diff --git a/lib/Slic3r/ExtrusionLoop.pm b/lib/Slic3r/ExtrusionLoop.pm
index 710beaa41..2c9cffa19 100644
--- a/lib/Slic3r/ExtrusionLoop.pm
+++ b/lib/Slic3r/ExtrusionLoop.pm
@@ -2,4 +2,11 @@ package Slic3r::ExtrusionLoop;
 use strict;
 use warnings;
 
+use parent qw(Exporter);
+
+our @EXPORT_OK = qw(EXTRL_ROLE_DEFAULT EXTRL_ROLE_EXTERNAL_PERIMETER
+    EXTRL_ROLE_CONTOUR_INTERNAL_PERIMETER);
+our %EXPORT_TAGS = (roles => \@EXPORT_OK);
+
+
 1;
diff --git a/lib/Slic3r/ExtrusionPath.pm b/lib/Slic3r/ExtrusionPath.pm
index a03ff487e..20c7930ed 100644
--- a/lib/Slic3r/ExtrusionPath.pm
+++ b/lib/Slic3r/ExtrusionPath.pm
@@ -4,10 +4,9 @@ use warnings;
 
 use parent qw(Exporter);
 
-our @EXPORT_OK = qw(EXTR_ROLE_PERIMETER EXTR_ROLE_EXTERNAL_PERIMETER 
-    EXTR_ROLE_CONTOUR_INTERNAL_PERIMETER EXTR_ROLE_OVERHANG_PERIMETER
+our @EXPORT_OK = qw(EXTR_ROLE_PERIMETER EXTR_ROLE_EXTERNAL_PERIMETER EXTR_ROLE_OVERHANG_PERIMETER
     EXTR_ROLE_FILL EXTR_ROLE_SOLIDFILL EXTR_ROLE_TOPSOLIDFILL EXTR_ROLE_BRIDGE 
-    EXTR_ROLE_INTERNALBRIDGE EXTR_ROLE_SKIRT EXTR_ROLE_SUPPORTMATERIAL EXTR_ROLE_GAPFILL);
+    EXTR_ROLE_SKIRT EXTR_ROLE_SUPPORTMATERIAL EXTR_ROLE_GAPFILL);
 our %EXPORT_TAGS = (roles => \@EXPORT_OK);
 
 1;
diff --git a/lib/Slic3r/Fill.pm b/lib/Slic3r/Fill.pm
index 678e71f9a..6d1fae502 100644
--- a/lib/Slic3r/Fill.pm
+++ b/lib/Slic3r/Fill.pm
@@ -230,9 +230,7 @@ sub make_fill {
         $collection->append(
             map Slic3r::ExtrusionPath->new(
                 polyline => $_,
-                role => ($surface->surface_type == S_TYPE_INTERNALBRIDGE
-                    ? EXTR_ROLE_INTERNALBRIDGE
-                    : $is_bridge
+                role => ($is_bridge
                         ? EXTR_ROLE_BRIDGE
                         : $is_solid
                             ? (($surface->surface_type == S_TYPE_TOP) ? EXTR_ROLE_TOPSOLIDFILL : EXTR_ROLE_SOLIDFILL)
diff --git a/lib/Slic3r/GCode.pm b/lib/Slic3r/GCode.pm
index 907a0048a..6e9ed68b0 100644
--- a/lib/Slic3r/GCode.pm
+++ b/lib/Slic3r/GCode.pm
@@ -2,6 +2,7 @@ package Slic3r::GCode;
 use Moo;
 
