diff --git a/xs/src/libslic3r/Fill/FillBase.cpp b/xs/src/libslic3r/Fill/FillBase.cpp
index 8ed6408d1..2fa237e5f 100644
--- a/xs/src/libslic3r/Fill/FillBase.cpp
+++ b/xs/src/libslic3r/Fill/FillBase.cpp
@@ -38,7 +38,7 @@ Fill* Fill::new_from_type(const InfillPattern type)
 
 Fill* Fill::new_from_type(const std::string &type)
 {
-    static t_config_enum_values enum_keys_map = ConfigOptionEnum<InfillPattern>::get_enum_values();
+    const t_config_enum_values &enum_keys_map = ConfigOptionEnum<InfillPattern>::get_enum_values();
     t_config_enum_values::const_iterator it = enum_keys_map.find(type);
     return (it == enum_keys_map.end()) ? nullptr : new_from_type(InfillPattern(it->second));
 }
diff --git a/xs/src/perlglue.cpp b/xs/src/perlglue.cpp
index e7f03d1f5..19ec59dd7 100644
--- a/xs/src/perlglue.cpp
+++ b/xs/src/perlglue.cpp
@@ -61,135 +61,132 @@ REGISTER_CLASS(Preset, "GUI::Preset");
 REGISTER_CLASS(PresetCollection, "GUI::PresetCollection");
 REGISTER_CLASS(PresetBundle, "GUI::PresetBundle");
 
-SV*
-ConfigBase__as_hash(ConfigBase* THIS) {
-    HV* hv = newHV();
-    
-    t_config_option_keys opt_keys = THIS->keys();
-    for (t_config_option_keys::const_iterator it = opt_keys.begin(); it != opt_keys.end(); ++it)
-        (void)hv_store( hv, it->c_str(), it->length(), ConfigBase__get(THIS, *it), 0 );
-    
+SV* ConfigBase__as_hash(ConfigBase* THIS)
+{
+    HV* hv = newHV();    
+    for (auto &key : THIS->keys())
+        (void)hv_store(hv, key.c_str(), key.length(), ConfigBase__get(THIS, *it), 0);
     return newRV_noinc((SV*)hv);
 }
 
-SV*
-ConfigBase__get(ConfigBase* THIS, const t_config_option_key &opt_key) {
+SV* ConfigBase__get(ConfigBase* THIS, const t_config_option_key &opt_key)
+{
     ConfigOption* opt = THIS->option(opt_key);
-    if (opt == NULL) return &PL_sv_undef;
-    
-    const ConfigOptionDef* def = THIS->def()->get(opt_key);
-    return ConfigOption_to_SV(*opt, *def);
+    return (opt == nullptr) ? 
+        &PL_sv_undef :
+        ConfigOption_to_SV(*opt, *THIS->def->get(opt_key));
 }
 
