diff --git a/configure.ac b/configure.ac
index a9d9c00c..2988af28 100644
--- a/configure.ac
+++ b/configure.ac
@@ -542,8 +542,8 @@ case $ac_cv_enable_mapnik in
     # C++
     AC_LANG_PUSH([C++])
     AC_PROG_CXX
-    # Mapnik3 requires C++11. Viking will use C++11 as well.
-    CXXFLAGS="$CXXFLAGS -std=c++11"
+    # Mapnik4 requires C++17. Viking will use C++17 as well.
+    CXXFLAGS="$CXXFLAGS -std=c++17"
     # Too difficult to get check working under Windows (extra dependencies needed probably Boost)- so just skip it
     if test "x$ac_cv_enable_windows" = "xno"; then
       AC_CHECK_HEADER([mapnik/map.hpp],[],[AC_MSG_ERROR([mapnik/map.hpp is needed but not found - you will need to install package 'libmapnik-dev' or similar. The feature can be disabled with --disable-mapnik])])
diff --git a/src/mapnik_interface.cpp b/src/mapnik_interface.cpp
index 45f8c900..25da9da5 100644
--- a/src/mapnik_interface.cpp
+++ b/src/mapnik_interface.cpp
@@ -46,19 +46,20 @@
 #include "globals.h"
 #include "settings.h"
 
-#if MAPNIK_VERSION < 200000
-#include <mapnik/envelope.hpp>
-#define image_32 Image32
-#define image_data_32 ImageData32
-#define box2d Envelope
-#define zoom_to_box zoomToBox
-#else
+#if MAPNIK_VERSION < 400000
 #include <mapnik/box2d.hpp>
+#endif
 #if MAPNIK_VERSION >= 300000
 // In Mapnik3 'image_32' has changed names once again
 #define image_32 image_rgba8
 #define raw_data data
 #endif
+#if MAPNIK_VERSION < 200000
+#include <mapnik/envelope.hpp>
+#define image_32 Image32
+#define image_data_32 ImageData32
+#define box2d Envelope
+#define zoom_to_box zoomToBox
 #endif
 
 #define MAPNIK_INTERFACE_TYPE            (mapnik_interface_get_type ())
@@ -93,7 +94,11 @@ struct _MapnikInterface {
 G_DEFINE_TYPE (MapnikInterface, mapnik_interface, G_TYPE_OBJECT)
 
 // Can't change prj after init - but ATM only support drawing in Spherical Mercator
+#if MAPNIK_VERSION < 400000
 static mapnik::projection prj( mapnik::MAPNIK_GMERC_PROJ );
+#else
+static mapnik::projection prj( mapnik::MAPNIK_WEBMERCATOR_PROJ );
+#endif
 
 MapnikInterface* mapnik_interface_new ()
 {
@@ -184,8 +189,12 @@ gchar* mapnik_interface_load_map_file ( MapnikInterface* mi,
 		mapnik::load_map(*mi->myMap, filename);
 
 		mi->myMap->resize(width,height);
-		mi->myMap->set_srs ( mapnik::MAPNIK_GMERC_PROJ ); // ONLY WEB MERCATOR output supported ATM
-
+		// ONLY WEB MERCATOR output supported ATM
+#if MAPNIK_VERSION < 400000
+		mi->myMap->set_srs ( mapnik::MAPNIK_GMERC_PROJ );
+#else
+		mi->myMap->set_srs ( mapnik::MAPNIK_WEBMERCATOR_PROJ );
+#endif
 		// IIRC This size is the number of pixels outside the tile to be considered so stuff is shown (i.e. particularly labels)
 		// Only set buffer size if the buffer size isn't explicitly set in the mapnik stylesheet.
 		// Alternatively render a bigger 'virtual' tile and then only use the appropriate subset