diff --git a/CMakeLists.txt b/CMakeLists.txt
index cc923d6..a9f7545 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -21,10 +21,10 @@ endif()
 
 # set compiler flags, see http://stackoverflow.com/questions/7724569/debug-vs-release-in-cmake
 if(OPENMP_FOUND)
-	set(CMAKE_CXX_FLAGS            "-fopenmp -Ofast -fno-signed-zeros -fno-trapping-math -Wall -Wno-format-extra-args -Wextra -Wformat-nonliteral -Wformat-security -Wformat=2 -Wfatal-errors -Wextra -Wno-implicit-fallthrough -pedantic")
+	set(CMAKE_CXX_FLAGS            "-fopenmp -Ofast -fno-signed-zeros -fno-trapping-math -Wall -Wno-format-extra-args -Wextra -Wformat-nonliteral -Wformat-security -Wformat=2 -Wextra -Wno-implicit-fallthrough -pedantic")
 else()
 	message(WARNING "Configuring without OpenMP!")
-	set(CMAKE_CXX_FLAGS            "-Ofast -fno-signed-zeros -fno-trapping-math -Wall -Wno-format-extra-args -Wextra -Wformat-nonliteral -Wformat-security -Wformat=2 -Wfatal-errors -Wextra -Wno-implicit-fallthrough -pedantic")
+	set(CMAKE_CXX_FLAGS            "-Ofast -fno-signed-zeros -fno-trapping-math -Wall -Wno-format-extra-args -Wextra -Wformat-nonliteral -Wformat-security -Wformat=2 -Wextra -Wno-implicit-fallthrough -pedantic")
 endif()
 set(CMAKE_CXX_FLAGS_DEBUG          "-Og -g -DLOGLEVEL=3 -DPFAEDLE_DBG=1")
 set(CMAKE_CXX_FLAGS_MINSIZEREL     "${CMAKE_CXX_FLAGS} -DLOGLEVEL=2")
diff --git a/pfaedle.cfg b/pfaedle.cfg
index 6ad4ae9..ad04557 100644
--- a/pfaedle.cfg
+++ b/pfaedle.cfg
@@ -333,8 +333,10 @@ osm_filter_lvl4:
 	highway=living_street
 	highway=pedestrian
 	highway=service
+	psv=no
 
 osm_filter_lvl5:
+	bus=no
 	service=siding
 	access=permissive
 	access=private
diff --git a/src/pfaedle/PfaedleMain.cpp b/src/pfaedle/PfaedleMain.cpp
index 7c74e3f..abe9383 100644
--- a/src/pfaedle/PfaedleMain.cpp
+++ b/src/pfaedle/PfaedleMain.cpp
@@ -21,7 +21,7 @@
 #include "pfaedle/trgraph/Graph.h"
 #include "util/geo/output/GeoGraphJsonOutput.h"
 #include "util/geo/output/GeoJsonOutput.h"
-#include "util/json/JsonWriter.h"
+#include "util/json/Writer.h"
 #include "util/log/Log.h"
 
 using std::string;
@@ -145,10 +145,10 @@ int main(int argc, char** argv) {
 
       if (singleTrip->getShape()) {
         auto orig = Collector::getWebMercLine(singleTrip->getShape(), -1, -1);
-        o.print(orig, {{"ver", "old"}});
+        o.print(orig, util::json::Dict{{"ver", "old"}});
       }
 
-      o.print(l, {{"ver", "new"}});
+      o.print(l, util::json::Dict{{"ver", "new"}});
       o.flush();
       pstr.close();
 
diff --git a/src/pfaedle/eval/Collector.cpp b/src/pfaedle/eval/Collector.cpp
index 334641f..5e7e7b7 100644
--- a/src/pfaedle/eval/Collector.cpp
+++ b/src/pfaedle/eval/Collector.cpp
@@ -107,11 +107,11 @@ double Collector::add(const Trip* t, const Shape* oldS, const Shape* newS,
   FLine newLCut;
 
   for (auto oldL : oldSegs) {
-    gjout.print(oldL, {{"ver", "old"}});
+    gjout.print(oldL, util::json::Dict{{"ver", "old"}});
     oldLCut.insert(oldLCut.end(), oldL.begin(), oldL.end());
   }
   for (auto newL : newSegs) {
-    gjout.print(newL, {{"ver", "new"}});
+    gjout.print(newL, util::json::Dict{{"ver", "new"}});
     newLCut.insert(newLCut.end(), newL.begin(), newL.end());
   }
 
diff --git a/src/pfaedle/netgraph/EdgePL.h b/src/pfaedle/netgraph/EdgePL.h
index b568fed..3a245a4 100644
--- a/src/pfaedle/netgraph/EdgePL.h
+++ b/src/pfaedle/netgraph/EdgePL.h
@@ -5,9 +5,9 @@
 #ifndef PFAEDLE_NETGRAPH_EDGEPL_H_
 #define PFAEDLE_NETGRAPH_EDGEPL_H_
 