-SV*
-ConfigOption_to_SV(const ConfigOption &opt, const ConfigOptionDef &def) {
-    if (def.type == coFloat) {
-        const ConfigOptionFloat* optv = dynamic_cast<const ConfigOptionFloat*>(&opt);
-        return newSVnv(optv->value);
-    } else if (def.type == coFloats) {
-        const ConfigOptionFloats* optv = dynamic_cast<const ConfigOptionFloats*>(&opt);
-        AV* av = newAV();
-        av_fill(av, optv->values.size()-1);
-        for (std::vector<double>::const_iterator it = optv->values.begin(); it != optv->values.end(); ++it)
-            av_store(av, it - optv->values.begin(), newSVnv(*it));
-        return newRV_noinc((SV*)av);
-    } else if (def.type == coPercent) {
-        const ConfigOptionPercent* optv = dynamic_cast<const ConfigOptionPercent*>(&opt);
-        return newSVnv(optv->value);
-    } else if (def.type == coPercents) {
-        const ConfigOptionPercents* optv = dynamic_cast<const ConfigOptionPercents*>(&opt);
+SV* ConfigOption_to_SV(const ConfigOption &opt, const ConfigOptionDef &def)
+{
+    switch (def.type) {
+    case coFloat:
+    case coPercent:
+        return newSVnv(static_cast<const ConfigOptionFloat*>(&opt)->value);
+    case coFloats:
+    case coPercents:
+    {
+        auto optv = static_cast<const ConfigOptionFloats*>(&opt);
         AV* av = newAV();
         av_fill(av, optv->values.size()-1);
         for (const double &v : optv->values)
-            av_store(av, &v - &optv->values.front(), newSVnv(v));
+            av_store(av, &v - optv->values.data(), newSVnv(v));
         return newRV_noinc((SV*)av);
-    } else if (def.type == coInt) {
-        const ConfigOptionInt* optv = dynamic_cast<const ConfigOptionInt*>(&opt);
-        return newSViv(optv->value);
-    } else if (def.type == coInts) {
-        const ConfigOptionInts* optv = dynamic_cast<const ConfigOptionInts*>(&opt);
+    }
+    case coInt:
+        return newSViv(static_cast<const ConfigOptionInt*>(&opt)->value);
+    case coInts:
+    {
+        auto optv = static_cast<const ConfigOptionInts*>(&opt);
         AV* av = newAV();
         av_fill(av, optv->values.size()-1);
-        for (std::vector<int>::const_iterator it = optv->values.begin(); it != optv->values.end(); ++it)
-            av_store(av, it - optv->values.begin(), newSViv(*it));
+        for (const int &v : optv->values)
+            av_store(av, &v - optv->values.data(), newSViv(v));
         return newRV_noinc((SV*)av);
-    } else if (def.type == coString) {
-        const ConfigOptionString* optv = dynamic_cast<const ConfigOptionString*>(&opt);
+    }
+    case coString:
+    {
+        auto optv = static_cast<const ConfigOptionString*>(&opt);
         // we don't serialize() because that would escape newlines
         return newSVpvn_utf8(optv->value.c_str(), optv->value.length(), true);
-    } else if (def.type == coStrings) {
-        const ConfigOptionStrings* optv = dynamic_cast<const ConfigOptionStrings*>(&opt);
+    }
+    case coStrings:
+    {
+        auto optv = static_cast<const ConfigOptionStrings*>(&opt);
         AV* av = newAV();
         av_fill(av, optv->values.size()-1);
-        for (std::vector<std::string>::const_iterator it = optv->values.begin(); it != optv->values.end(); ++it)
-            av_store(av, it - optv->values.begin(), newSVpvn_utf8(it->c_str(), it->length(), true));
+        for (const std::string &v : optv->values)
+            av_store(av, &v - optv->values.data(), newSVpvn_utf8(v.c_str(), v.length(), true));
         return newRV_noinc((SV*)av);
-    } else if (def.type == coPoint) {
-        const ConfigOptionPoint* optv = dynamic_cast<const ConfigOptionPoint*>(&opt);
-        return perl_to_SV_clone_ref(optv->value);
-    } else if (def.type == coPoints) {
-        const ConfigOptionPoints* optv = dynamic_cast<const ConfigOptionPoints*>(&opt);
+    }
+    case coPoint:
+        return perl_to_SV_clone_ref(static_cast<const ConfigOptionPoint*>(&opt)->value);
+    case coPoints:
+    {
+        auto optv = static_cast<const ConfigOptionPoints*>(&opt);
         AV* av = newAV();
         av_fill(av, optv->values.size()-1);
-        for (Pointfs::const_iterator it = optv->values.begin(); it != optv->values.end(); ++it)
-            av_store(av, it - optv->values.begin(), perl_to_SV_clone_ref(*it));
+        for (const Pointf &v : optv->values)
+            av_store(av, &v - optv->values.data(), perl_to_SV_clone_ref(v));
         return newRV_noinc((SV*)av);
-    } else if (def.type == coBool) {
-        const ConfigOptionBool* optv = dynamic_cast<const ConfigOptionBool*>(&opt);
-        return newSViv(optv->value ? 1 : 0);
-    } else if (def.type == coBools) {
-        const ConfigOptionBools* optv = dynamic_cast<const ConfigOptionBools*>(&opt);
+    }
+    case coBool:
+        return newSViv(static_cast<const ConfigOptionBool*>(&opt)->value ? 1 : 0);
+    case coBools:
+    {
+        auto optv = static_cast<const ConfigOptionBools*>(&opt);
         AV* av = newAV();
         av_fill(av, optv->values.size()-1);
         for (size_t i = 0; i < optv->values.size(); ++ i)
             av_store(av, i, newSViv(optv->values[i] ? 1 : 0));
         return newRV_noinc((SV*)av);
-    } else {
+    }
+    default:
         std::string serialized = opt.serialize();
         return newSVpvn_utf8(serialized.c_str(), serialized.length(), true);
     }
 }
 
-SV*
-ConfigBase__get_at(ConfigBase* THIS, const t_config_option_key &opt_key, size_t i) {
+SV* ConfigBase__get_at(ConfigBase* THIS, const t_config_option_key &opt_key, size_t i)
+{
     ConfigOption* opt = THIS->option(opt_key);
     if (opt == NULL) return &PL_sv_undef;
     
