage_layer,
     "@brief Gets the layer on which to produce the placement blockage.\n"
     "This attribute is a string correspondig to the string representation of \\LayerInfo. "
     "This string can be either a layer number, a layer/datatype pair, a name or a combination of both. See \\LayerInfo for details."
     "The setter for this attribute is \\placement_blockage_layer=. See also \\produce_placement_blockages."
   ) +
-  gsi::method ("placement_blockage_layer=", &ext::LEFDEFReaderOptions::set_placement_blockage_layer,
+  gsi::method ("placement_blockage_layer=", &db::LEFDEFReaderOptions::set_placement_blockage_layer,
     "@brief Sets the layer on which to produce the placement blockage.\n"
     "See \\placement_blockage_layer for details.\n"
   ) +
-  gsi::method ("produce_via_geometry", &ext::LEFDEFReaderOptions::produce_via_geometry,
+  gsi::method ("produce_via_geometry", &db::LEFDEFReaderOptions::produce_via_geometry,
     "@brief Sets a value indicating whether via geometries shall be produced.\n"
     "\n"
     "If set to true, shapes will be produced for each via. The layer to be produced will be determined from the "
@@ -178,154 +178,154 @@ gsi::Class<ext::LEFDEFReaderOptions> decl_lefdef_config ("lay", "LEFDEFReaderCon
     "    and the layer name will be 'V1.GEO'. @/ul"
     "@/li\n"
   ) +
-  gsi::method ("produce_via_geometry=", &ext::LEFDEFReaderOptions::set_produce_via_geometry, gsi::arg ("produce"),
+  gsi::method ("produce_via_geometry=", &db::LEFDEFReaderOptions::set_produce_via_geometry, gsi::arg ("produce"),
     "@brief Sets a value indicating whether via geometries shall be produced.\n"
     "See \\produce_via_geometry for details.\n"
   ) +
-  gsi::method ("via_geometry_suffix", &ext::LEFDEFReaderOptions::via_geometry_suffix,
+  gsi::method ("via_geometry_suffix", &db::LEFDEFReaderOptions::via_geometry_suffix,
     "@brief Gets the via geometry layer name suffix.\n"
     "See \\produce_via_geometry for details about this property.\n"
   ) +
-  gsi::method ("via_geometry_suffix=", &ext::LEFDEFReaderOptions::set_via_geometry_suffix, gsi::arg ("suffix"),
+  gsi::method ("via_geometry_suffix=", &db::LEFDEFReaderOptions::set_via_geometry_suffix, gsi::arg ("suffix"),
     "@brief Sets the via geometry layer name suffix.\n"
     "See \\produce_via_geometry for details about this property.\n"
   ) +
-  gsi::method ("via_geometry_datatype", &ext::LEFDEFReaderOptions::via_geometry_datatype,
+  gsi::method ("via_geometry_datatype", &db::LEFDEFReaderOptions::via_geometry_datatype,
     "@brief Gets the via geometry layer datatype value.\n"
     "See \\produce_via_geometry for details about this property.\n"
   ) +
-  gsi::method ("via_geometry_datatype=", &ext::LEFDEFReaderOptions::set_via_geometry_datatype, gsi::arg ("datatype"),
+  gsi::method ("via_geometry_datatype=", &db::LEFDEFReaderOptions::set_via_geometry_datatype, gsi::arg ("datatype"),
     "@brief Sets the via geometry layer datatype value.\n"
     "See \\produce_via_geometry for details about this property.\n"
   ) +
-  gsi::method ("produce_pins", &ext::LEFDEFReaderOptions::produce_pins,
+  gsi::method ("produce_pins", &db::LEFDEFReaderOptions::produce_pins,
     "@brief Gets a value indicating whether pin geometries shall be produced.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("produce_pins=", &ext::LEFDEFReaderOptions::set_produce_pins, gsi::arg ("produce"),
+  gsi::method ("produce_pins=", &db::LEFDEFReaderOptions::set_produce_pins, gsi::arg ("produce"),
     "@brief Sets a value indicating whether pin geometries shall be produced.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("pins_suffix", &ext::LEFDEFReaderOptions::pins_suffix,
+  gsi::method ("pins_suffix", &db::LEFDEFReaderOptions::pins_suffix,
     "@brief Gets the pin geometry layer name suffix.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("pins_suffix=", &ext::LEFDEFReaderOptions::set_pins_suffix, gsi::arg ("suffix"),
+  gsi::method ("pins_suffix=", &db::LEFDEFReaderOptions::set_pins_suffix, gsi::arg ("suffix"),
     "@brief Sets the pin geometry layer name suffix.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("pins_datatype", &ext::LEFDEFReaderOptions::pins_datatype,
+  gsi::method ("pins_datatype", &db::LEFDEFReaderOptions::pins_datatype,
     "@brief Gets the pin geometry layer datatype value.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("pins_datatype=", &ext::LEFDEFReaderOptions::set_pins_datatype, gsi::arg ("datatype"),
+  gsi::method ("pins_datatype=", &db::LEFDEFReaderOptions::set_pins_datatype, gsi::arg ("datatype"),
     "@brief Sets the pin geometry layer datatype value.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("produce_obstructions", &ext::LEFDEFReaderOptions::produce_obstructions,
+  gsi::method ("produce_obstructions", &db::LEFDEFReaderOptions::produce_obstructions,
     "@brief Gets a value indicating whether obstruction markers shall be produced.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("produce_obstructions=", &ext::LEFDEFReaderOptions::set_produce_obstructions, gsi::arg ("produce"),
+  gsi::method ("produce_obstructions=", &db::LEFDEFReaderOptions::set_produce_obstructions, gsi::arg ("produce"),
     "@brief Sets a value indicating whether obstruction markers shall be produced.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("obstructions_suffix", &ext::LEFDEFReaderOptions::obstructions_suffix,
+  gsi::method ("obstructions_suffix", &db::LEFDEFReaderOptions::obstructions_suffix,
     "@brief Gets the obstruction marker layer name suffix.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("obstructions_suffix=", &ext::LEFDEFReaderOptions::set_obstructions_suffix, gsi::arg ("suffix"),
+  gsi::method ("obstructions_suffix=", &db::LEFDEFReaderOptions::set_obstructions_suffix, gsi::arg ("suffix"),
     "@brief Sets the obstruction marker layer name suffix.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("obstructions_datatype", &ext::LEFDEFReaderOptions::obstructions_datatype,
+  gsi::method ("obstructions_datatype", &db::LEFDEFReaderOptions::obstructions_datatype,
     "@brief Gets the obstruction marker layer datatype value.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("obstructions_datatype=", &ext::LEFDEFReaderOptions::set_obstructions_datatype, gsi::arg ("datatype"),
+  gsi::method ("obstructions_datatype=", &db::LEFDEFReaderOptions::set_obstructions_datatype, gsi::arg ("datatype"),
     "@brief Sets the obstruction marker layer datatype value.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("produce_blockages", &ext::LEFDEFReaderOptions::produce_blockages,
+  gsi::method ("produce_blockages", &db::LEFDEFReaderOptions::produce_blockages,
     "@brief Gets a value indicating whether routing blockage markers shall be produced.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("produce_blockages=", &ext::LEFDEFReaderOptions::set_produce_blockages, gsi::arg ("produce"),
+  gsi::method ("produce_blockages=", &db::LEFDEFReaderOptions::set_produce_blockages, gsi::arg ("produce"),
     "@brief Sets a value indicating whether routing blockage markers shall be produced.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("blockages_suffix", &ext::LEFDEFReaderOptions::blockages_suffix,
+  gsi::method ("blockages_suffix", &db::LEFDEFReaderOptions::blockages_suffix,
     "@brief Gets the blockage marker layer name suffix.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("blockages_suffix=", &ext::LEFDEFReaderOptions::set_blockages_suffix, gsi::arg ("suffix"),
+  gsi::method ("blockages_suffix=", &db::LEFDEFReaderOptions::set_blockages_suffix, gsi::arg ("suffix"),
     "@brief Sets the blockage marker layer name suffix.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("blockages_datatype", &ext::LEFDEFReaderOptions::blockages_datatype,
+  gsi::method ("blockages_datatype", &db::LEFDEFReaderOptions::blockages_datatype,
     "@brief Gets the blockage marker layer datatype value.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("blockages_datatype=", &ext::LEFDEFReaderOptions::set_blockages_datatype, gsi::arg ("datatype"),
+  gsi::method ("blockages_datatype=", &db::LEFDEFReaderOptions::set_blockages_datatype, gsi::arg ("datatype"),
     "@brief Sets the blockage marker layer datatype value.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("produce_labels", &ext::LEFDEFReaderOptions::produce_labels,
+  gsi::method ("produce_labels", &db::LEFDEFReaderOptions::produce_labels,
     "@brief Gets a value indicating whether labels shall be produced.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("produce_labels=", &ext::LEFDEFReaderOptions::set_produce_labels, gsi::arg ("produce"),
+  gsi::method ("produce_labels=", &db::LEFDEFReaderOptions::set_produce_labels, gsi::arg ("produce"),
     "@brief Sets a value indicating whether labels shall be produced.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("labels_suffix", &ext::LEFDEFReaderOptions::labels_suffix,
+  gsi::method ("labels_suffix", &db::LEFDEFReaderOptions::labels_suffix,
     "@brief Gets the label layer name suffix.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("labels_suffix=", &ext::LEFDEFReaderOptions::set_labels_suffix, gsi::arg ("suffix"),
+  gsi::method ("labels_suffix=", &db::LEFDEFReaderOptions::set_labels_suffix, gsi::arg ("suffix"),
     "@brief Sets the label layer name suffix.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("labels_datatype", &ext::LEFDEFReaderOptions::labels_datatype,
+  gsi::method ("labels_datatype", &db::LEFDEFReaderOptions::labels_datatype,
     "@brief Gets the labels layer datatype value.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("labels_datatype=", &ext::LEFDEFReaderOptions::set_labels_datatype, gsi::arg ("datatype"),
+  gsi::method ("labels_datatype=", &db::LEFDEFReaderOptions::set_labels_datatype, gsi::arg ("datatype"),
     "@brief Sets the labels layer datatype value.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("produce_routing", &ext::LEFDEFReaderOptions::produce_routing,
+  gsi::method ("produce_routing", &db::LEFDEFReaderOptions::produce_routing,
     "@brief Gets a value indicating whether routing geometry shall be produced.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("produce_routing=", &ext::LEFDEFReaderOptions::set_produce_routing, gsi::arg ("produce"),
+  gsi::method ("produce_routing=", &db::LEFDEFReaderOptions::set_produce_routing, gsi::arg ("produce"),
     "@brief Sets a value indicating whether routing geometry shall be produced.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("routing_suffix", &ext::LEFDEFReaderOptions::routing_suffix,
+  gsi::method ("routing_suffix", &db::LEFDEFReaderOptions::routing_suffix,
     "@brief Gets the routing layer name suffix.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("routing_suffix=", &ext::LEFDEFReaderOptions::set_routing_suffix, gsi::arg ("suffix"),
+  gsi::method ("routing_suffix=", &db::LEFDEFReaderOptions::set_routing_suffix, gsi::arg ("suffix"),
     "@brief Sets the routing layer name suffix.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("routing_datatype", &ext::LEFDEFReaderOptions::routing_datatype,
+  gsi::method ("routing_datatype", &db::LEFDEFReaderOptions::routing_datatype,
     "@brief Gets the routing layer datatype value.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("routing_datatype=", &ext::LEFDEFReaderOptions::set_routing_datatype, gsi::arg ("datatype"),
+  gsi::method ("routing_datatype=", &db::LEFDEFReaderOptions::set_routing_datatype, gsi::arg ("datatype"),
     "@brief Sets the routing layer datatype value.\n"
     "See \\produce_via_geometry for details about the layer production rules."
   ) +
-  gsi::method ("lef_files", &ext::LEFDEFReaderOptions::lef_files,
+  gsi::method ("lef_files", &db::LEFDEFReaderOptions::lef_files,
     "@brief Gets the list technology LEF files to additionally import\n"
     "Returns a list of path names for technology LEF files to read in addition to the primary file. "
     "Relative paths are resolved relative to the file to read.\n"
     "\n"
     "The setter for this property is \\lef_files=."
   ) +
-  gsi::method ("lef_files=", &ext::LEFDEFReaderOptions::set_lef_files,
+  gsi::method ("lef_files=", &db::LEFDEFReaderOptions::set_lef_files,
     "@brief Sets the list technology LEF files to additionally import\n"
     "See \\lef_files for details."
   ),
diff --git a/src/plugins/streamers/lefdef/lay_plugin/extLEFDEFImport.cc b/src/plugins/streamers/lefdef/lay_plugin/layLEFDEFImport.cc
similarity index 87%
rename from src/plugins/streamers/lefdef/lay_plugin/extLEFDEFImport.cc
rename to src/plugins/streamers/lefdef/lay_plugin/layLEFDEFImport.cc
index 064ce64ae..e0e4351e6 100644
--- a/src/plugins/streamers/lefdef/lay_plugin/extLEFDEFImport.cc
+++ b/src/plugins/streamers/lefdef/lay_plugin/layLEFDEFImport.cc
@@ -21,10 +21,10 @@
 */
 
 
-#include "extLEFImporter.h"
-#include "extDEFImporter.h"
-#include "extLEFDEFImportDialogs.h"
+#include "dbLEFImporter.h"
+#include "dbDEFImporter.h"
 
+#include "layLEFDEFImportDialogs.h"
 #include "layPlugin.h"
 #include "layMainWindow.h"
 #include "layFileDialog.h"
@@ -36,7 +36,7 @@
 #include <QFileInfo>
 #include <QApplication>
 
-namespace ext
+namespace lay
 {
 
 // -----------------------------------------------------------------------------------------------
@@ -69,8 +69,8 @@ public:
   virtual void get_menu_entries (std::vector<lay::MenuEntry> &menu_entries) const
   {
     lay::PluginDeclaration::get_menu_entries (menu_entries);
-    menu_entries.push_back (lay::MenuEntry ("ext::import_lef", "import_lef:edit", "file_menu.import_menu.end", tl::to_string (QObject::tr ("LEF"))));
-    menu_entries.push_back (lay::MenuEntry ("ext::import_def", "import_def:edit", "file_menu.import_menu.end", tl::to_string (QObject::tr ("DEF/LEF"))));
+    menu_entries.push_back (lay::MenuEntry ("db::import_lef", "import_lef:edit", "file_menu.import_menu.end", tl::to_string (QObject::tr ("LEF"))));
+    menu_entries.push_back (lay::MenuEntry ("db::import_def", "import_def:edit", "file_menu.import_menu.end", tl::to_string (QObject::tr ("DEF/LEF"))));
   }
 
   virtual bool configure (const std::string &name, const std::string &value)
@@ -93,9 +93,9 @@ public:
 
   virtual bool menu_activated (const std::string &symbol) const
   {
-    if (symbol == "ext::import_lef" || symbol == "ext::import_def") {
+    if (symbol == "db::import_lef" || symbol == "db::import_def") {
 
-      bool import_lef = (symbol == "ext::import_lef");
+      bool import_lef = (symbol == "db::import_lef");
 
       LEFDEFImportData data;
       try {
@@ -132,15 +132,15 @@ public:
           tech_name.clear (); // use default technology
         }
         const lay::Technology *tech = lay::Technologies::instance ()->technology_by_name (tech_name);
-        ext::LEFDEFReaderOptions options;
+        db::LEFDEFReaderOptions options;
         if (tech) {
-          const ext::LEFDEFReaderOptions *tech_options = dynamic_cast<const ext::LEFDEFReaderOptions *>(tech->load_layout_options ().get_options ("LEFDEF"));
+          const db::LEFDEFReaderOptions *tech_options = dynamic_cast<const db::LEFDEFReaderOptions *>(tech->load_layout_options ().get_options ("LEFDEF"));
           if (tech_options) {
             options = *tech_options;
           }
         }
 
-        ext::LEFDEFLayerDelegate layers (&options);
+        db::LEFDEFLayerDelegate layers (&options);
         layers.prepare (*layout);
         layout->dbu (options.dbu ());
 
@@ -148,7 +148,7 @@ public:
 
           tl::SelfTimer timer (tl::verbosity () >= 11, tl::to_string (QObject::tr ("Reading LEF file")));
 
-          ext::LEFImporter importer;
+          db::LEFImporter importer;
 
           for (std::vector<std::string>::const_iterator l = options.begin_lef_files (); l != options.end_lef_files (); ++l) {
             tl::InputStream lef_stream (*l);
@@ -163,7 +163,7 @@ public:
 
           tl::SelfTimer timer (tl::verbosity () >= 11, tl::to_string (QObject::tr ("Reading DEF file")));
 
-          DEFImporter importer;
+          db::DEFImporter importer;
 
           QFileInfo def_fi (tl::to_qstring (data.file));
 
@@ -219,7 +219,7 @@ private:
   std::string m_def_spec;
 };
 
-static tl::RegisteredClass<lay::PluginDeclaration> config_decl (new ext::LEFDEFImportPluginDeclaration (), 1400, "ext::LEFDEFImportPlugin");
+static tl::RegisteredClass<lay::PluginDeclaration> config_decl (new lay::LEFDEFImportPluginDeclaration (), 1400, "db::LEFDEFImportPlugin");
 
 }
 
diff --git a/src/plugins/streamers/lefdef/lay_plugin/extLEFDEFImportDialogs.cc b/src/plugins/streamers/lefdef/lay_plugin/layLEFDEFImportDialogs.cc
similarity index 98%
rename from src/plugins/streamers/lefdef/lay_plugin/extLEFDEFImportDialogs.cc
rename to src/plugins/streamers/lefdef/lay_plugin/layLEFDEFImportDialogs.cc
index 87022aa6d..d28efcdc5 100644
--- a/src/plugins/streamers/lefdef/lay_plugin/extLEFDEFImportDialogs.cc
+++ b/src/plugins/streamers/lefdef/lay_plugin/layLEFDEFImportDialogs.cc
@@ -21,10 +21,11 @@
 */
 
 
-#include "extLEFDEFImportDialogs.h"
-#include "extLEFDEFImporter.h"
+#include "dbLEFDEFImporter.h"
 
 #include "tlExceptions.h"
+
+#include "layLEFDEFImportDialogs.h"
 #include "layLoadLayoutOptionsDialog.h"
 #include "layQtTools.h"
 #include "layMainWindow.h"
@@ -32,7 +33,7 @@
 
 #include <QFileDialog>
 
-namespace ext
+namespace lay
 {
 
 // -----------------------------------------------------------------------------------------------
@@ -366,7 +367,7 @@ LEFDEFReaderOptionsEditor::LEFDEFReaderOptionsEditor (QWidget *parent)
 void 
 LEFDEFReaderOptionsEditor::commit (db::FormatSpecificReaderOptions *options, const lay::Technology * /*tech*/)
 {
-  LEFDEFReaderOptions *data = dynamic_cast<LEFDEFReaderOptions *> (options);
+  db::LEFDEFReaderOptions *data = dynamic_cast<db::LEFDEFReaderOptions *> (options);
   if (! data) {
     return;
   }
@@ -437,8 +438,8 @@ LEFDEFReaderOptionsEditor::commit (db::FormatSpecificReaderOptions *options, con
 void 
 LEFDEFReaderOptionsEditor::setup (const db::FormatSpecificReaderOptions *options, const lay::Technology *tech)
 {
-  static LEFDEFReaderOptions empty;
-  const LEFDEFReaderOptions *data = dynamic_cast<const LEFDEFReaderOptions *> (options);
+  static db::LEFDEFReaderOptions empty;
+  const db::LEFDEFReaderOptions *data = dynamic_cast<const db::LEFDEFReaderOptions *> (options);
   if (! data) {
     data = &empty;
   }
diff --git a/src/plugins/streamers/lefdef/lay_plugin/extLEFDEFImportDialogs.h b/src/plugins/streamers/lefdef/lay_plugin/layLEFDEFImportDialogs.h
similarity index 97%
rename from src/plugins/streamers/lefdef/lay_plugin/extLEFDEFImportDialogs.h
rename to src/plugins/streamers/lefdef/lay_plugin/layLEFDEFImportDialogs.h
index a32bdcdb7..5f5d0cc05 100644
--- a/src/plugins/streamers/lefdef/lay_plugin/extLEFDEFImportDialogs.h
+++ b/src/plugins/streamers/lefdef/lay_plugin/layLEFDEFImportDialogs.h
@@ -21,8 +21,8 @@
 */
 
 
-#ifndef HDR_extLEFImportDialog
-#define HDR_extLEFImportDialog
+#ifndef HDR_dbLEFImportDialog
+#define HDR_dbLEFImportDialog
 
 #include "layCommon.h"
 #include "layTechnology.h"
@@ -33,7 +33,7 @@
 
 #include <QDialog>
 
-namespace ext
+namespace lay
 {
 
 /**
diff --git a/src/plugins/streamers/lefdef/lay_plugin/extLEFDEFPlugin.cc b/src/plugins/streamers/lefdef/lay_plugin/layLEFDEFPlugin.cc
similarity index 96%
rename from src/plugins/streamers/lefdef/lay_plugin/extLEFDEFPlugin.cc
rename to src/plugins/streamers/lefdef/lay_plugin/layLEFDEFPlugin.cc
index 06baedca9..5cb5e0ca5 100644
--- a/src/plugins/streamers/lefdef/lay_plugin/extLEFDEFPlugin.cc
+++ b/src/plugins/streamers/lefdef/lay_plugin/layLEFDEFPlugin.cc
@@ -23,21 +23,23 @@
 
 #include "tlTimer.h"
 #include "tlStream.h"
+
 #include "dbReader.h"
 #include "dbStream.h"
+#include "dbLEFImporter.h"
+#include "dbDEFImporter.h"
+#include "dbLEFDEFImporter.h"
+
 #include "layPlugin.h"
 #include "layStream.h"
-#include "gsiDecl.h"
+#include "layLEFDEFImportDialogs.h"
 
-#include "extLEFDEFImportDialogs.h"
-#include "extLEFImporter.h"
-#include "extDEFImporter.h"
-#include "extLEFDEFImporter.h"
+#include "gsiDecl.h"
 
 #include <QFileInfo>
 #include <QDir>
 
-namespace ext
+namespace db
 {
 
 // ---------------------------------------------------------------
@@ -125,14 +127,14 @@ private:
 
   const db::LayerMap &read_lefdef (db::Layout &layout, const db::LoadLayoutOptions &options, bool import_lef) throw (tl::Exception)
   {
-    const ext::LEFDEFReaderOptions *lefdef_options = dynamic_cast<const ext::LEFDEFReaderOptions *> (options.get_options (format ()));
-    static ext::LEFDEFReaderOptions default_options;
+    const db::LEFDEFReaderOptions *lefdef_options = dynamic_cast<const db::LEFDEFReaderOptions *> (options.get_options (format ()));
+    static db::LEFDEFReaderOptions default_options;
     if (! lefdef_options) {
       lefdef_options = &default_options;
     }
 
     //  Take the layer map and the "read all layers" flag from the reader options - hence we override the
-    ext::LEFDEFLayerDelegate layers (lefdef_options);
+    db::LEFDEFLayerDelegate layers (lefdef_options);
     layers.prepare (layout);
     layout.dbu (lefdef_options->dbu ());
 
@@ -140,7 +142,7 @@ private:
 
       tl::SelfTimer timer (tl::verbosity () >= 11, tl::to_string (QObject::tr ("Reading LEF file")));
 
-      ext::LEFImporter importer;
+      db::LEFImporter importer;
 
       for (std::vector<std::string>::const_iterator l = lefdef_options->begin_lef_files (); l != lefdef_options->end_lef_files (); ++l) {
 
@@ -255,7 +257,7 @@ public:
 
   lay::StreamReaderOptionsPage *format_specific_options_page (QWidget *parent) const
   {
-    return new LEFDEFReaderOptionsEditor (parent);
+    return new lay::LEFDEFReaderOptionsEditor (parent);
   }
 
   db::FormatSpecificReaderOptions *create_specific_options () const
diff --git a/src/plugins/streamers/lefdef/lay_plugin/lay_plugin.pro b/src/plugins/streamers/lefdef/lay_plugin/lay_plugin.pro
index 51b4fef76..c38a954f5 100644
--- a/src/plugins/streamers/lefdef/lay_plugin/lay_plugin.pro
+++ b/src/plugins/streamers/lefdef/lay_plugin/lay_plugin.pro
@@ -13,12 +13,12 @@ LIBS += -L$$DESTDIR/../db_plugins -llefdef
 }
 
 HEADERS = \
-  extLEFDEFImportDialogs.h \
+    layLEFDEFImportDialogs.h
 
 SOURCES = \
-  extLEFDEFImport.cc \
-  extLEFDEFImportDialogs.cc \
-  extLEFDEFPlugin.cc \
+    layLEFDEFPlugin.cc \
+    layLEFDEFImportDialogs.cc \
+    layLEFDEFImport.cc
 
 FORMS = \
   LEFDEFImportOptionsDialog.ui \
diff --git a/src/plugins/streamers/lefdef/unit_tests/extLEFDEFImport.cc b/src/plugins/streamers/lefdef/unit_tests/dbLEFDEFImport.cc
similarity index 97%
rename from src/plugins/streamers/lefdef/unit_tests/extLEFDEFImport.cc
rename to src/plugins/streamers/lefdef/unit_tests/dbLEFDEFImport.cc
index 776bed2df..ad7cc7e81 100644
--- a/src/plugins/streamers/lefdef/unit_tests/extLEFDEFImport.cc
+++ b/src/plugins/streamers/lefdef/unit_tests/dbLEFDEFImport.cc
@@ -23,8 +23,8 @@
 
 #include "dbLayoutDiff.h"
 #include "dbWriter.h"
-#include "extDEFImporter.h"
-#include "extLEFImporter.h"
+#include "dbDEFImporter.h"
+#include "dbLEFImporter.h"
 
 #include "tlUnitTest.h"
 
@@ -33,7 +33,7 @@
 
 static void run_test (tl::TestBase *_this, const char *lef_dir, const char *filename, const char *au)
 {
-  ext::LEFDEFReaderOptions tc;
+  db::LEFDEFReaderOptions tc;
   tc.set_via_geometry_datatype (0);
   tc.set_via_geometry_suffix ("");
   tc.set_pins_datatype (2);
@@ -46,7 +46,7 @@ static void run_test (tl::TestBase *_this, const char *lef_dir, const char *file
   tc.set_labels_suffix (".LABEL");
   tc.set_blockages_datatype (4);
   tc.set_blockages_suffix (".BLK");
-  ext::LEFDEFLayerDelegate ld (&tc);
+  db::LEFDEFLayerDelegate ld (&tc);
 
   db::Manager m;
   db::Layout layout (&m), layout2 (&m), layout_au (&m);
@@ -55,7 +55,7 @@ static void run_test (tl::TestBase *_this, const char *lef_dir, const char *file
 
   ld.prepare (layout);
 