 use List::Util qw(min max first);
+use Slic3r::ExtrusionLoop ':roles';
 use Slic3r::ExtrusionPath ':roles';
 use Slic3r::Flow ':roles';
 use Slic3r::Geometry qw(epsilon scale unscale scaled_epsilon points_coincide PI X Y B);
@@ -76,12 +77,10 @@ my %role_speeds = (
     &EXTR_ROLE_PERIMETER                    => 'perimeter',
     &EXTR_ROLE_EXTERNAL_PERIMETER           => 'external_perimeter',
     &EXTR_ROLE_OVERHANG_PERIMETER           => 'bridge',
-    &EXTR_ROLE_CONTOUR_INTERNAL_PERIMETER   => 'perimeter',
     &EXTR_ROLE_FILL                         => 'infill',
     &EXTR_ROLE_SOLIDFILL                    => 'solid_infill',
     &EXTR_ROLE_TOPSOLIDFILL                 => 'top_solid_infill',
     &EXTR_ROLE_BRIDGE                       => 'bridge',
-    &EXTR_ROLE_INTERNALBRIDGE               => 'bridge',
     &EXTR_ROLE_SKIRT                        => 'perimeter',
     &EXTR_ROLE_GAPFILL                      => 'gap_fill',
 );
@@ -217,7 +216,7 @@ sub extrude_loop {
     # find the point of the loop that is closest to the current extruder position
     # or randomize if requested
     my $last_pos = $self->last_pos;
-    if ($self->print_config->randomize_start && $loop->role == EXTR_ROLE_CONTOUR_INTERNAL_PERIMETER) {
+    if ($self->print_config->randomize_start && $loop->role == EXTRL_ROLE_CONTOUR_INTERNAL_PERIMETER) {
         $last_pos = Slic3r::Point->new(scale $self->print_config->print_center->[X], scale $self->print_config->bed_size->[Y]);
         $last_pos->rotate(rand(2*PI), $self->print_config->print_center);
     }
diff --git a/lib/Slic3r/Layer/Region.pm b/lib/Slic3r/Layer/Region.pm
index 184f7bab6..8f77ec2d0 100644
--- a/lib/Slic3r/Layer/Region.pm
+++ b/lib/Slic3r/Layer/Region.pm
@@ -2,6 +2,7 @@ package Slic3r::Layer::Region;
 use Moo;
 
 use List::Util qw(sum first);
+use Slic3r::ExtrusionLoop ':roles';
 use Slic3r::ExtrusionPath ':roles';
 use Slic3r::Flow ':roles';
 use Slic3r::Geometry qw(PI A B scale unscale chained_path points_coincide);
@@ -257,13 +258,15 @@ sub make_perimeters {
         foreach my $polynode (@$polynodes) {
             my $polygon = ($polynode->{outer} // $polynode->{hole})->clone;
             
-            my $role = EXTR_ROLE_PERIMETER;
+            my $role        = EXTR_ROLE_PERIMETER;
+            my $loop_role   = EXTRL_ROLE_DEFAULT;
             if ($is_contour ? $depth == 0 : !@{ $polynode->{children} }) {
                 # external perimeters are root level in case of contours
                 # and items with no children in case of holes
-                $role = EXTR_ROLE_EXTERNAL_PERIMETER;
+                $role       = EXTR_ROLE_EXTERNAL_PERIMETER;
+                $loop_role  = EXTRL_ROLE_EXTERNAL_PERIMETER;
             } elsif ($depth == 1 && $is_contour) {
-                $role = EXTR_ROLE_CONTOUR_INTERNAL_PERIMETER;
+                $loop_role  = EXTRL_ROLE_CONTOUR_INTERNAL_PERIMETER;
             }
             
             # detect overhanging/bridging perimeters
@@ -309,6 +312,7 @@ sub make_perimeters {
                 );
             }
             my $loop = Slic3r::ExtrusionLoop->new_from_paths(@paths);
+            $loop->role($loop_role);
             
             # return ccw contours and cw holes
             # GCode.pm will convert all of them to ccw, but it needs to know
diff --git a/t/perimeters.t b/t/perimeters.t
index b12b8f938..58ebc3ed1 100644
--- a/t/perimeters.t
+++ b/t/perimeters.t
@@ -1,4 +1,4 @@
-use Test::More tests => 9;
+use Test::More tests => 10;
 use strict;
 use warnings;
 
@@ -265,4 +265,11 @@ use Slic3r::Test;
         'overhangs printed with bridge speed';
 }
 