-    const ConfigOptionDef* def = THIS->def()->get(opt_key);
-    if (def->type == coFloats || def->type == coPercents) {
-        ConfigOptionFloats* optv = dynamic_cast<ConfigOptionFloats*>(opt);
-        return newSVnv(optv->get_at(i));
-    } else if (def->type == coInts) {
-        ConfigOptionInts* optv = dynamic_cast<ConfigOptionInts*>(opt);
-        return newSViv(optv->get_at(i));
-    } else if (def->type == coStrings) {
-        ConfigOptionStrings* optv = dynamic_cast<ConfigOptionStrings*>(opt);
+    const ConfigOptionDef* def = THIS->def->get(opt_key);
+    switch (def->type) {
+    case coFloats:
+    case coPercents:
+        return newSVnv(static_cast<ConfigOptionFloats*>(opt)->get_at(i));
+    case coInts:
+        return newSViv(static_cast<ConfigOptionInts*>(opt)->get_at(i));
+    case coStrings:
+    {
         // we don't serialize() because that would escape newlines
-        std::string val = optv->get_at(i);
+        const std::string &val = static_cast<ConfigOptionStrings*>(opt)->get_at(i);
         return newSVpvn_utf8(val.c_str(), val.length(), true);
-    } else if (def->type == coPoints) {
-        ConfigOptionPoints* optv = dynamic_cast<ConfigOptionPoints*>(opt);
-        return perl_to_SV_clone_ref(optv->get_at(i));
-    } else if (def->type == coBools) {
-        ConfigOptionBools* optv = dynamic_cast<ConfigOptionBools*>(opt);
-        return newSViv(optv->get_at(i) ? 1 : 0);
-    } else {
+    }
+    case coPoints:
+        return perl_to_SV_clone_ref(static_cast<ConfigOptionPoints*>(opt)->get_at(i));
+    case coBools:
+        return newSViv(static_cast<ConfigOptionBools*>(opt)->get_at(i) ? 1 : 0);
+    default:
         return &PL_sv_undef;
     }
 }
 
-bool
-ConfigBase__set(ConfigBase* THIS, const t_config_option_key &opt_key, SV* value) {
+bool ConfigBase__set(ConfigBase* THIS, const t_config_option_key &opt_key, SV* value)
+{
     ConfigOption* opt = THIS->option(opt_key, true);
     if (opt == NULL) CONFESS("Trying to set non-existing option");
     
