diff --git a/src/ifcgeom/IfcGeomRepresentation.cpp b/src/ifcgeom/IfcGeomRepresentation.cpp
index e1c1c4e167..3be3e3bdb8 100644
--- a/src/ifcgeom/IfcGeomRepresentation.cpp
+++ b/src/ifcgeom/IfcGeomRepresentation.cpp
@@ -145,11 +145,6 @@ IfcGeom::Representation::Serialization::Serialization(const BRep& brep)
 	: Representation(brep.settings())
 	, id_(brep.id())
 {
-#ifdef IFOPSH_WITH_OPENCASCADE
-	ConversionResultShape* shape = brep.as_compound();
-	TopoDS_Compound compound = TopoDS::Compound(((ifcopenshell::geometry::OpenCascadeShape*)shape)->shape());
-	delete shape;
-
 	for (auto it = brep.begin(); it != brep.end(); ++it) {
 		int sid = -1;
 
@@ -175,12 +170,24 @@ IfcGeom::Representation::Serialization::Serialization(const BRep& brep)
 		surface_style_ids_.push_back(sid);
 	}
 
-	std::stringstream sstream;
-	BRepTools::Write(compound,sstream);
-	brep_data_ = sstream.str();
-#else
-	throw std::runtime_error("Not available without Open Cascade");
-#endif
+	if (brep.begin() != brep.end()) {
+		if (dynamic_cast<ifcopenshell::geometry::OpenCascadeShape*>(brep.begin()->Shape())) {
+			ConversionResultShape* shape = brep.as_compound();
+			shape->Serialize(brep_data_);
+			delete shape;
+		} else {
+			for (auto it = brep.begin(); it != brep.end(); ++it) {
+				std::string part;
+				it->Shape()->Serialize(part);
+				if (brep_data_.size()) {
+					brep_data_ = brep_data_ + "\n---\n" + part;
+				} else {
+					brep_data_ = part;
+				}
+			}
+		}
+	}
+
 }
 
 IfcGeom::ConversionResultShape* IfcGeom::Representation::BRep::as_compound(bool force_meters) const {
diff --git a/src/ifcgeom/Iterator.h b/src/ifcgeom/Iterator.h
index 8190783713..83e10e1065 100644
--- a/src/ifcgeom/Iterator.h
+++ b/src/ifcgeom/Iterator.h
@@ -753,6 +753,24 @@ namespace IfcGeom {
 		{
 		}
 
+		Iterator(const std::string& geometry_library, const IteratorSettings& settings, IfcParse::IfcFile* file)
+			: settings_(settings)
+			, ifc_file(file)
+			, owns_ifc_file(false)
+			, num_threads_(1)
+			, geometry_library_(geometry_library)
+		{
+		}
+
+		Iterator(const std::string& geometry_library, const IteratorSettings& settings, IfcParse::IfcFile* file, int num_threads)
+			: settings_(settings)
+			, ifc_file(file)
+			, owns_ifc_file(false)
+			, num_threads_(num_threads)
+			, geometry_library_(geometry_library)
+		{
+		}
+
 		~Iterator() {
 			if (owns_ifc_file) {
 				delete ifc_file;
diff --git a/src/ifcgeom/kernels/cgal/CgalConversionResult.cpp b/src/ifcgeom/kernels/cgal/CgalConversionResult.cpp
index 05e9861d40..94f3164262 100644
--- a/src/ifcgeom/kernels/cgal/CgalConversionResult.cpp
+++ b/src/ifcgeom/kernels/cgal/CgalConversionResult.cpp
@@ -102,6 +102,12 @@ void ifcopenshell::geometry::CgalShape::Triangulate(const IfcGeom::IteratorSetti
 
 }
 
+void ifcopenshell::geometry::CgalShape::Serialize(std::string& r) const {
+	std::stringstream sstream;
+	sstream << shape_;
+	r = sstream.str();
+}
+
 #include <CGAL/Polygon_mesh_processing/bbox.h>
 
 double ifcopenshell::geometry::CgalShape::bounding_box(void *& b) const {
diff --git a/src/ifcgeom/kernels/cgal/CgalConversionResult.h b/src/ifcgeom/kernels/cgal/CgalConversionResult.h
index 5e9acbf4c4..72d3927a6e 100644
--- a/src/ifcgeom/kernels/cgal/CgalConversionResult.h
+++ b/src/ifcgeom/kernels/cgal/CgalConversionResult.h
@@ -96,9 +96,7 @@ namespace ifcopenshell { namespace geometry {
 
 		virtual void Triangulate(const IfcGeom::IteratorSettings& settings, const ifcopenshell::geometry::taxonomy::matrix4& place, IfcGeom::Representation::Triangulation* t, int surface_style_id) const;
 		