+{
+    my $config = Slic3r::Config->new_from_defaults;
+    $config->set('randomize_start', 1);
+    my $print = Slic3r::Test::init_print('20mm_cube', config => $config);
+    ok Slic3r::Test::gcode($print), 'successful generation of G-code with randomize_start option';
+}
+
 __END__
diff --git a/xs/src/ExtrusionEntity.cpp b/xs/src/ExtrusionEntity.cpp
index 5b15ee02e..0abab7510 100644
--- a/xs/src/ExtrusionEntity.cpp
+++ b/xs/src/ExtrusionEntity.cpp
@@ -72,23 +72,21 @@ ExtrusionPath::is_perimeter() const
 {
     return this->role == erPerimeter
         || this->role == erExternalPerimeter
-        || this->role == erOverhangPerimeter
-        || this->role == erContourInternalPerimeter;
+        || this->role == erOverhangPerimeter;
 }
 
 bool
 ExtrusionPath::is_fill() const
 {
-    return this->role == erFill
-        || this->role == erSolidFill
-        || this->role == erTopSolidFill;
+    return this->role == erInternalInfill
+        || this->role == erSolidInfill
+        || this->role == erTopSolidInfill;
 }
 
 bool
 ExtrusionPath::is_bridge() const
 {
-    return this->role == erBridge
-        || this->role == erInternalBridge
+    return this->role == erBridgeInfill
         || this->role == erOverhangPerimeter;
 }
 
diff --git a/xs/src/ExtrusionEntity.hpp b/xs/src/ExtrusionEntity.hpp
index 8504aa0ed..40e939d0e 100644
--- a/xs/src/ExtrusionEntity.hpp
+++ b/xs/src/ExtrusionEntity.hpp
@@ -11,19 +11,25 @@ class ExPolygonCollection;
 class ExtrusionEntityCollection;
 class Extruder;
 
+/* Each ExtrusionRole value identifies a distinct set of { extruder, speed } */
 enum ExtrusionRole {
     erPerimeter,
     erExternalPerimeter,
     erOverhangPerimeter,
-    erContourInternalPerimeter,
-    erFill,
-    erSolidFill,
-    erTopSolidFill,
-    erBridge,
-    erInternalBridge,
+    erInternalInfill,
+    erSolidInfill,
+    erTopSolidInfill,
+    erBridgeInfill,
+    erGapFill,
     erSkirt,
     erSupportMaterial,
-    erGapFill,
+};
+
+/* Special flags describing loop */
+enum ExtrusionLoopRole {
+    elrDefault,
+    elrExternalPerimeter,
+    elrContourInternalPerimeter,
 };
 
 class ExtrusionEntity
@@ -47,7 +53,7 @@ class ExtrusionPath : public ExtrusionEntity
     float width;
     float height;
     
-    ExtrusionPath() : mm3_per_mm(-1), width(-1), height(-1) {};
+    ExtrusionPath(ExtrusionRole role) : role(role), mm3_per_mm(-1), width(-1), height(-1) {};
     ExtrusionPath* clone() const;
     void reverse();
     Point first_point() const;
@@ -74,7 +80,9 @@ class ExtrusionLoop : public ExtrusionEntity
 {
     public:
     ExtrusionPaths paths;
+    ExtrusionLoopRole role;
     
+    ExtrusionLoop(ExtrusionLoopRole role = elrDefault) : role(role) {};
     operator Polygon() const;
     ExtrusionLoop* clone() const;
     bool make_clockwise();
diff --git a/xs/xsp/ExtrusionLoop.xsp b/xs/xsp/ExtrusionLoop.xsp
index 731c7ef59..3ab469bc5 100644
--- a/xs/xsp/ExtrusionLoop.xsp
+++ b/xs/xsp/ExtrusionLoop.xsp
@@ -41,5 +41,31 @@ ExtrusionLoop::arrayref()
     OUTPUT:
         RETVAL
 