-#include <map>
 #include <set>
 #include <string>
+#include <vector>
 #include "ad/cppgtfs/gtfs/Feed.h"
 #include "util/String.h"
 #include "util/geo/GeoGraph.h"
@@ -33,12 +33,14 @@ class EdgePL : public GeoEdgePL<float> {
     }
   }
   const util::geo::FLine* getGeom() const { return &_l; }
-  void getAttrs(std::map<std::string, std::string>* obj) const {
-    (*obj)["num_trips"] = std::to_string(_trips.size());
-    (*obj)["route_short_names"] =
-        util::implode(_routeShortNames.begin(), _routeShortNames.end(), ", ");
-    (*obj)["trip_short_names"] =
-        util::implode(_tripShortNames.begin(), _tripShortNames.end(), ", ");
+  util::json::Dict getAttrs() const {
+    util::json::Dict obj;
+    obj["num_trips"] = static_cast<int>(_trips.size());
+    obj["route_short_names"] = util::json::Array(
+        _routeShortNames.begin(), _routeShortNames.end());
+    obj["trip_short_names"] = util::json::Array(_tripShortNames.begin(),
+                                                       _tripShortNames.end());
+    return obj;
   }
 
  private:
diff --git a/src/pfaedle/netgraph/NodePL.h b/src/pfaedle/netgraph/NodePL.h
index 8588536..944c63e 100644
--- a/src/pfaedle/netgraph/NodePL.h
+++ b/src/pfaedle/netgraph/NodePL.h
@@ -25,8 +25,8 @@ class NodePL : public GeoNodePL<float> {
   NodePL(const util::geo::FPoint& geom) { _geom = geom; }  // NOLINT
 
   const util::geo::FPoint* getGeom() const { return &_geom; }
-  void getAttrs(std::map<std::string, std::string>* attrs) const {
-    UNUSED(attrs);
+  util::json::Dict getAttrs() const {
+    return util::json::Dict();
   }
 
  private:
diff --git a/src/pfaedle/osm/OsmBuilder.cpp b/src/pfaedle/osm/OsmBuilder.cpp
index cb7839f..db39e03 100644
--- a/src/pfaedle/osm/OsmBuilder.cpp
+++ b/src/pfaedle/osm/OsmBuilder.cpp
@@ -190,7 +190,7 @@ void OsmBuilder::read(const std::string& path, const OsmReadOpts& opts,
   deleteOrphEdgs(g);
 
   LOG(VDEBUG) << "Collapsing edges...";
-  collapseEdges(g);
+  // collapseEdges(g);
 
   LOG(VDEBUG) << "Deleting orphan nodes...";
   deleteOrphNds(g);
@@ -212,8 +212,14 @@ void OsmBuilder::read(const std::string& path, const OsmReadOpts& opts,
   LOG(VDEBUG) << "Write dummy node self-edges...";
   writeSelfEdgs(g);
 
-  LOG(DEBUG) << "Graph has " << g->getNds()->size() << " nodes and " << comps
-            << " connected component(s)";
+  size_t numEdges = 0;
+
+  for (auto* n : *g->getNds()) {
+    numEdges += n->getAdjListOut().size();
+  }
+
+  LOG(DEBUG) << "Graph has " << g->getNds()->size() << " nodes, " << numEdges
+             << " edges and " << comps << " connected component(s)";
 }
 
 // _____________________________________________________________________________
@@ -367,8 +373,7 @@ void OsmBuilder::readWriteWays(xml::File* i, util::xml::XmlWriter* o,
 }
 