-		virtual void Serialize(std::string&) const {
-			throw std::runtime_error("Not implemented");
-		}
+		virtual void Serialize(std::string&) const;
 
 		virtual IfcGeom::ConversionResultShape* clone() const {
 			return new CgalShape(shape_);
diff --git a/src/ifcgeom/kernels/opencascade/OpenCascadeConversionResult.cpp b/src/ifcgeom/kernels/opencascade/OpenCascadeConversionResult.cpp
index 789de9d4ae..f2a66d5838 100644
--- a/src/ifcgeom/kernels/opencascade/OpenCascadeConversionResult.cpp
+++ b/src/ifcgeom/kernels/opencascade/OpenCascadeConversionResult.cpp
@@ -217,6 +217,12 @@ void ifcopenshell::geometry::OpenCascadeShape::Triangulate(const IfcGeom::Iterat
 	BRepTools::Clean(shape_);
 }
 
+void ifcopenshell::geometry::OpenCascadeShape::Serialize(std::string& r) const {
+	std::stringstream sstream;
+	BRepTools::Write(shape_, sstream);
+	r = sstream.str();
+}
+
 int ifcopenshell::geometry::OpenCascadeShape::surface_genus() const {
 	throw std::runtime_error("Not implemented");
 }
diff --git a/src/ifcgeom/kernels/opencascade/OpenCascadeConversionResult.h b/src/ifcgeom/kernels/opencascade/OpenCascadeConversionResult.h
index c7af0ee1c1..bee6e18fa5 100644
--- a/src/ifcgeom/kernels/opencascade/OpenCascadeConversionResult.h
+++ b/src/ifcgeom/kernels/opencascade/OpenCascadeConversionResult.h
@@ -49,9 +49,7 @@ namespace ifcopenshell {
 
 			virtual void Triangulate(const IfcGeom::IteratorSettings& settings, const ifcopenshell::geometry::taxonomy::matrix4& place, IfcGeom::Representation::Triangulation* t, int surface_style_id) const;
 
-			virtual void Serialize(std::string&) const {
-				throw std::runtime_error("Not implemented");
-			}
+			virtual void Serialize(std::string&) const;
 
 			virtual IfcGeom::ConversionResultShape* clone() const {
 				return new OpenCascadeShape(shape_);
diff --git a/src/ifcopenshell-python/ifcopenshell/geom/main.py b/src/ifcopenshell-python/ifcopenshell/geom/main.py
index 8cde9af253..4fe6dfe210 100644
--- a/src/ifcopenshell-python/ifcopenshell/geom/main.py
+++ b/src/ifcopenshell-python/ifcopenshell/geom/main.py
@@ -75,7 +75,7 @@ class settings(ifcopenshell_wrapper.SerializerSettings):
 
 # Make sure people are able to use python's platform agnostic paths
 class iterator(ifcopenshell_wrapper.Iterator):
-    def __init__(self, settings, file_or_filename, num_threads=1, include=None, exclude=None):
+    def __init__(self, settings, file_or_filename, num_threads=1, include=None, exclude=None, geometry_library="opencascade"):
         self.settings = settings
         if isinstance(file_or_filename, file):
             file_or_filename = file_or_filename.wrapped_data
@@ -105,10 +105,10 @@ class iterator(ifcopenshell_wrapper.Iterator):
                 initializer = ifcopenshell_wrapper.construct_iterator_with_include_exclude
 
             self.this = initializer(
-                self.settings, file_or_filename, include_or_exclude, include is not None, num_threads
+                geometry_library, self.settings, file_or_filename, include_or_exclude, include is not None, num_threads
             )
         else:
-            ifcopenshell_wrapper.Iterator.__init__(self, settings, file_or_filename, num_threads)
+            ifcopenshell_wrapper.Iterator.__init__(self, geometry_library, settings, file_or_filename, num_threads)
 
     if has_occ: