diff --git a/src/db/db/dbLayoutToNetlistFormatDefs.cc b/src/db/db/dbLayoutToNetlistFormatDefs.cc
index 82f202af8..eabcaa83a 100644
--- a/src/db/db/dbLayoutToNetlistFormatDefs.cc
+++ b/src/db/db/dbLayoutToNetlistFormatDefs.cc
@@ -28,55 +28,56 @@ namespace db
 namespace l2n_std_format
 {
   const char *l2n_magic_string_cstr = "#%l2n-klayout";
-  template<> DB_PUBLIC const std::string keys<false>::l2n_magic_string (l2n_magic_string_cstr);
-  template<> DB_PUBLIC const std::string keys<true>::l2n_magic_string (l2n_magic_string_cstr);
 
-  template<> DB_PUBLIC const std::string keys<false>::version_key ("version");
-  template<> DB_PUBLIC const std::string keys<false>::description_key ("description");
-  template<> DB_PUBLIC const std::string keys<false>::top_key ("top");
-  template<> DB_PUBLIC const std::string keys<false>::unit_key ("unit");
-  template<> DB_PUBLIC const std::string keys<false>::layer_key ("layer");
-  template<> DB_PUBLIC const std::string keys<false>::class_key ("class");
-  template<> DB_PUBLIC const std::string keys<false>::connect_key ("connect");
-  template<> DB_PUBLIC const std::string keys<false>::global_key ("global");
-  template<> DB_PUBLIC const std::string keys<false>::circuit_key ("circuit");
-  template<> DB_PUBLIC const std::string keys<false>::net_key ("net");
-  template<> DB_PUBLIC const std::string keys<false>::name_key ("name");
-  template<> DB_PUBLIC const std::string keys<false>::device_key ("device");
-  template<> DB_PUBLIC const std::string keys<false>::polygon_key ("polygon");
-  template<> DB_PUBLIC const std::string keys<false>::rect_key ("rect");
-  template<> DB_PUBLIC const std::string keys<false>::terminal_key ("terminal");
-  template<> DB_PUBLIC const std::string keys<false>::abstract_key ("abstract");
-  template<> DB_PUBLIC const std::string keys<false>::param_key ("param");
-  template<> DB_PUBLIC const std::string keys<false>::location_key ("location");
-  template<> DB_PUBLIC const std::string keys<false>::rotation_key ("rotation");
-  template<> DB_PUBLIC const std::string keys<false>::mirror_key ("mirror");
-  template<> DB_PUBLIC const std::string keys<false>::scale_key ("scale");
-  template<> DB_PUBLIC const std::string keys<false>::pin_key ("pin");
+  DB_PUBLIC std::string LongKeys::l2n_magic_string (l2n_magic_string_cstr);
+  DB_PUBLIC std::string ShortKeys::l2n_magic_string (l2n_magic_string_cstr);
+
+  DB_PUBLIC std::string LongKeys::version_key ("version");
+  DB_PUBLIC std::string LongKeys::description_key ("description");
+  DB_PUBLIC std::string LongKeys::top_key ("top");
+  DB_PUBLIC std::string LongKeys::unit_key ("unit");
+  DB_PUBLIC std::string LongKeys::layer_key ("layer");
+  DB_PUBLIC std::string LongKeys::class_key ("class");
+  DB_PUBLIC std::string LongKeys::connect_key ("connect");
+  DB_PUBLIC std::string LongKeys::global_key ("global");
+  DB_PUBLIC std::string LongKeys::circuit_key ("circuit");
+  DB_PUBLIC std::string LongKeys::net_key ("net");
+  DB_PUBLIC std::string LongKeys::name_key ("name");
+  DB_PUBLIC std::string LongKeys::device_key ("device");
+  DB_PUBLIC std::string LongKeys::polygon_key ("polygon");
+  DB_PUBLIC std::string LongKeys::rect_key ("rect");
+  DB_PUBLIC std::string LongKeys::terminal_key ("terminal");
+  DB_PUBLIC std::string LongKeys::abstract_key ("abstract");
+  DB_PUBLIC std::string LongKeys::param_key ("param");
+  DB_PUBLIC std::string LongKeys::location_key ("location");
+  DB_PUBLIC std::string LongKeys::rotation_key ("rotation");
+  DB_PUBLIC std::string LongKeys::mirror_key ("mirror");
+  DB_PUBLIC std::string LongKeys::scale_key ("scale");
+  DB_PUBLIC std::string LongKeys::pin_key ("pin");
 