-    const ConfigOptionDef* def = THIS->def()->get(opt_key);
-    if (def->type == coFloat) {
-        if (!looks_like_number(value)) return false;
-        ConfigOptionFloat* optv = dynamic_cast<ConfigOptionFloat*>(opt);
-        optv->value = SvNV(value);
-    } else if (def->type == coFloats) {
-        ConfigOptionFloats* optv = dynamic_cast<ConfigOptionFloats*>(opt);
+    const ConfigOptionDef* def = THIS->def->get(opt_key);
+    case coFloat:
+        if (!looks_like_number(value))
+            return false;
+        static_cast<ConfigOptionFloat*>(opt)->value = SvNV(value);
+        break;
+    case coFloats:
+    {
         std::vector<double> values;
         AV* av = (AV*)SvRV(value);
         const size_t len = av_len(av)+1;
@@ -198,9 +195,11 @@ ConfigBase__set(ConfigBase* THIS, const t_config_option_key &opt_key, SV* value)
             if (elem == NULL || !looks_like_number(*elem)) return false;
             values.push_back(SvNV(*elem));
         }
-        optv->values = values;
-    } else if (def->type == coPercents) {
-        ConfigOptionPercents* optv = dynamic_cast<ConfigOptionPercents*>(opt);
+        static_cast<ConfigOptionFloats*>(opt)->values = std::move(values);
+        break;
+    }
+    case coPercents:
+    {
         std::vector<double> values;
         AV* av = (AV*)SvRV(value);
         const size_t len = av_len(av)+1;
@@ -209,13 +208,15 @@ ConfigBase__set(ConfigBase* THIS, const t_config_option_key &opt_key, SV* value)
             if (elem == NULL || !looks_like_number(*elem)) return false;
             values.push_back(SvNV(*elem));
         }
-        optv->values = values;
-    } else if (def->type == coInt) {
+        static_cast<ConfigOptionPercents*>(opt)->values = std::move(values);
+        break;
+    }
+    case coInt:
         if (!looks_like_number(value)) return false;
-        ConfigOptionInt* optv = dynamic_cast<ConfigOptionInt*>(opt);
-        optv->value = SvIV(value);
-    } else if (def->type == coInts) {
-        ConfigOptionInts* optv = dynamic_cast<ConfigOptionInts*>(opt);
+        static_cast<ConfigOptionInt*>(opt)->value = SvIV(value);
+        break;
+    case coInts:
+    {
         std::vector<int> values;
         AV* av = (AV*)SvRV(value);
         const size_t len = av_len(av)+1;
@@ -224,25 +225,30 @@ ConfigBase__set(ConfigBase* THIS, const t_config_option_key &opt_key, SV* value)
             if (elem == NULL || !looks_like_number(*elem)) return false;
             values.push_back(SvIV(*elem));
         }
-        optv->values = values;
-    } else if (def->type == coString) {
-        ConfigOptionString* optv = dynamic_cast<ConfigOptionString*>(opt);
-        optv->value = std::string(SvPV_nolen(value), SvCUR(value));
-    } else if (def->type == coStrings) {
-        ConfigOptionStrings* optv = dynamic_cast<ConfigOptionStrings*>(opt);
+        static_cast<ConfigOptionInts*>(opt)->values = std::move(values);
+        break;
+    }
+    case coString:
+        static_cast<ConfigOptionString*>(opt)->value = std::string(SvPV_nolen(value), SvCUR(value));
+        break;
+    case coStrings:
+    {
+        auto optv = static_cast<ConfigOptionStrings*>(opt);
         optv->values.clear();
         AV* av = (AV*)SvRV(value);
         const size_t len = av_len(av)+1;
+        optv->values.reserve(len);
         for (size_t i = 0; i < len; i++) {
             SV** elem = av_fetch(av, i, 0);
             if (elem == NULL) return false;
-            optv->values.push_back(std::string(SvPV_nolen(*elem), SvCUR(*elem)));
+            optv->values.emplace_back(std::string(SvPV_nolen(*elem), SvCUR(*elem)));
         }
-    } else if (def->type == coPoint) {
-        ConfigOptionPoint* optv = dynamic_cast<ConfigOptionPoint*>(opt);
-        return from_SV_check(value, &optv->value);
-    } else if (def->type == coPoints) {
-        ConfigOptionPoints* optv = dynamic_cast<ConfigOptionPoints*>(opt);
+        break;
+    }
+    case coPoint:
+        return from_SV_check(value, &static_cast<ConfigOptionPoint*>(opt)->value);
+    case coPoints:
+    {
         std::vector<Pointf> values;
         AV* av = (AV*)SvRV(value);
         const size_t len = av_len(av)+1;
@@ -252,60 +258,62 @@ ConfigBase__set(ConfigBase* THIS, const t_config_option_key &opt_key, SV* value)
             if (elem == NULL || !from_SV_check(*elem, &point)) return false;
             values.push_back(point);
         }
-        optv->values = values;
-    } else if (def->type == coBool) {
-        ConfigOptionBool* optv = dynamic_cast<ConfigOptionBool*>(opt);
-        optv->value = SvTRUE(value);
-    } else if (def->type == coBools) {
-        ConfigOptionBools* optv = dynamic_cast<ConfigOptionBools*>(opt);
+        static_cast<ConfigOptionPoints*>(opt)->values = std::move(values);
+        break;
+    }
+    case coBool:
+        static_cast<ConfigOptionBool*>(opt)->value = SvTRUE(value);
+        break;
+    case coBools:
+    {
+        auto optv = static_cast<ConfigOptionBools*>(opt);
         optv->values.clear();
         AV* av = (AV*)SvRV(value);
         const size_t len = av_len(av)+1;
+        optv->values.reserve(len);
         for (size_t i = 0; i < len; i++) {
             SV** elem = av_fetch(av, i, 0);
             if (elem == NULL) return false;
-            optv->values.push_back(SvTRUE(*elem));
+            optv->values.emplace_back(SvTRUE(*elem));
         }
-    } else {
-        if (!opt->deserialize( std::string(SvPV_nolen(value)) )) return false;
+        break;
+    }
+    default:
+        if (! opt->deserialize(std::string(SvPV_nolen(value))))
+            return false;
     }
     return true;
 }
 
 /* This method is implemented as a workaround for this typemap bug:
    https://rt.cpan.org/Public/Bug/Display.html?id=94110 */
-bool
-ConfigBase__set_deserialize(ConfigBase* THIS, const t_config_option_key &opt_key, SV* str) {
+bool ConfigBase__set_deserialize(ConfigBase* THIS, const t_config_option_key &opt_key, SV* str)
+{
     size_t len;
     const char * c = SvPV(str, len);
     std::string value(c, len);
-    
     return THIS->set_deserialize(opt_key, value);
 }
 