 // _____________________________________________________________________________
-NodePL OsmBuilder::plFromGtfs(const Stop* s,
-                              const OsmReadOpts& ops) const {
+NodePL OsmBuilder::plFromGtfs(const Stop* s, const OsmReadOpts& ops) const {
   NodePL ret(util::geo::latLngToWebMerc<float>(s->getLat(), s->getLng()),
              StatInfo(ops.statNormzer(s->getName()),
                       ops.trackNormzer(s->getPlatformCode()), false));
@@ -1671,7 +1676,6 @@ uint32_t OsmBuilder::writeComps(Graph* g) const {
     }
   }
 
-
   // the last comp was not used
   delete comp;
 
diff --git a/src/pfaedle/router/EdgePL.cpp b/src/pfaedle/router/EdgePL.cpp
index 64c8f15..9473c7c 100644
--- a/src/pfaedle/router/EdgePL.cpp
+++ b/src/pfaedle/router/EdgePL.cpp
@@ -76,24 +76,27 @@ void EdgePL::setCost(const router::EdgeCost& c) { _cost = c; }
 
 
 // _____________________________________________________________________________
-void EdgePL::getAttrs(std::map<std::string, std::string>* obj) const {
-  (*obj)["cost"] = std::to_string(_cost.getValue());
-  (*obj)["from_edge"] = util::toString(_startE);
-  (*obj)["to_edge"] = util::toString(_endE);
-  (*obj)["cost_m_lvl1"] = std::to_string(_cost.meterDistLvl1);
-  (*obj)["cost_m_lvl0"] = std::to_string(_cost.meterDist);
-  (*obj)["cost_m_lvl1"] = std::to_string(_cost.meterDistLvl1);
-  (*obj)["cost_m_lvl2"] = std::to_string(_cost.meterDistLvl2);
-  (*obj)["cost_m_lvl3"] = std::to_string(_cost.meterDistLvl3);
-  (*obj)["cost_m_lvl4"] = std::to_string(_cost.meterDistLvl4);
-  (*obj)["cost_m_lvl5"] = std::to_string(_cost.meterDistLvl5);
-  (*obj)["cost_m_lvl6"] = std::to_string(_cost.meterDistLvl6);
-  (*obj)["cost_m_lvl7"] = std::to_string(_cost.meterDistLvl7);
-  (*obj)["cost_fullturn"] = std::to_string(_cost.fullTurns);
-  (*obj)["cost_st_passthru"] = std::to_string(_cost.passThruStations);
-  (*obj)["cost_m_oneway"] = std::to_string(_cost.oneWayMeters);
-  (*obj)["cost_m_lineunmatch"] = std::to_string(_cost.lineUnmatchedMeters);
-  (*obj)["cost_reach_node_pen"] = std::to_string(_cost.reachPen);
-  (*obj)["cost_oneway_event"] = std::to_string(_cost.oneWayEdges);
-  (*obj)["dummy"] = _edges.size() ? "no" : "yes";
+util::json::Dict EdgePL::getAttrs() const {
+  util::json::Dict obj;
+  obj["cost"] = std::to_string(_cost.getValue());
+  obj["from_edge"] = util::toString(_startE);
+  obj["to_edge"] = util::toString(_endE);
+  obj["cost_m_lvl1"] = std::to_string(_cost.meterDistLvl1);
+  obj["cost_m_lvl0"] = std::to_string(_cost.meterDist);
+  obj["cost_m_lvl1"] = std::to_string(_cost.meterDistLvl1);
+  obj["cost_m_lvl2"] = std::to_string(_cost.meterDistLvl2);
+  obj["cost_m_lvl3"] = std::to_string(_cost.meterDistLvl3);
+  obj["cost_m_lvl4"] = std::to_string(_cost.meterDistLvl4);
+  obj["cost_m_lvl5"] = std::to_string(_cost.meterDistLvl5);
+  obj["cost_m_lvl6"] = std::to_string(_cost.meterDistLvl6);
+  obj["cost_m_lvl7"] = std::to_string(_cost.meterDistLvl7);
+  obj["cost_fullturn"] = std::to_string(_cost.fullTurns);
+  obj["cost_st_passthru"] = std::to_string(_cost.passThruStations);
+  obj["cost_m_oneway"] = std::to_string(_cost.oneWayMeters);
+  obj["cost_m_lineunmatch"] = std::to_string(_cost.lineUnmatchedMeters);
+  obj["cost_reach_node_pen"] = std::to_string(_cost.reachPen);
+  obj["cost_oneway_event"] = std::to_string(_cost.oneWayEdges);
+  obj["dummy"] = _edges.size() ? "no" : "yes";
+
+  return obj;
 }
diff --git a/src/pfaedle/router/EdgePL.h b/src/pfaedle/router/EdgePL.h
index 4838601..a5dee5e 100644
--- a/src/pfaedle/router/EdgePL.h
+++ b/src/pfaedle/router/EdgePL.h
@@ -19,7 +19,7 @@ class EdgePL : public GeoEdgePL<float> {
  public:
   EdgePL() : _cost(), _start(0), _end(0), _startE(0), _endE(0) {}
   const util::geo::FLine* getGeom() const;
-  void getAttrs(std::map<std::string, std::string>* attrs) const;
+  util::json::Dict getAttrs() const;
   router::EdgeList* getEdges();
   const router::EdgeList& getEdges() const;
   void setStartNode(const trgraph::Node* s);
diff --git a/src/pfaedle/router/NodePL.h b/src/pfaedle/router/NodePL.h
index 1ab743c..e8aada3 100644
--- a/src/pfaedle/router/NodePL.h
+++ b/src/pfaedle/router/NodePL.h
@@ -23,8 +23,9 @@ class NodePL : public GeoNodePL<float> {
   const util::geo::FPoint* getGeom() const {
     return !_n ? 0 : _n->pl().getGeom();
   }
-  void getAttrs(std::map<std::string, std::string>* attrs) const {
-    if (_n) _n->pl().getAttrs(attrs);
+  util::json::Dict getAttrs() const {
+    if (_n) return _n->pl().getAttrs();
+    return util::json::Dict();
   }
 
  private:
diff --git a/src/pfaedle/trgraph/EdgePL.cpp b/src/pfaedle/trgraph/EdgePL.cpp
index 9612db7..8b63d04 100644
--- a/src/pfaedle/trgraph/EdgePL.cpp
+++ b/src/pfaedle/trgraph/EdgePL.cpp
@@ -108,11 +108,12 @@ const util::geo::FLine* EdgePL::getGeom() const { return _l; }
 util::geo::FLine* EdgePL::getGeom() { return _l; }
 
 // _____________________________________________________________________________
-void EdgePL::getAttrs(std::map<std::string, std::string>* obj) const {
-  (*obj)["m_length"] = std::to_string(_length);
-  (*obj)["oneway"] = std::to_string(static_cast<int>(_oneWay));
-  (*obj)["level"] = std::to_string(_lvl);
-  (*obj)["restriction"] = isRestricted() ? "yes" : "no";
+util::json::Dict EdgePL::getAttrs() const {
+  util::json::Dict obj;
+  obj["m_length"] = std::to_string(_length);
+  obj["oneway"] = std::to_string(static_cast<int>(_oneWay));
+  obj["level"] = std::to_string(_lvl);
+  obj["restriction"] = isRestricted() ? "yes" : "no";
 
   std::stringstream ss;
   bool first = false;
@@ -127,7 +128,8 @@ void EdgePL::getAttrs(std::map<std::string, std::string>* obj) const {
     first = true;
   }
 
-  (*obj)["lines"] = ss.str();
+  obj["lines"] = ss.str();
+  return obj;
 }
 
 // _____________________________________________________________________________
diff --git a/src/pfaedle/trgraph/EdgePL.h b/src/pfaedle/trgraph/EdgePL.h
index b467f44..0eb5800 100644
--- a/src/pfaedle/trgraph/EdgePL.h
+++ b/src/pfaedle/trgraph/EdgePL.h
@@ -57,7 +57,7 @@ class EdgePL : public GeoEdgePL<float> {
   void addPoint(const util::geo::FPoint& p);
 
   // Fill obj with k/v pairs describing the parameters of this payload.
-  void getAttrs(std::map<std::string, std::string>* obj) const;
+  util::json::Dict getAttrs() const;
 
   // Return the length in meters stored for this edge payload
   double getLength() const;
diff --git a/src/pfaedle/trgraph/NodePL.cpp b/src/pfaedle/trgraph/NodePL.cpp
index c4bd10c..53a79cc 100644
--- a/src/pfaedle/trgraph/NodePL.cpp
+++ b/src/pfaedle/trgraph/NodePL.cpp
@@ -114,18 +114,19 @@ const util::geo::FPoint* NodePL::getGeom() const { return &_geom; }
 void NodePL::setGeom(const util::geo::FPoint& geom) { _geom = geom; }
 
 // _____________________________________________________________________________
-void NodePL::getAttrs(std::map<std::string, std::string>* obj) const {
-  (*obj)["component"] = std::to_string(reinterpret_cast<size_t>(_component));
+util::json::Dict NodePL::getAttrs() const {
+  util::json::Dict obj;
+  obj["component"] = std::to_string(reinterpret_cast<size_t>(_component));
 #ifdef PFAEDLE_DBG
-  (*obj)["dijkstra_vis"] = _vis ? "yes" : "no";
+  obj["dijkstra_vis"] = _vis ? "yes" : "no";
 #endif
   if (getSI()) {
-    (*obj)["station_info_ptr"] = util::toString(_si);
-    (*obj)["station_name"] = _si->getName();
-    (*obj)["station_alt_names"] = util::implode(_si->getAltNames(), ",");
-    (*obj)["from_osm"] = _si->isFromOsm() ? "yes" : "no";
-    (*obj)["station_platform"] = _si->getTrack();
-    (*obj)["station_group"] =
+    obj["station_info_ptr"] = util::toString(_si);
+    obj["station_name"] = _si->getName();
+    obj["station_alt_names"] = util::implode(_si->getAltNames(), ",");
+    obj["from_osm"] = _si->isFromOsm() ? "yes" : "no";
+    obj["station_platform"] = _si->getTrack();
+    obj["station_group"] =
         std::to_string(reinterpret_cast<size_t>(_si->getGroup()));
 
     std::stringstream gtfsIds;
@@ -135,8 +136,9 @@ void NodePL::getAttrs(std::map<std::string, std::string>* obj) const {
       }
     }
 
-    (*obj)["station_group_stops"] = gtfsIds.str();
+    obj["station_group_stops"] = gtfsIds.str();
   }
+  return obj;
 }
 
 // _____________________________________________________________________________
diff --git a/src/pfaedle/trgraph/NodePL.h b/src/pfaedle/trgraph/NodePL.h
index a9bc4a9..74b0483 100644
--- a/src/pfaedle/trgraph/NodePL.h
+++ b/src/pfaedle/trgraph/NodePL.h
@@ -37,7 +37,7 @@ class NodePL : public GeoNodePL<float> {
   void setGeom(const util::geo::FPoint& geom);
 
   // Fill obj with k/v pairs describing the parameters of this payload.
-  void getAttrs(std::map<std::string, std::string>* attrs) const;
+  util::json::Dict getAttrs() const;
 
   // Set the station info for this node
   void setSI(const StatInfo& si);
diff --git a/src/util/geo/Box.h b/src/util/geo/Box.h
index 43f05e9..9642b31 100644
--- a/src/util/geo/Box.h
+++ b/src/util/geo/Box.h
@@ -77,6 +77,8 @@ class RotatedBox {
   const Point<T>& getCenter() const { return _center; }
   Point<T>& getCenter() { return _center; }
 
+  void setDegree(double deg) { _deg = deg; }
+
  private:
   Box<T> _box;
   double _deg;
diff --git a/src/util/geo/Geo.h b/src/util/geo/Geo.h
index 94bb67a..53eabae 100644
--- a/src/util/geo/Geo.h
+++ b/src/util/geo/Geo.h
@@ -219,15 +219,15 @@ inline Box<T> minbox() {
 // _____________________________________________________________________________
 template <typename T>
 inline RotatedBox<T> shrink(const RotatedBox<T>& b, double d) {
-  double xd = b.b.getUpperRight().getX() - b.b.getLowerLeft().getX();
-  double yd = b.b.getUpperRight().getY() - b.b.getLowerLeft().getY();
+  double xd = b.getBox().getUpperRight().getX() - b.getBox().getLowerLeft().getX();
+  double yd = b.getBox().getUpperRight().getY() - b.getBox().getLowerLeft().getY();
 
   if (xd <= 2 * d) d = xd / 2 - 1;
   if (yd <= 2 * d) d = yd / 2 - 1;
 
   Box<T> r(
-      Point<T>(b.b.getLowerLeft().getX() + d, b.b.getLowerLeft().getY() + d),
-      Point<T>(b.b.getUpperRight().getX() - d, b.b.getUpperRight().getY() - d));
+      Point<T>(b.getBox().getLowerLeft().getX() + d, b.getBox().getLowerLeft().getY() + d),
+      Point<T>(b.getBox().getUpperRight().getX() - d, b.getBox().getUpperRight().getY() - d));
 
   return RotatedBox<T>(r, b.getDegree(), b.getCenter());
 }
@@ -1137,8 +1137,8 @@ inline Polygon<T> convexHull(const RotatedBox<T>& b) {
 