   //  A, B, C, D, E, G, I, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y
-  template<> DB_PUBLIC const std::string keys<true>::version_key ("V");
-  template<> DB_PUBLIC const std::string keys<true>::description_key ("B");
-  template<> DB_PUBLIC const std::string keys<true>::top_key ("W");
-  template<> DB_PUBLIC const std::string keys<true>::unit_key ("U");
-  template<> DB_PUBLIC const std::string keys<true>::layer_key ("L");
-  template<> DB_PUBLIC const std::string keys<true>::class_key ("K");
-  template<> DB_PUBLIC const std::string keys<true>::connect_key ("C");
-  template<> DB_PUBLIC const std::string keys<true>::global_key ("G");
-  template<> DB_PUBLIC const std::string keys<true>::circuit_key ("X");
-  template<> DB_PUBLIC const std::string keys<true>::net_key ("N");
-  template<> DB_PUBLIC const std::string keys<true>::name_key ("I");
-  template<> DB_PUBLIC const std::string keys<true>::device_key ("D");
-  template<> DB_PUBLIC const std::string keys<true>::polygon_key ("Q");
-  template<> DB_PUBLIC const std::string keys<true>::rect_key ("R");
-  template<> DB_PUBLIC const std::string keys<true>::terminal_key ("T");
-  template<> DB_PUBLIC const std::string keys<true>::abstract_key ("A");
-  template<> DB_PUBLIC const std::string keys<true>::param_key ("E");
-  template<> DB_PUBLIC const std::string keys<true>::location_key ("Y");
-  template<> DB_PUBLIC const std::string keys<true>::rotation_key ("O");
-  template<> DB_PUBLIC const std::string keys<true>::mirror_key ("M");
-  template<> DB_PUBLIC const std::string keys<true>::scale_key ("S");
-  template<> DB_PUBLIC const std::string keys<true>::pin_key ("P");
+  DB_PUBLIC std::string ShortKeys::version_key ("V");
+  DB_PUBLIC std::string ShortKeys::description_key ("B");
+  DB_PUBLIC std::string ShortKeys::top_key ("W");
+  DB_PUBLIC std::string ShortKeys::unit_key ("U");
+  DB_PUBLIC std::string ShortKeys::layer_key ("L");
+  DB_PUBLIC std::string ShortKeys::class_key ("K");
+  DB_PUBLIC std::string ShortKeys::connect_key ("C");
+  DB_PUBLIC std::string ShortKeys::global_key ("G");
+  DB_PUBLIC std::string ShortKeys::circuit_key ("X");
+  DB_PUBLIC std::string ShortKeys::net_key ("N");
+  DB_PUBLIC std::string ShortKeys::name_key ("I");
+  DB_PUBLIC std::string ShortKeys::device_key ("D");
+  DB_PUBLIC std::string ShortKeys::polygon_key ("Q");
+  DB_PUBLIC std::string ShortKeys::rect_key ("R");
+  DB_PUBLIC std::string ShortKeys::terminal_key ("T");
+  DB_PUBLIC std::string ShortKeys::abstract_key ("A");
+  DB_PUBLIC std::string ShortKeys::param_key ("E");
+  DB_PUBLIC std::string ShortKeys::location_key ("Y");
+  DB_PUBLIC std::string ShortKeys::rotation_key ("O");
+  DB_PUBLIC std::string ShortKeys::mirror_key ("M");
+  DB_PUBLIC std::string ShortKeys::scale_key ("S");
+  DB_PUBLIC std::string ShortKeys::pin_key ("P");
 }
 
 }
diff --git a/src/db/db/dbLayoutToNetlistFormatDefs.h b/src/db/db/dbLayoutToNetlistFormatDefs.h
index 19fd221c5..aa54014f1 100644
--- a/src/db/db/dbLayoutToNetlistFormatDefs.h
+++ b/src/db/db/dbLayoutToNetlistFormatDefs.h
@@ -136,38 +136,78 @@ namespace db
 
 namespace l2n_std_format
 {
-  template <bool Short>
-  struct DB_PUBLIC keys
+  struct DB_PUBLIC ShortKeys
   {
-    static const std::string l2n_magic_string;
+    static std::string l2n_magic_string;
 
-    static const std::string version_key;
-    static const std::string description_key;
-    static const std::string top_key;
-    static const std::string unit_key;
-    static const std::string layer_key;
-    static const std::string class_key;
-    static const std::string connect_key;
-    static const std::string global_key;
-    static const std::string circuit_key;
-    static const std::string net_key;
-    static const std::string name_key;
-    static const std::string device_key;
-    static const std::string subcircuit_key;
-    static const std::string polygon_key;
-    static const std::string rect_key;
-    static const std::string terminal_key;
-    static const std::string abstract_key;
-    static const std::string param_key;
-    static const std::string location_key;
-    static const std::string rotation_key;
-    static const std::string mirror_key;
-    static const std::string scale_key;
-    static const std::string pin_key;
-    static const std::string indent1;
-    static const std::string indent2;
+    static std::string version_key;
+    static std::string description_key;
+    static std::string top_key;
+    static std::string unit_key;
+    static std::string layer_key;
+    static std::string class_key;
+    static std::string connect_key;
+    static std::string global_key;
+    static std::string circuit_key;
+    static std::string net_key;
+    static std::string name_key;
+    static std::string device_key;
+    static std::string subcircuit_key;
+    static std::string polygon_key;
+    static std::string rect_key;
+    static std::string terminal_key;
+    static std::string abstract_key;
+    static std::string param_key;
+    static std::string location_key;
+    static std::string rotation_key;
+    static std::string mirror_key;
+    static std::string scale_key;
+    static std::string pin_key;
+    static std::string indent1;
+    static std::string indent2;
+  };
 
-    inline static bool is_short () { return Short; }
+  struct DB_PUBLIC LongKeys
+  {
+    static std::string l2n_magic_string;
+
+    static std::string version_key;
+    static std::string description_key;
+    static std::string top_key;
+    static std::string unit_key;
+    static std::string layer_key;
+    static std::string class_key;
+    static std::string connect_key;
+    static std::string global_key;
+    static std::string circuit_key;
+    static std::string net_key;
+    static std::string name_key;
+    static std::string device_key;
+    static std::string subcircuit_key;
+    static std::string polygon_key;
+    static std::string rect_key;
+    static std::string terminal_key;
+    static std::string abstract_key;
+    static std::string param_key;
+    static std::string location_key;
+    static std::string rotation_key;
+    static std::string mirror_key;
+    static std::string scale_key;
+    static std::string pin_key;
+    static std::string indent1;
+    static std::string indent2;
+  };
+
+  template <bool Short> struct DB_PUBLIC keys;
+
+  template <> struct DB_PUBLIC keys<true> : public ShortKeys
+  {
+    inline static bool is_short () { return true; }
+  };
+
+  template <> struct DB_PUBLIC keys<false> : public LongKeys
+  {
+    inline static bool is_short () { return false; }
   };
 }
 
diff --git a/src/db/db/dbLayoutVsSchematicFormatDefs.cc b/src/db/db/dbLayoutVsSchematicFormatDefs.cc
index b58a53100..e61162fce 100644
--- a/src/db/db/dbLayoutVsSchematicFormatDefs.cc
+++ b/src/db/db/dbLayoutVsSchematicFormatDefs.cc
@@ -28,28 +28,28 @@ namespace db
 namespace lvs_std_format
 {
   const char *lvs_magic_string_cstr = "#%lvsdb-klayout";
-  template<> DB_PUBLIC const std::string keys<false>::lvs_magic_string (lvs_magic_string_cstr);
-  template<> DB_PUBLIC const std::string keys<true>::lvs_magic_string (lvs_magic_string_cstr);
+  DB_PUBLIC std::string ShortKeys::lvs_magic_string (lvs_magic_string_cstr);
+  DB_PUBLIC std::string LongKeys::lvs_magic_string (lvs_magic_string_cstr);
 
-  template<> DB_PUBLIC const std::string keys<false>::reference_key ("reference");
-  template<> DB_PUBLIC const std::string keys<false>::layout_key ("layout");
-  template<> DB_PUBLIC const std::string keys<false>::xref_key ("xref");
+  DB_PUBLIC std::string ShortKeys::reference_key ("reference");
+  DB_PUBLIC std::string ShortKeys::layout_key ("layout");
+  DB_PUBLIC std::string ShortKeys::xref_key ("xref");
 
-  template<> DB_PUBLIC const std::string keys<false>::mismatch_key ("mismatch");
-  template<> DB_PUBLIC const std::string keys<false>::match_key ("match");
-  template<> DB_PUBLIC const std::string keys<false>::nomatch_key ("nomatch");
-  template<> DB_PUBLIC const std::string keys<false>::warning_key ("warning");
-  template<> DB_PUBLIC const std::string keys<false>::skipped_key ("skipped");
+  DB_PUBLIC std::string ShortKeys::mismatch_key ("mismatch");
+  DB_PUBLIC std::string ShortKeys::match_key ("match");
+  DB_PUBLIC std::string ShortKeys::nomatch_key ("nomatch");
+  DB_PUBLIC std::string ShortKeys::warning_key ("warning");
+  DB_PUBLIC std::string ShortKeys::skipped_key ("skipped");
 
-  template<> DB_PUBLIC const std::string keys<true>::reference_key ("H");
-  template<> DB_PUBLIC const std::string keys<true>::layout_key ("J");
-  template<> DB_PUBLIC const std::string keys<true>::xref_key ("Z");
+  DB_PUBLIC std::string LongKeys::reference_key ("H");
+  DB_PUBLIC std::string LongKeys::layout_key ("J");
+  DB_PUBLIC std::string LongKeys::xref_key ("Z");
 
-  template<> DB_PUBLIC const std::string keys<true>::mismatch_key ("0");
-  template<> DB_PUBLIC const std::string keys<true>::match_key ("1");
-  template<> DB_PUBLIC const std::string keys<true>::nomatch_key ("X");
-  template<> DB_PUBLIC const std::string keys<true>::warning_key ("W");
-  template<> DB_PUBLIC const std::string keys<true>::skipped_key ("S");
+  DB_PUBLIC std::string LongKeys::mismatch_key ("0");
+  DB_PUBLIC std::string LongKeys::match_key ("1");
+  DB_PUBLIC std::string LongKeys::nomatch_key ("X");
+  DB_PUBLIC std::string LongKeys::warning_key ("W");
+  DB_PUBLIC std::string LongKeys::skipped_key ("S");
 }
 
 }
diff --git a/src/db/db/dbLayoutVsSchematicFormatDefs.h b/src/db/db/dbLayoutVsSchematicFormatDefs.h
index d96c48015..1b69e0fe1 100644
--- a/src/db/db/dbLayoutVsSchematicFormatDefs.h
+++ b/src/db/db/dbLayoutVsSchematicFormatDefs.h
@@ -121,25 +121,48 @@ namespace db
 
 namespace lvs_std_format
 {
-  template <bool Short>
-  struct DB_PUBLIC keys
-    : public l2n_std_format::keys<Short>
+  struct DB_PUBLIC ShortKeys
   {
-    typedef l2n_std_format::keys<Short> l2n_keys;
+    static std::string lvs_magic_string;
 
-    static const std::string lvs_magic_string;
+    static std::string reference_key;
+    static std::string layout_key;
+    static std::string xref_key;
 
-    static const std::string reference_key;
-    static const std::string layout_key;
-    static const std::string xref_key;
+    static std::string mismatch_key;
+    static std::string match_key;
+    static std::string nomatch_key;
+    static std::string warning_key;
+    static std::string skipped_key;
+  };
 
-    static const std::string mismatch_key;
-    static const std::string match_key;
-    static const std::string nomatch_key;
-    static const std::string warning_key;
-    static const std::string skipped_key;
+  struct DB_PUBLIC LongKeys
+  {
+    static std::string lvs_magic_string;
 
-    inline static bool is_short () { return Short; }
+    static std::string reference_key;
+    static std::string layout_key;
+    static std::string xref_key;
+
+    static std::string mismatch_key;
+    static std::string match_key;
+    static std::string nomatch_key;
+    static std::string warning_key;
+    static std::string skipped_key;
+  };
+
+  template <bool Short> struct DB_PUBLIC keys;
+
+  template <> struct DB_PUBLIC keys<true> : public l2n_std_format::keys<true>, public ShortKeys
+  {
+    typedef l2n_std_format::keys<true> l2n_keys;
+    inline static bool is_short () { return true; }
+  };
+
+  template <> struct DB_PUBLIC keys<false> : public l2n_std_format::keys<false>, public LongKeys
+  {
+    typedef l2n_std_format::keys<false> l2n_keys;
+    inline static bool is_short () { return false; }
   };
 }