-void
-ConfigBase__set_ifndef(ConfigBase* THIS, const t_config_option_key &opt_key, SV* value, bool deserialize)
+void ConfigBase__set_ifndef(ConfigBase* THIS, const t_config_option_key &opt_key, SV* value, bool deserialize)
 {
-    if (!THIS->has(opt_key)) {
-        if (deserialize) {
-            ConfigBase__set_deserialize(THIS, opt_key, value);
-        } else {
-            ConfigBase__set(THIS, opt_key, value);
-        }
-    }
+    if (THIS->has(opt_key))
+        return;
+    if (deserialize)
+        ConfigBase__set_deserialize(THIS, opt_key, value);
+    else
+        ConfigBase__set(THIS, opt_key, value);
 }
 
-bool
-StaticConfig__set(StaticConfig* THIS, const t_config_option_key &opt_key, SV* value) {
-    const ConfigOptionDef* optdef = THIS->def()->get(opt_key);
-    if (!optdef->shortcut.empty()) {
-        for (std::vector<t_config_option_key>::const_iterator it = optdef->shortcut.begin(); it != optdef->shortcut.end(); ++it) {
-            if (!StaticConfig__set(THIS, *it, value)) return false;
-        }
-        return true;
-    }
-    
-    return ConfigBase__set(THIS, opt_key, value);
+bool StaticConfig__set(StaticConfig* THIS, const t_config_option_key &opt_key, SV* value)
+{
+    const ConfigOptionDef* optdef = THIS->def->get(opt_key);
+    if (optdef->shortcut.empty())
+        return ConfigBase__set(THIS, opt_key, value);
+    for (const t_config_option_key &key : optdef->shortcut)
+        if (! StaticConfig__set(THIS, key, value))
+            return false;
+    return true;
 }
 
 SV* to_AV(ExPolygon* expolygon)
@@ -535,31 +543,5 @@ SV* to_SV(TriangleMesh* THIS)
     return sv;
 }
 
-SV*
-polynode_children_2_perl(const ClipperLib::PolyNode& node)
-{
-    AV* av = newAV();
-    const int len = node.ChildCount();
-    if (len > 0) av_extend(av, len-1);
-    for (int i = 0; i < len; ++i) {
-        av_store(av, i, polynode2perl(*node.Childs[i]));
-    }
-    return (SV*)newRV_noinc((SV*)av);
-}
-
-SV*
-polynode2perl(const ClipperLib::PolyNode& node)
-{
-    HV* hv = newHV();
-    Slic3r::Polygon p = ClipperPath_to_Slic3rPolygon(node.Contour);
-    if (node.IsHole()) {
-        (void)hv_stores( hv, "hole", Slic3r::perl_to_SV_clone_ref(p) );
-    } else {
-        (void)hv_stores( hv, "outer", Slic3r::perl_to_SV_clone_ref(p) );
-    }
-    (void)hv_stores( hv, "children", polynode_children_2_perl(node) );
-    return (SV*)newRV_noinc((SV*)hv);
-}
-
 }
 #endif
diff --git a/xs/xsp/my.map b/xs/xsp/my.map
index db94cd15f..50073d87d 100644
--- a/xs/xsp/my.map
+++ b/xs/xsp/my.map
@@ -31,6 +31,7 @@ Clone<BoundingBoxf3>       O_OBJECT_SLIC3R_T
 
 DynamicPrintConfig*        O_OBJECT_SLIC3R
 Ref<DynamicPrintConfig>    O_OBJECT_SLIC3R_T
+Clone<DynamicPrintConfig>  O_OBJECT_SLIC3R_T
 
 StaticPrintConfig*         O_OBJECT_SLIC3R
 Ref<StaticPrintConfig>     O_OBJECT_SLIC3R_T
diff --git a/xs/xsp/typemap.xspt b/xs/xsp/typemap.xspt
index 87595415d..d9d547b2b 100644
--- a/xs/xsp/typemap.xspt
+++ b/xs/xsp/typemap.xspt
@@ -39,6 +39,7 @@
 %typemap{Clone<BoundingBoxf3>}{simple};
 %typemap{DynamicPrintConfig*};
 %typemap{Ref<DynamicPrintConfig>}{simple};
+%typemap{Clone<DynamicPrintConfig>}{simple};
 %typemap{StaticPrintConfig*};
 %typemap{Ref<StaticPrintConfig>}{simple};
 %typemap{PrintObjectConfig*};