-  ext::DEFImporter imp;
+  db::DEFImporter imp;
 
   while (! ex.at_end ()) {
 
diff --git a/src/plugins/streamers/lefdef/unit_tests/unit_tests.pro b/src/plugins/streamers/lefdef/unit_tests/unit_tests.pro
index 66019a3a8..5987edb48 100644
--- a/src/plugins/streamers/lefdef/unit_tests/unit_tests.pro
+++ b/src/plugins/streamers/lefdef/unit_tests/unit_tests.pro
@@ -6,7 +6,7 @@ TARGET = lefdef_tests
 include($$PWD/../../../../lib_ut.pri)
 
 SOURCES = \
-  extLEFDEFImport.cc \
+    dbLEFDEFImport.cc
 
 INCLUDEPATH += $$LAY_INC $$TL_INC $$DB_INC $$GSI_INC $$PWD/../db_plugin
 DEPENDPATH += $$LAY_INC $$TL_INC $$DB_INC $$GSI_INC $$PWD/../db_plugin
diff --git a/src/plugins/streamers/pcb/db_plugin/extGerberDrillFileReader.cc b/src/plugins/streamers/pcb/db_plugin/dbGerberDrillFileReader.cc
similarity index 99%
rename from src/plugins/streamers/pcb/db_plugin/extGerberDrillFileReader.cc
rename to src/plugins/streamers/pcb/db_plugin/dbGerberDrillFileReader.cc
index 486adcedc..de3dfc71e 100644
--- a/src/plugins/streamers/pcb/db_plugin/extGerberDrillFileReader.cc
+++ b/src/plugins/streamers/pcb/db_plugin/dbGerberDrillFileReader.cc
@@ -21,9 +21,9 @@
 */
 
 
-#include "extGerberDrillFileReader.h"
+#include "dbGerberDrillFileReader.h"
 
-namespace ext
+namespace db
 {
 
 // ---------------------------------------------------------------------------------
diff --git a/src/plugins/streamers/pcb/db_plugin/extGerberDrillFileReader.h b/src/plugins/streamers/pcb/db_plugin/dbGerberDrillFileReader.h
similarity index 96%
rename from src/plugins/streamers/pcb/db_plugin/extGerberDrillFileReader.h
rename to src/plugins/streamers/pcb/db_plugin/dbGerberDrillFileReader.h
index 66ba9a1cc..8e68a43aa 100644
--- a/src/plugins/streamers/pcb/db_plugin/extGerberDrillFileReader.h
+++ b/src/plugins/streamers/pcb/db_plugin/dbGerberDrillFileReader.h
@@ -21,8 +21,8 @@
 */
 
 
-#ifndef HDR_extGerberDrillFileReader
-#define HDR_extGerberDrillFileReader
+#ifndef HDR_dbGerberDrillFileReader
+#define HDR_dbGerberDrillFileReader
 
 #include "tlStream.h"
 #include "tlString.h"
@@ -30,13 +30,13 @@
 #include "dbTrans.h"
 #include "dbPolygon.h"
 #include "dbEdgeProcessor.h"
-#include "extGerberImporter.h"
+#include "dbGerberImporter.h"
 
 #include <string>
 #include <map>
 #include <vector>
 
-namespace ext
+namespace db
 {
 
 struct DrillHoleDescriptor
diff --git a/src/plugins/streamers/pcb/db_plugin/extGerberImporter.cc b/src/plugins/streamers/pcb/db_plugin/dbGerberImporter.cc
similarity index 96%
rename from src/plugins/streamers/pcb/db_plugin/extGerberImporter.cc
rename to src/plugins/streamers/pcb/db_plugin/dbGerberImporter.cc
index e30c8c210..46b4067fa 100644
--- a/src/plugins/streamers/pcb/db_plugin/extGerberImporter.cc
+++ b/src/plugins/streamers/pcb/db_plugin/dbGerberImporter.cc
@@ -21,9 +21,9 @@
 */
 
 
-#include "extGerberImporter.h"
-#include "extGerberDrillFileReader.h"
-#include "extRS274XReader.h"
+#include "dbGerberImporter.h"
+#include "dbGerberDrillFileReader.h"
+#include "dbRS274XReader.h"
 #include "tlStream.h"
 #include "tlString.h"
 #include "tlString.h"
@@ -35,7 +35,7 @@
 #include <cmath>
 #include <cctype>
 
-namespace ext
+namespace db
 {
 
 // ---------------------------------------------------------------------------------------
@@ -517,11 +517,11 @@ GerberFile::layers_string () const
 //  Implementation of GerberImporter
 
 //  TODO: generalize this:
-std::vector <tl::shared_ptr<ext::GerberFileReader> > get_readers ()
+std::vector <tl::shared_ptr<db::GerberFileReader> > get_readers ()
 {
-  std::vector <tl::shared_ptr<ext::GerberFileReader> > readers;
-  readers.push_back (new ext::GerberDrillFileReader ());
-  readers.push_back (new ext::RS274XReader ());
+  std::vector <tl::shared_ptr<db::GerberFileReader> > readers;
+  readers.push_back (new db::GerberDrillFileReader ());
+  readers.push_back (new db::RS274XReader ());
   return readers;
 }
 
@@ -570,10 +570,10 @@ GerberImporter::scan (tl::TextInputStream &stream)
 {
   try {
 
-    std::vector <tl::shared_ptr<ext::GerberFileReader> > readers = get_readers ();
+    std::vector <tl::shared_ptr<db::GerberFileReader> > readers = get_readers ();
 
     //  determine the reader to use:
-    for (std::vector <tl::shared_ptr<ext::GerberFileReader> >::iterator r = readers.begin (); r != readers.end (); ++r) {
+    for (std::vector <tl::shared_ptr<db::GerberFileReader> >::iterator r = readers.begin (); r != readers.end (); ++r) {
       stream.reset ();
       if ((*r)->accepts (stream)) {
         return (*r)->scan (stream);
@@ -746,7 +746,7 @@ GerberImporter::do_load_project (tl::TextInputStream &stream)
 
       l.test ("file");
 
-      ext::GerberFile file;
+      db::GerberFile file;
 
       std::string fn;
       l.read_word_or_quoted (fn, "%!.:/\\+-,=_$");
@@ -840,7 +840,7 @@ GerberImporter::save_project (std::ostream &stream)
     stream << "layer-styles=" << tl::to_quoted_string (m_layer_styles) << std::endl;
   }
 
-  for (std::vector<ext::GerberFile>::iterator file = m_files.begin (); file != m_files.end (); ++file) {
+  for (std::vector<db::GerberFile>::iterator file = m_files.begin (); file != m_files.end (); ++file) {
 
     stream << "file " << tl::to_quoted_string (file->filename ());
     for (std::vector <db::LayerProperties>::const_iterator ls = file->layer_specs ().begin (); ls != file->layer_specs ().end (); ++ls) {
@@ -959,7 +959,7 @@ GerberImporter::do_read (db::Layout &layout, db::cell_index_type cell_index)
 
     std::string format (m_format_string);
 
-    for (std::vector<ext::GerberFile>::iterator file = m_files.begin (); file != m_files.end (); ++file) {
+    for (std::vector<db::GerberFile>::iterator file = m_files.begin (); file != m_files.end (); ++file) {
 
       ++progress;
 
@@ -987,11 +987,11 @@ GerberImporter::do_read (db::Layout &layout, db::cell_index_type cell_index)
       tl::InputStream input_file (tl::to_string (fi.absoluteFilePath ()));
       tl::TextInputStream stream (input_file);
 
-      std::vector <tl::shared_ptr<ext::GerberFileReader> > readers = get_readers ();
+      std::vector <tl::shared_ptr<db::GerberFileReader> > readers = get_readers ();
 
       //  determine the reader to use:
-      ext::GerberFileReader *reader = 0;
-      for (std::vector <tl::shared_ptr<ext::GerberFileReader> >::iterator r = readers.begin (); r != readers.end (); ++r) {
+      db::GerberFileReader *reader = 0;
+      for (std::vector <tl::shared_ptr<db::GerberFileReader> >::iterator r = readers.begin (); r != readers.end (); ++r) {
         stream.reset ();
         if ((*r)->accepts (stream)) {
           reader = r->operator-> ();
diff --git a/src/plugins/streamers/pcb/db_plugin/extGerberImporter.h b/src/plugins/streamers/pcb/db_plugin/dbGerberImporter.h
similarity index 98%
rename from src/plugins/streamers/pcb/db_plugin/extGerberImporter.h
rename to src/plugins/streamers/pcb/db_plugin/dbGerberImporter.h
index 49bc0441f..d8a613e86 100644
--- a/src/plugins/streamers/pcb/db_plugin/extGerberImporter.h
+++ b/src/plugins/streamers/pcb/db_plugin/dbGerberImporter.h
@@ -21,8 +21,8 @@
 */
 
 
-#ifndef HDR_extGerberImporter
-#define HDR_extGerberImporter
+#ifndef HDR_dbGerberImporter
+#define HDR_dbGerberImporter
 
 #include "dbCommon.h"
 
@@ -45,7 +45,7 @@ namespace lay
   class LayoutView;
 }
 
-namespace ext
+namespace db
 {
 
 /**
@@ -1016,7 +1016,7 @@ public:
   /**
    *  @brief Add a file specification
    */
-  void add_file (const ext::GerberFile &file)
+  void add_file (const db::GerberFile &file)
   {
     m_files.push_back (file);
   }
@@ -1024,7 +1024,7 @@ public:
   /**
    *  @brief Get the files: begin iterator
    */
-  std::vector<ext::GerberFile>::const_iterator begin_files () const
+  std::vector<db::GerberFile>::const_iterator begin_files () const
   {
     return m_files.begin ();
   }
@@ -1032,7 +1032,7 @@ public:
   /**
    *  @brief Get the files: end iterator
    */
-  std::vector<ext::GerberFile>::const_iterator end_files () const
+  std::vector<db::GerberFile>::const_iterator end_files () const
   {
     return m_files.end ();
   }
@@ -1049,7 +1049,7 @@ private:
   std::string m_dir;
   db::DCplxTrans m_global_trans;
   std::vector <std::pair <db::DPoint, db::DPoint> > m_reference_points;
-  std::vector <ext::GerberFile> m_files;
+  std::vector <db::GerberFile> m_files;
 
   void do_read (db::Layout &layout, db::cell_index_type cell_index);
   void do_load_project (tl::TextInputStream &stream);
diff --git a/src/plugins/streamers/pcb/db_plugin/extRS274XApertures.cc b/src/plugins/streamers/pcb/db_plugin/dbRS274XApertures.cc
similarity index 98%
rename from src/plugins/streamers/pcb/db_plugin/extRS274XApertures.cc
rename to src/plugins/streamers/pcb/db_plugin/dbRS274XApertures.cc
index d232293c9..5ade51a96 100644
--- a/src/plugins/streamers/pcb/db_plugin/extRS274XApertures.cc
+++ b/src/plugins/streamers/pcb/db_plugin/dbRS274XApertures.cc
@@ -21,11 +21,11 @@
 */
 
 
-#include "extRS274XApertures.h"
-#include "extRS274XReader.h"
+#include "dbRS274XApertures.h"
+#include "dbRS274XReader.h"
 #include "dbPolygonTools.h"
 
-namespace ext
+namespace db
 {
 
 // -----------------------------------------------------------------------------
@@ -320,7 +320,7 @@ RS274XCircleAperture::do_produce_linear (const db::DPoint &from, const db::DPoin
 // -----------------------------------------------------------------------------
 //  RS274XRectAperture implementation
 
-RS274XRectAperture::RS274XRectAperture (ext::RS274XReader &reader, tl::Extractor &ex)
+RS274XRectAperture::RS274XRectAperture (db::RS274XReader &reader, tl::Extractor &ex)
   : m_dx (0.0), m_dy (0.0), m_hx (0.0), m_hy (0.0)
 {
   ex.expect(",");
@@ -378,7 +378,7 @@ RS274XRectAperture::do_produce_linear (const db::DPoint & /*from*/, const db::DP
 // -----------------------------------------------------------------------------
 //  RS274XOvalAperture implementation
 
-RS274XOvalAperture::RS274XOvalAperture (ext::RS274XReader &reader, tl::Extractor &ex)
+RS274XOvalAperture::RS274XOvalAperture (db::RS274XReader &reader, tl::Extractor &ex)
   : m_dx (0.0), m_dy (0.0), m_hx (0.0), m_hy (0.0)
 {
   ex.expect(",");
@@ -479,7 +479,7 @@ RS274XOvalAperture::do_produce_linear (const db::DPoint & /*from*/, const db::DP
 // -----------------------------------------------------------------------------
 //  RS274XRegularAperture implementation
 
-RS274XRegularAperture::RS274XRegularAperture (ext::RS274XReader &reader, tl::Extractor &ex)
+RS274XRegularAperture::RS274XRegularAperture (db::RS274XReader &reader, tl::Extractor &ex)
   : m_d (0.0), m_a (0.0), m_nsides (0), m_hx (0.0), m_hy (0.0)
 {
   ex.expect(",");
@@ -581,7 +581,7 @@ RS274XRegionAperture::do_produce_linear (const db::DPoint & /*from*/, const db::
 // -----------------------------------------------------------------------------
 //  RS274XMacroAperture implementation
 
-RS274XMacroAperture::RS274XMacroAperture (ext::RS274XReader &reader, const std::string &name, const std::string &def, tl::Extractor &ex)
+RS274XMacroAperture::RS274XMacroAperture (db::RS274XReader &reader, const std::string &name, const std::string &def, tl::Extractor &ex)
   : m_name (name), m_def (def), m_unit (1.0)
 { 
   //  use the unit at definition time, not at execution time
diff --git a/src/plugins/streamers/pcb/db_plugin/extRS274XApertures.h b/src/plugins/streamers/pcb/db_plugin/dbRS274XApertures.h
similarity index 98%
rename from src/plugins/streamers/pcb/db_plugin/extRS274XApertures.h
rename to src/plugins/streamers/pcb/db_plugin/dbRS274XApertures.h
index 78fa02ac6..e97e28ab7 100644
--- a/src/plugins/streamers/pcb/db_plugin/extRS274XApertures.h
+++ b/src/plugins/streamers/pcb/db_plugin/dbRS274XApertures.h
@@ -21,8 +21,8 @@
 */
 
 
-#ifndef HDR_extRS274XApertures
-#define HDR_extRS274XApertures
+#ifndef HDR_dbRS274XApertures
+#define HDR_dbRS274XApertures
 
 #include "dbPoint.h"
 #include "dbPath.h"
@@ -38,7 +38,7 @@ namespace db
   class EdgeProcessor;
 }
  
-namespace ext
+namespace db
 {
 
 class RS274XReader;
diff --git a/src/plugins/streamers/pcb/db_plugin/extRS274XReader.cc b/src/plugins/streamers/pcb/db_plugin/dbRS274XReader.cc
similarity index 99%
rename from src/plugins/streamers/pcb/db_plugin/extRS274XReader.cc
rename to src/plugins/streamers/pcb/db_plugin/dbRS274XReader.cc
index 3e65ec57a..85ee61fec 100644
--- a/src/plugins/streamers/pcb/db_plugin/extRS274XReader.cc
+++ b/src/plugins/streamers/pcb/db_plugin/dbRS274XReader.cc
@@ -21,10 +21,10 @@
 */
 
 
-#include "extRS274XReader.h"
-#include "extRS274XApertures.h"
+#include "dbRS274XReader.h"
+#include "dbRS274XApertures.h"
 
-namespace ext
+namespace db
 {
 
 // ---------------------------------------------------------------------------------
diff --git a/src/plugins/streamers/pcb/db_plugin/extRS274XReader.h b/src/plugins/streamers/pcb/db_plugin/dbRS274XReader.h
similarity index 97%
rename from src/plugins/streamers/pcb/db_plugin/extRS274XReader.h
rename to src/plugins/streamers/pcb/db_plugin/dbRS274XReader.h
index f533a6368..aff726cf3 100644
--- a/src/plugins/streamers/pcb/db_plugin/extRS274XReader.h
+++ b/src/plugins/streamers/pcb/db_plugin/dbRS274XReader.h
@@ -21,8 +21,8 @@
 */
 
 
-#ifndef HDR_extRS274XReader
-#define HDR_extRS274XReader
+#ifndef HDR_dbRS274XReader
+#define HDR_dbRS274XReader
 
 #include "tlStream.h"
 #include "tlString.h"
@@ -30,13 +30,13 @@
 #include "dbTrans.h"
 #include "dbPolygon.h"
 #include "dbEdgeProcessor.h"
-#include "extGerberImporter.h"
+#include "dbGerberImporter.h"
 
 #include <string>
 #include <map>
 #include <vector>
 
-namespace ext
+namespace db
 {
 
 // ---------------------------------------------------------------------------------
diff --git a/src/plugins/streamers/pcb/db_plugin/db_plugin.pro b/src/plugins/streamers/pcb/db_plugin/db_plugin.pro
index 7c814d5ec..b80245675 100644
--- a/src/plugins/streamers/pcb/db_plugin/db_plugin.pro
+++ b/src/plugins/streamers/pcb/db_plugin/db_plugin.pro
@@ -5,13 +5,13 @@ DESTDIR = $$OUT_PWD/../../../../db_plugins
 include($$PWD/../../../db_plugin.pri)
 
 HEADERS = \
-  extGerberDrillFileReader.h \
-  extGerberImporter.h \
-  extRS274XApertures.h \
-  extRS274XReader.h \
+    dbGerberDrillFileReader.h \
+    dbGerberImporter.h \
+    dbRS274XApertures.h \
+    dbRS274XReader.h
 
 SOURCES = \
-  extGerberDrillFileReader.cc \
-  extGerberImporter.cc \
-  extRS274XApertures.cc \
-  extRS274XReader.cc \
+    dbGerberDrillFileReader.cc \
+    dbGerberImporter.cc \
+    dbRS274XApertures.cc \
+    dbRS274XReader.cc
diff --git a/src/plugins/streamers/pcb/lay_plugin/extGerberImport.cc b/src/plugins/streamers/pcb/lay_plugin/layGerberImport.cc
similarity index 80%
rename from src/plugins/streamers/pcb/lay_plugin/extGerberImport.cc
rename to src/plugins/streamers/pcb/lay_plugin/layGerberImport.cc
index 1e3be1650..57c54b3ae 100644
--- a/src/plugins/streamers/pcb/lay_plugin/extGerberImport.cc
+++ b/src/plugins/streamers/pcb/lay_plugin/layGerberImport.cc
@@ -21,12 +21,12 @@
 */
 
 
-#include "extGerberImporter.h"
-#include "extGerberImportDialog.h"
-#include "extRS274XReader.h"
+#include "dbGerberImporter.h"
+#include "dbRS274XReader.h"
 
 #include "dbStream.h"
 
+#include "layGerberImportDialog.h"
 #include "layPlugin.h"
 #include "layFileDialog.h"
 #include "layMainWindow.h"
@@ -35,7 +35,7 @@
 
 #include <QApplication>
 
-namespace ext
+namespace lay
 {
 
 static const std::string cfg_pcb_import_spec ("pcb-import-spec");
@@ -63,11 +63,11 @@ public:
   virtual void get_menu_entries (std::vector<lay::MenuEntry> &menu_entries) const
   {
     lay::PluginDeclaration::get_menu_entries (menu_entries);
-    menu_entries.push_back (lay::MenuEntry ("ext::import_gerber", "import_gerber_menu:edit", "file_menu.import_menu.end", tl::to_string (QObject::tr ("Gerber PCB")), true));
-    menu_entries.push_back (lay::MenuEntry ("ext::import_gerber_new", "import_gerber_new:edit", "file_menu.import_menu.import_gerber_menu.end", tl::to_string (QObject::tr ("New Project"))));
-    menu_entries.push_back (lay::MenuEntry ("ext::import_gerber_new_free", "import_gerber_new_free:edit", "file_menu.import_menu.import_gerber_menu.end", tl::to_string (QObject::tr ("New Project - Free Layer Mapping"))));
-    menu_entries.push_back (lay::MenuEntry ("ext::import_gerber_open", "import_gerber_open:edit", "file_menu.import_menu.import_gerber_menu.end", tl::to_string (QObject::tr ("Open Project"))));
-    menu_entries.push_back (lay::MenuEntry ("ext::import_gerber_recent", "import_gerber_recent:edit", "file_menu.import_menu.import_gerber_menu.end", tl::to_string (QObject::tr ("Recent Project"))));
+    menu_entries.push_back (lay::MenuEntry ("db::import_gerber", "import_gerber_menu:edit", "file_menu.import_menu.end", tl::to_string (QObject::tr ("Gerber PCB")), true));
+    menu_entries.push_back (lay::MenuEntry ("db::import_gerber_new", "import_gerber_new:edit", "file_menu.import_menu.import_gerber_menu.end", tl::to_string (QObject::tr ("New Project"))));
+    menu_entries.push_back (lay::MenuEntry ("db::import_gerber_new_free", "import_gerber_new_free:edit", "file_menu.import_menu.import_gerber_menu.end", tl::to_string (QObject::tr ("New Project - Free Layer Mapping"))));
+    menu_entries.push_back (lay::MenuEntry ("db::import_gerber_open", "import_gerber_open:edit", "file_menu.import_menu.import_gerber_menu.end", tl::to_string (QObject::tr ("Open Project"))));
+    menu_entries.push_back (lay::MenuEntry ("db::import_gerber_recent", "import_gerber_recent:edit", "file_menu.import_menu.import_gerber_menu.end", tl::to_string (QObject::tr ("Recent Project"))));
   }
 
   virtual bool configure (const std::string &name, const std::string &value)
@@ -87,10 +87,10 @@ public:
 
   virtual bool menu_activated (const std::string &symbol) const
   {
-    if (symbol == "ext::import_gerber_recent" || 
-        symbol == "ext::import_gerber_new_free" ||
-        symbol == "ext::import_gerber_new" ||
-        symbol == "ext::import_gerber_open") {
+    if (symbol == "db::import_gerber_recent" ||
+        symbol == "db::import_gerber_new_free" ||
+        symbol == "db::import_gerber_new" ||
+        symbol == "db::import_gerber_open") {
 
       GerberImportData data;
       try {
@@ -99,17 +99,17 @@ public:
         data = GerberImportData ();
       }
 
-      if (symbol == "ext::import_gerber_new_free") {
+      if (symbol == "db::import_gerber_new_free") {
 
         data.reset ();
         data.free_layer_mapping = true;
 
-      } else if (symbol == "ext::import_gerber_new") {
+      } else if (symbol == "db::import_gerber_new") {
 
         data.reset ();
         data.free_layer_mapping = false;
 
-      } else if (symbol == "ext::import_gerber_open") {
+      } else if (symbol == "db::import_gerber_open") {
 
         //  Get the name of the file to open
         lay::FileDialog open_dialog (QApplication::activeWindow (), tl::to_string (QObject::tr ("Gerber Import Project File")), tl::to_string (QObject::tr ("PCB project file (*.pcb);;All files (*)")));
@@ -128,7 +128,7 @@ public:
       lay::PluginRoot *config_root = lay::PluginRoot::instance ();
 
       GerberImportDialog dialog (QApplication::activeWindow (), &data);
-      ext::GerberImporter importer;
+      db::GerberImporter importer;
 
       bool ok = false;
       while (! ok && dialog.exec ()) {
@@ -146,8 +146,8 @@ public:
         config_root->config_end ();
 
         //  TODO: discard layout when an error occurs
-        if (data.mode != ext::GerberImportData::ModeIntoLayout) {
-          lay::MainWindow::instance ()->create_layout (data.mode == ext::GerberImportData::ModeSamePanel ? 2 : 1);
+        if (data.mode != lay::GerberImportData::ModeIntoLayout) {
+          lay::MainWindow::instance ()->create_layout (data.mode == lay::GerberImportData::ModeSamePanel ? 2 : 1);
         }
 
         lay::LayoutView *view = lay::LayoutView::current ();
@@ -156,7 +156,7 @@ public:
 
         std::string lyp_file = data.get_layer_properties_file ();
 
-        if (data.mode == ext::GerberImportData::ModeIntoLayout) {
+        if (data.mode == lay::GerberImportData::ModeIntoLayout) {
 
           importer.read (cv->layout (), cv.cell_index ());
           view->create_initial_layer_props (cv_index, lyp_file, true /*add missing*/);
@@ -189,7 +189,7 @@ private:
   std::string m_import_spec;
 };
 
-static tl::RegisteredClass<lay::PluginDeclaration> config_decl (new ext::GerberImportPluginDeclaration (), 1200, "ext::GerberImportPlugin");
+static tl::RegisteredClass<lay::PluginDeclaration> config_decl (new lay::GerberImportPluginDeclaration (), 1200, "db::GerberImportPlugin");
 
 // ---------------------------------------------------------------
 //  Plugin for the stream reader
@@ -229,7 +229,7 @@ public:
 
     data.load (m_stream);
 
-    ext::GerberImporter importer;
+    db::GerberImporter importer;
     data.setup_importer (&importer);
 
     importer.read (layout);
diff --git a/src/plugins/streamers/pcb/lay_plugin/extGerberImportDialog.cc b/src/plugins/streamers/pcb/lay_plugin/layGerberImportDialog.cc
similarity index 98%
rename from src/plugins/streamers/pcb/lay_plugin/extGerberImportDialog.cc
rename to src/plugins/streamers/pcb/lay_plugin/layGerberImportDialog.cc
index 8828a8301..85ca76cb9 100644
--- a/src/plugins/streamers/pcb/lay_plugin/extGerberImportDialog.cc
+++ b/src/plugins/streamers/pcb/lay_plugin/layGerberImportDialog.cc
@@ -22,12 +22,12 @@
 
 
 #include "ui_GerberImportDialog.h"
-#include "extGerberImporter.h"
-#include "extGerberImportDialog.h"
+#include "dbGerberImporter.h"
 
 #include "layFileDialog.h"
 #include "layDialogs.h"
 #include "layConverters.h"
+#include "layGerberImportDialog.h"
 
 #include "tlExceptions.h"
 #include "tlXMLParser.h"
@@ -39,7 +39,7 @@
 
 #include <fstream>
 
-namespace ext
+namespace lay
 {
 
 // -----------------------------------------------------------------------------------------
@@ -86,7 +86,7 @@ GerberImportData::get_layer_properties_file () const
 }
 
 void 
-GerberImportData::setup_importer (GerberImporter *importer)
+GerberImportData::setup_importer (db::GerberImporter *importer)
 {
   if (num_circle_points >= 4) {
     importer->set_circle_points (num_circle_points);
@@ -107,7 +107,7 @@ GerberImportData::setup_importer (GerberImporter *importer)
 
       if (! file->filename.empty ()) {
 
-        GerberFile file_spec;
+        db::GerberFile file_spec;
         file_spec.set_filename (file->filename);
 
         for (std::vector <int>::const_iterator i = file->layout_layers.begin (); i != file->layout_layers.end (); ++i) {
@@ -136,7 +136,7 @@ GerberImportData::setup_importer (GerberImporter *importer)
         }
 
         if (n * 2 < layout_layers.size ()) {
-          GerberFile file_spec;
+          db::GerberFile file_spec;
           file_spec.set_filename (file->filename);
           file_spec.add_layer_spec (layout_layers [n * 2]);
           importer->add_file (file_spec);
@@ -159,7 +159,7 @@ GerberImportData::setup_importer (GerberImporter *importer)
           nstart = std::distance (artwork_files.begin () + file->stop, artwork_files.end ()) - 1;
         }
 
-        GerberFile file_spec;
+        db::GerberFile file_spec;
         file_spec.set_filename (file->filename);
 
         for (size_t n = nstart; n < nstop; ++n) {
@@ -343,7 +343,7 @@ GerberImportData::from_string (const std::string &s)
       artwork_files.clear ();
       while (! ex.test (";") && ! ex.at_end ()) {
         ex.test ("(");
-        artwork_files.push_back (ext::GerberArtworkFileDescriptor ());
+        artwork_files.push_back (lay::GerberArtworkFileDescriptor ());
         ex.read_word_or_quoted (artwork_files.back ().filename);
         ex.test (")");
         ex.test (",");
@@ -356,7 +356,7 @@ GerberImportData::from_string (const std::string &s)
       drill_files.clear ();
       while (! ex.test (";") && ! ex.at_end ()) {
         ex.test ("(");
-        drill_files.push_back (ext::GerberDrillFileDescriptor ());
+        drill_files.push_back (lay::GerberDrillFileDescriptor ());
         ex.read (drill_files.back ().start);
         ex.test (",");
         ex.read (drill_files.back ().stop);
@@ -373,7 +373,7 @@ GerberImportData::from_string (const std::string &s)
       free_files.clear ();
       while (! ex.test (";") && ! ex.at_end ()) {
         ex.test ("(");
-        free_files.push_back (ext::GerberFreeFileDescriptor ());
+        free_files.push_back (lay::GerberFreeFileDescriptor ());
         ex.read_word_or_quoted (free_files.back ().filename);
         ex.test (",");
         while (! ex.test (")") && ! ex.at_end ()) {
@@ -1343,7 +1343,7 @@ GerberImportDialog::layout_layer_double_clicked (QTreeWidgetItem *, int)
 
 struct FilePositionCompare
 {
-  bool operator() (const std::pair<ext::GerberMetaData, std::string> &a, const std::pair<ext::GerberMetaData, std::string> &b)
+  bool operator() (const std::pair<db::GerberMetaData, std::string> &a, const std::pair<db::GerberMetaData, std::string> &b)
   {
     if ((a.first.cu_layer_number == 0) != (b.first.cu_layer_number == 0)) {
       return (a.first.cu_layer_number == 0) < (b.first.cu_layer_number == 0);
@@ -1381,11 +1381,11 @@ GerberImportDialog::enter_page ()
         filters << tl::to_qstring ("*.gbr");
         filters << tl::to_qstring ("*.GBR");
 
-        std::vector<std::pair<ext::GerberMetaData, std::string> > files;
+        std::vector<std::pair<db::GerberMetaData, std::string> > files;
 
         QStringList entries = dir.entryList (filters);
         for (QStringList::const_iterator e = entries.begin (); e != entries.end (); ++e) {
-          ext::GerberMetaData data = ext::GerberImporter::scan (tl::to_string (dir.filePath (*e)));
+          db::GerberMetaData data = db::GerberImporter::scan (tl::to_string (dir.filePath (*e)));
           files.push_back (std::make_pair (data, tl::to_string (*e)));
         }
 
@@ -1401,7 +1401,7 @@ GerberImportDialog::enter_page ()
         mp_data->layout_layers.clear ();
 
         int min_layer = 0, max_layer = 0;
-        for (std::vector<std::pair<ext::GerberMetaData, std::string> >::const_iterator f = files.begin (); f != files.end (); ++f) {
+        for (std::vector<std::pair<db::GerberMetaData, std::string> >::const_iterator f = files.begin (); f != files.end (); ++f) {
           if (f->first.cu_layer_number > 0) {
             if (min_layer == 0 || min_layer > f->first.cu_layer_number) {
               min_layer = f->first.cu_layer_number;
@@ -1429,33 +1429,33 @@ GerberImportDialog::enter_page ()
         int next_layer = max_layer * 2;
         int hole_num = 0, profile_num = 0, legend_num = 0, solder_num = 0;
 
-        for (std::vector<std::pair<ext::GerberMetaData, std::string> >::const_iterator f = files.begin (); f != files.end (); ++f) {
+        for (std::vector<std::pair<db::GerberMetaData, std::string> >::const_iterator f = files.begin (); f != files.end (); ++f) {
 
           mp_data->free_files.push_back (GerberFreeFileDescriptor ());
           mp_data->free_files.back ().filename = tl::to_string (f->second);
 
           std::vector<int> layers;
 
-          if (f->first.function == ext::GerberMetaData::Copper) {
+          if (f->first.function == db::GerberMetaData::Copper) {
             if (l2l.find (f->first.cu_layer_number) != l2l.end ()) {
               layers.push_back (l2l [f->first.cu_layer_number]);
             }
-          } else if (f->first.function == ext::GerberMetaData::PlatedHole) {
+          } else if (f->first.function == db::GerberMetaData::PlatedHole) {
             for (int l = std::min (f->first.from_cu, f->first.to_cu); l < std::max (f->first.from_cu, f->first.to_cu); ++l) {
               if (l2v.find (l) != l2v.end ()) {
                 layers.push_back (l2v [l]);
               }
             }
-          } else if (f->first.function == ext::GerberMetaData::NonPlatedHole || f->first.function == ext::GerberMetaData::NonPlatedHole) {
+          } else if (f->first.function == db::GerberMetaData::NonPlatedHole || f->first.function == db::GerberMetaData::NonPlatedHole) {
             layers.push_back (int (mp_data->layout_layers.size ()));
             mp_data->layout_layers.push_back (db::LayerProperties (++next_layer, 0, "Hole" + tl::to_string (++hole_num)));
-          } else if (f->first.function == ext::GerberMetaData::Profile) {
+          } else if (f->first.function == db::GerberMetaData::Profile) {
             layers.push_back (int (mp_data->layout_layers.size ()));
             mp_data->layout_layers.push_back (db::LayerProperties (++next_layer, 0, "Profile" + tl::to_string (++profile_num)));
-          } else if (f->first.function == ext::GerberMetaData::Legend) {
+          } else if (f->first.function == db::GerberMetaData::Legend) {
             layers.push_back (int (mp_data->layout_layers.size ()));
             mp_data->layout_layers.push_back (db::LayerProperties (++next_layer, 0, "Legend" + tl::to_string (++legend_num)));
-          } else if (f->first.function == ext::GerberMetaData::SolderMask) {
+          } else if (f->first.function == db::GerberMetaData::SolderMask) {
             layers.push_back (int (mp_data->layout_layers.size ()));
             mp_data->layout_layers.push_back (db::LayerProperties (++next_layer, 0, "SolderMask" + tl::to_string (++solder_num)));
           }
diff --git a/src/plugins/streamers/pcb/lay_plugin/extGerberImportDialog.h b/src/plugins/streamers/pcb/lay_plugin/layGerberImportDialog.h
similarity index 96%
rename from src/plugins/streamers/pcb/lay_plugin/extGerberImportDialog.h
rename to src/plugins/streamers/pcb/lay_plugin/layGerberImportDialog.h
index 6b7f8d59f..b2a3b1e7c 100644
--- a/src/plugins/streamers/pcb/lay_plugin/extGerberImportDialog.h
+++ b/src/plugins/streamers/pcb/lay_plugin/layGerberImportDialog.h
@@ -21,8 +21,8 @@
 */
 
 
-#ifndef HDR_extGerberImportDialog
-#define HDR_extGerberImportDialog
+#ifndef HDR_dbGerberImportDialog
+#define HDR_dbGerberImportDialog
 
 #include <QDialog>
 #include <QAction>
@@ -52,10 +52,13 @@ namespace tl
   class InputStream;
 }
 
-namespace ext
+namespace db
 {
+  class GerberImporter;
+}
 
-class GerberImporter;
+namespace lay
+{
 
 struct GerberArtworkFileDescriptor
 {
@@ -107,7 +110,7 @@ public:
   std::string topcell_name;
 
   std::string get_layer_properties_file () const;
-  void setup_importer (GerberImporter *importer);
+  void setup_importer (db::GerberImporter *importer);
   void reset ();
   void load (tl::InputStream &stream);
   void load (const std::string &file);
diff --git a/src/plugins/streamers/pcb/lay_plugin/lay_plugin.pro b/src/plugins/streamers/pcb/lay_plugin/lay_plugin.pro
index ef87f8efd..7109fbd89 100644
--- a/src/plugins/streamers/pcb/lay_plugin/lay_plugin.pro
+++ b/src/plugins/streamers/pcb/lay_plugin/lay_plugin.pro
@@ -13,11 +13,11 @@ LIBS += -L$$DESTDIR/../db_plugins -lpcb
 }
 