 // _____________________________________________________________________________
 template <typename T>
-inline size_t convexHullImpl(const Line<T>& a, size_t p1, size_t p2,
-                             Line<double>* h, uint8_t d) {
+inline size_t convexHullImpl(const MultiPoint<T>& a, size_t p1, size_t p2,
+                             Line<T>* h, uint8_t d) {
   // quickhull by Barber, Dobkin & Huhdanpaa
   Point<T> pa;
   bool found = false;
@@ -1162,7 +1162,7 @@ inline size_t convexHullImpl(const Line<T>& a, size_t p1, size_t p2,
 
 // _____________________________________________________________________________
 template <typename T>
-inline Polygon<T> convexHull(const Line<T>& l) {
+inline Polygon<T> convexHull(const MultiPoint<T>& l) {
   if (l.size() == 2) return convexHull(LineSegment<T>(l[0], l[1]));
   if (l.size() == 1) return convexHull(l[0]);
 
@@ -1185,6 +1185,14 @@ inline Polygon<T> convexHull(const Polygon<T>& p) {
   return convexHull(p.getOuter());
 }
 
+// _____________________________________________________________________________
+template <typename T>
+inline Polygon<T> convexHull(const MultiLine<T>& ls) {
+  MultiPoint<T> mp;
+  for (const auto& l : ls) mp.insert(mp.end(), l.begin(), l.end());
+  return convexHull(mp);
+}
+
 // _____________________________________________________________________________
 template <typename T>
 inline Box<T> extendBox(const Line<T>& l, Box<T> b) {
@@ -1200,6 +1208,12 @@ inline Box<T> extendBox(const LineSegment<T>& ls, Box<T> b) {
   return b;
 }
 
+// _____________________________________________________________________________
+template <typename T>
+inline Box<T> extendBox(const Polygon<T>& ls, Box<T> b) {
+  return extendBox(ls.getOuter(), b);
+}
+
 // _____________________________________________________________________________
 template <template <typename> class Geometry, typename T>
 inline Box<T> extendBox(const std::vector<Geometry<T>>& multigeom, Box<T> b) {
@@ -1263,7 +1277,7 @@ inline double commonArea(const Box<T>& ba, const Box<T>& bb) {
 
 // _____________________________________________________________________________
 template <template <typename> class Geometry, typename T>
-inline RotatedBox<T> getFullEnvelope(Geometry<T> pol) {
+inline RotatedBox<T> getFullEnvelope(std::vector<Geometry<T>> pol) {
   Point<T> center = centroid(pol);
   Box<T> tmpBox = getBoundingBox(pol);
   double rotateDeg = 0;
@@ -1287,6 +1301,14 @@ inline RotatedBox<T> getFullEnvelope(Geometry<T> pol) {
   return RotatedBox<T>(tmpBox, rotateDeg, center);
 }
 
+// _____________________________________________________________________________
+template <template <typename> class Geometry, typename T>
+inline RotatedBox<T> getFullEnvelope(const Geometry<T> pol) {
+  std::vector<Geometry<T>> mult;
+  mult.push_back(pol);
+  return getFullEnvelope(mult);
+}
+
 // _____________________________________________________________________________
 template <typename T>
 inline RotatedBox<T> getOrientedEnvelopeAvg(MultiLine<T> ml) {
@@ -1298,18 +1320,18 @@ inline RotatedBox<T> getOrientedEnvelopeAvg(MultiLine<T> ml) {
   ml = rotate(ml, -rbox.getDegree() - 45, center);
 
   double bestDeg = -45;
-  double score = parallelity(rbox.b, ml);
+  double score = parallelity(rbox.getBox(), ml);
 
   for (double i = -45; i <= 45; i += .5) {
     ml = rotate(ml, -.5, center);
-    double p = parallelity(rbox.b, ml);
-    if (parallelity(rbox.b, ml) > score) {
+    double p = parallelity(rbox.getBox(), ml);
+    if (parallelity(rbox.getBox(), ml) > score) {
       bestDeg = i;
       score = p;
     }
   }
 
-  rbox.rotateDeg += bestDeg;
+  rbox.setDegree(rbox.getDegree() + bestDeg);
 