+ExtrusionLoopRole
+ExtrusionLoop::role(...)
+    CODE:
+        if (items > 1) {
+            THIS->role = (ExtrusionLoopRole)SvUV(ST(1));
+        }
+        RETVAL = THIS->role;
+    OUTPUT:
+        RETVAL
+
 %}
 };
+
+%package{Slic3r::ExtrusionLoop};
+%{
+
+IV
+_constant()
+  ALIAS:
+    EXTRL_ROLE_DEFAULT                      = elrDefault
+    EXTRL_ROLE_EXTERNAL_PERIMETER           = elrExternalPerimeter
+    EXTRL_ROLE_CONTOUR_INTERNAL_PERIMETER   = erInternalInfill
+  PROTOTYPE:
+  CODE:
+    RETVAL = ix;
+  OUTPUT: RETVAL
+
+%}
diff --git a/xs/xsp/ExtrusionPath.xsp b/xs/xsp/ExtrusionPath.xsp
index 1b2782258..c465cc041 100644
--- a/xs/xsp/ExtrusionPath.xsp
+++ b/xs/xsp/ExtrusionPath.xsp
@@ -39,9 +39,8 @@ _new(CLASS, polyline_sv, role, mm3_per_mm, width, height)
     float           width;
     float           height;
     CODE:
-        RETVAL = new ExtrusionPath ();
+        RETVAL = new ExtrusionPath (role);
         RETVAL->polyline.from_SV_check(polyline_sv);
-        RETVAL->role            = role;
         RETVAL->mm3_per_mm      = mm3_per_mm;
         RETVAL->width           = width;
         RETVAL->height          = height;
@@ -135,15 +134,13 @@ _constant()
     EXTR_ROLE_PERIMETER                    = erPerimeter
     EXTR_ROLE_EXTERNAL_PERIMETER           = erExternalPerimeter
     EXTR_ROLE_OVERHANG_PERIMETER           = erOverhangPerimeter
-    EXTR_ROLE_CONTOUR_INTERNAL_PERIMETER   = erContourInternalPerimeter
-    EXTR_ROLE_FILL                         = erFill
-    EXTR_ROLE_SOLIDFILL                    = erSolidFill
-    EXTR_ROLE_TOPSOLIDFILL                 = erTopSolidFill
-    EXTR_ROLE_BRIDGE                       = erBridge
-    EXTR_ROLE_INTERNALBRIDGE               = erInternalBridge
+    EXTR_ROLE_FILL                         = erInternalInfill
+    EXTR_ROLE_SOLIDFILL                    = erSolidInfill
+    EXTR_ROLE_TOPSOLIDFILL                 = erTopSolidInfill
+    EXTR_ROLE_BRIDGE                       = erBridgeInfill
+    EXTR_ROLE_GAPFILL                      = erGapFill
     EXTR_ROLE_SKIRT                        = erSkirt
     EXTR_ROLE_SUPPORTMATERIAL              = erSupportMaterial
-    EXTR_ROLE_GAPFILL                      = erGapFill
   PROTOTYPE:
   CODE:
     RETVAL = ix;
diff --git a/xs/xsp/my.map b/xs/xsp/my.map
index b122d95d7..b0aed2e49 100644
--- a/xs/xsp/my.map
+++ b/xs/xsp/my.map
@@ -111,6 +111,7 @@ Ref<ModelInstance>         O_OBJECT_SLIC3R_T
 Clone<ModelInstance>       O_OBJECT_SLIC3R_T
 
 
+ExtrusionLoopRole     T_UV
 ExtrusionRole     T_UV
 FlowRole     T_UV
 PrintStep     T_UV
diff --git a/xs/xsp/typemap.xspt b/xs/xsp/typemap.xspt
index 945b104bf..7cf7c8458 100644
--- a/xs/xsp/typemap.xspt
+++ b/xs/xsp/typemap.xspt
@@ -112,6 +112,12 @@
     $CVar = (SurfaceType)SvUV($PerlVar);
   %};
 };
+%typemap{ExtrusionLoopRole}{parsed}{
+  %cpp_type{ExtrusionLoopRole};
+  %precall_code{%
+    $CVar = (ExtrusionLoopRole)SvUV($PerlVar);
+  %};
+};
 %typemap{ExtrusionRole}{parsed}{
   %cpp_type{ExtrusionRole};
   %precall_code{%