 HEADERS = \
-  extGerberImportDialog.h \
+    layGerberImportDialog.h
 
 SOURCES = \
-  extGerberImport.cc \
-  extGerberImportDialog.cc \
+    layGerberImport.cc \
+    layGerberImportDialog.cc
 
 FORMS = \
   GerberImportDialog.ui \
diff --git a/src/plugins/streamers/pcb/unit_tests/extGerberImport.cc b/src/plugins/streamers/pcb/unit_tests/dbGerberImport.cc
similarity index 82%
rename from src/plugins/streamers/pcb/unit_tests/extGerberImport.cc
rename to src/plugins/streamers/pcb/unit_tests/dbGerberImport.cc
index fc29adac6..7319bba0b 100644
--- a/src/plugins/streamers/pcb/unit_tests/extGerberImport.cc
+++ b/src/plugins/streamers/pcb/unit_tests/dbGerberImport.cc
@@ -26,7 +26,7 @@
 #include "dbLoadLayoutOptions.h"
 #include "dbReader.h"
 #include "dbTestSupport.h"
-#include "extGerberImporter.h"
+#include "dbGerberImporter.h"
 
 #include "tlUnitTest.h"
 
@@ -53,102 +53,102 @@ static void run_test (tl::TestBase *_this, const char *dir)
 
 TEST(0_Metadata)
 {
-  ext::GerberMetaData data;
+  db::GerberMetaData data;
 
   std::string fn;
 
   fn = tl::testsrc_private ();
   fn += "/testdata/pcb/metadata/1.gbr";
-  data = ext::GerberImporter::scan (fn);
+  data = db::GerberImporter::scan (fn);
 
   EXPECT_EQ (data.creation_date, "2017-09-07T21:37;00+01:00");
   EXPECT_EQ (data.generation_software, "KLayout,0.25");
-  EXPECT_EQ (data.function, ext::GerberMetaData::Copper);
-  EXPECT_EQ (data.position, ext::GerberMetaData::Top);
+  EXPECT_EQ (data.function, db::GerberMetaData::Copper);
+  EXPECT_EQ (data.position, db::GerberMetaData::Top);
   EXPECT_EQ (data.from_cu, 0);
   EXPECT_EQ (data.to_cu, 0);
   EXPECT_EQ (data.cu_layer_number, 1);
 
   fn = tl::testsrc_private ();
   fn += "/testdata/pcb/metadata/2.gbr";
-  data = ext::GerberImporter::scan (fn);
+  data = db::GerberImporter::scan (fn);
 
   EXPECT_EQ (data.creation_date, "2017-09-07T21:37;00+01:00");
   EXPECT_EQ (data.generation_software, "KLayout,0.25");
-  EXPECT_EQ (data.function, ext::GerberMetaData::Copper);
-  EXPECT_EQ (data.position, ext::GerberMetaData::Bottom);
+  EXPECT_EQ (data.function, db::GerberMetaData::Copper);
+  EXPECT_EQ (data.position, db::GerberMetaData::Bottom);
   EXPECT_EQ (data.from_cu, 0);
   EXPECT_EQ (data.to_cu, 0);
   EXPECT_EQ (data.cu_layer_number, 4);
 
   fn = tl::testsrc_private ();
   fn += "/testdata/pcb/metadata/3.gbr";
-  data = ext::GerberImporter::scan (fn);
+  data = db::GerberImporter::scan (fn);
 
   EXPECT_EQ (data.creation_date, "2017-09-07T21:37;00+01:00");
   EXPECT_EQ (data.generation_software, "KLayout,0.25");
-  EXPECT_EQ (data.function, ext::GerberMetaData::Copper);
-  EXPECT_EQ (data.position, ext::GerberMetaData::Inner);
+  EXPECT_EQ (data.function, db::GerberMetaData::Copper);
+  EXPECT_EQ (data.position, db::GerberMetaData::Inner);
   EXPECT_EQ (data.from_cu, 0);
   EXPECT_EQ (data.to_cu, 0);
   EXPECT_EQ (data.cu_layer_number, 2);
 
   fn = tl::testsrc_private ();
   fn += "/testdata/pcb/metadata/10.gbr";
-  data = ext::GerberImporter::scan (fn);
+  data = db::GerberImporter::scan (fn);
 
   EXPECT_EQ (data.creation_date, "2017-09-07T21:37;00+01:00");
   EXPECT_EQ (data.generation_software, "KLayout,0.25");
-  EXPECT_EQ (data.function, ext::GerberMetaData::Legend);
-  EXPECT_EQ (data.position, ext::GerberMetaData::Top);
+  EXPECT_EQ (data.function, db::GerberMetaData::Legend);
+  EXPECT_EQ (data.position, db::GerberMetaData::Top);
   EXPECT_EQ (data.from_cu, 0);
   EXPECT_EQ (data.to_cu, 0);
   EXPECT_EQ (data.cu_layer_number, 0);
 
   fn = tl::testsrc_private ();
   fn += "/testdata/pcb/metadata/11.gbr";
-  data = ext::GerberImporter::scan (fn);
+  data = db::GerberImporter::scan (fn);
 
   EXPECT_EQ (data.creation_date, "2017-09-07T21:37;00+01:00");
   EXPECT_EQ (data.generation_software, "KLayout,0.25");
-  EXPECT_EQ (data.function, ext::GerberMetaData::SolderMask);
-  EXPECT_EQ (data.position, ext::GerberMetaData::Top);
+  EXPECT_EQ (data.function, db::GerberMetaData::SolderMask);
+  EXPECT_EQ (data.position, db::GerberMetaData::Top);
   EXPECT_EQ (data.from_cu, 0);
   EXPECT_EQ (data.to_cu, 0);
   EXPECT_EQ (data.cu_layer_number, 0);
 
   fn = tl::testsrc_private ();
   fn += "/testdata/pcb/metadata/12.gbr";
-  data = ext::GerberImporter::scan (fn);
+  data = db::GerberImporter::scan (fn);
 
   EXPECT_EQ (data.creation_date, "2017-09-07T21:37;00+01:00");
   EXPECT_EQ (data.generation_software, "KLayout,0.25");
-  EXPECT_EQ (data.function, ext::GerberMetaData::PlatedHole);
-  EXPECT_EQ (data.position, ext::GerberMetaData::NoPosition);
+  EXPECT_EQ (data.function, db::GerberMetaData::PlatedHole);
+  EXPECT_EQ (data.position, db::GerberMetaData::NoPosition);
   EXPECT_EQ (data.from_cu, 1);
   EXPECT_EQ (data.to_cu, 4);
   EXPECT_EQ (data.cu_layer_number, 0);
 
   fn = tl::testsrc_private ();
   fn += "/testdata/pcb/metadata/13.gbr";
-  data = ext::GerberImporter::scan (fn);
+  data = db::GerberImporter::scan (fn);
 
   EXPECT_EQ (data.creation_date, "2017-09-07T21:37;00+01:00");
   EXPECT_EQ (data.generation_software, "KLayout,0.25");
-  EXPECT_EQ (data.function, ext::GerberMetaData::NonPlatedHole);
-  EXPECT_EQ (data.position, ext::GerberMetaData::NoPosition);
+  EXPECT_EQ (data.function, db::GerberMetaData::NonPlatedHole);
+  EXPECT_EQ (data.position, db::GerberMetaData::NoPosition);
   EXPECT_EQ (data.from_cu, 1);
   EXPECT_EQ (data.to_cu, 4);
   EXPECT_EQ (data.cu_layer_number, 0);
 
   fn = tl::testsrc_private ();
   fn += "/testdata/pcb/metadata/20.drl";
-  data = ext::GerberImporter::scan (fn);
+  data = db::GerberImporter::scan (fn);
 
   EXPECT_EQ (data.creation_date, "");
   EXPECT_EQ (data.generation_software, "");
-  EXPECT_EQ (data.function, ext::GerberMetaData::Hole);
-  EXPECT_EQ (data.position, ext::GerberMetaData::NoPosition);
+  EXPECT_EQ (data.function, db::GerberMetaData::Hole);
+  EXPECT_EQ (data.position, db::GerberMetaData::NoPosition);
   EXPECT_EQ (data.from_cu, 0);
   EXPECT_EQ (data.to_cu, 0);
   EXPECT_EQ (data.cu_layer_number, 0);
diff --git a/src/plugins/streamers/pcb/unit_tests/unit_tests.pro b/src/plugins/streamers/pcb/unit_tests/unit_tests.pro
index 5c901fcd5..ad60672e6 100644
--- a/src/plugins/streamers/pcb/unit_tests/unit_tests.pro
+++ b/src/plugins/streamers/pcb/unit_tests/unit_tests.pro
@@ -6,7 +6,7 @@ TARGET = pcb_tests
 include($$PWD/../../../../lib_ut.pri)
 
 SOURCES = \
-  extGerberImport.cc \
+    dbGerberImport.cc
 
 INCLUDEPATH += $$LAY_INC $$TL_INC $$DB_INC $$GSI_INC $$PWD/../db_plugin
 DEPENDPATH += $$LAY_INC $$TL_INC $$DB_INC $$GSI_INC $$PWD/../db_plugin