   // move the box along 45deg angles from its origin until it fits the ml
   // = until the intersection of its hull and the box is largest
diff --git a/src/util/geo/GeoGraph.h b/src/util/geo/GeoGraph.h
index 8579366..9b68790 100644
--- a/src/util/geo/GeoGraph.h
+++ b/src/util/geo/GeoGraph.h
@@ -7,6 +7,7 @@
 
 #include <map>
 #include "util/geo/Geo.h"
+#include "util/json/Writer.h"
 
 namespace util {
 namespace geograph {
@@ -15,14 +16,14 @@ template<typename T>
 class GeoEdgePL {
  public:
   virtual const util::geo::Line<T>* getGeom() const = 0;
-  virtual void getAttrs(std::map<std::string, std::string>* m) const = 0;
+  virtual json::Dict getAttrs() const = 0;
 };
 
 template<typename T>
 class GeoNodePL {
  public:
   virtual const util::geo::Point<T>* getGeom() const = 0;
-  virtual void getAttrs(std::map<std::string, std::string>* m) const = 0;
+  virtual json::Dict getAttrs() const = 0;
 };
 
 }  // namespace geograph
diff --git a/src/util/geo/PolyLine.h b/src/util/geo/PolyLine.h
index b95f038..0cc9c03 100644
--- a/src/util/geo/PolyLine.h
+++ b/src/util/geo/PolyLine.h
@@ -7,6 +7,7 @@
 
 #include <cfloat>
 #include <ostream>
+#include <iomanip>
 #include <string>
 #include <vector>
 #include "Geo.h"
diff --git a/src/util/geo/output/GeoGraphJsonOutput.tpp b/src/util/geo/output/GeoGraphJsonOutput.tpp
index ba316a6..e026a27 100644
--- a/src/util/geo/output/GeoGraphJsonOutput.tpp
+++ b/src/util/geo/output/GeoGraphJsonOutput.tpp
@@ -2,8 +2,6 @@
 // Chair of Algorithms and Data Structures.
 // Authors: Patrick Brosi <brosi@informatik.uni-freiburg.de>
 
-using util::geo::output::Attrs;
-
 // _____________________________________________________________________________
 template <typename T>
 Line<T> GeoGraphJsonOutput::createLine(const util::geo::Point<T>& a,
@@ -24,11 +22,13 @@ void GeoGraphJsonOutput::print(const util::graph::Graph<N, E>& outG,
   for (util::graph::Node<N, E>* n : outG.getNds()) {
     if (!n->pl().getGeom()) continue;
 
-    Attrs props = {{"id", toString(n)},
+    json::Dict props{{"id", toString(n)},
                    {"deg", toString(n->getInDeg() + n->getOutDeg())},
                    {"deg_out", toString(n->getOutDeg())},
                    {"deg_in", toString(n->getInDeg())}};
-    n->pl().getAttrs(&props);
+
+    auto addProps = n->pl().getAttrs();
+    props.insert(addProps.begin(), addProps.end());
 
     _out.print(*n->pl().getGeom(), props);
   }
@@ -38,11 +38,12 @@ void GeoGraphJsonOutput::print(const util::graph::Graph<N, E>& outG,
     for (graph::Edge<N, E>* e : n->getAdjListOut()) {
       // to avoid double output for undirected graphs
       if (e->getFrom() != n) continue;
-      Attrs props{{"from", toString(e->getFrom())},
+      json::Dict props{{"from", toString(e->getFrom())},
                   {"to", toString(e->getTo())},
                   {"id", toString(e)}};
 
-      e->pl().getAttrs(&props);
+      auto addProps = e->pl().getAttrs();
+      props.insert(addProps.begin(), addProps.end());
 
       if (!e->pl().getGeom() || !e->pl().getGeom()->size()) {
         if (e->getFrom()->pl().getGeom()) {
diff --git a/src/util/geo/output/GeoJsonOutput.h b/src/util/geo/output/GeoJsonOutput.h
index d555a32..834507c 100644
--- a/src/util/geo/output/GeoJsonOutput.h
+++ b/src/util/geo/output/GeoJsonOutput.h
@@ -10,26 +10,24 @@
 #include <map>
 #include "util/String.h"
 #include "util/geo/Geo.h"
-#include "util/json/JsonWriter.h"
+#include "util/json/Writer.h"
 
 namespace util {
 namespace geo {
 namespace output {
 
-typedef std::map<std::string, std::string> Attrs;
-
 class GeoJsonOutput {
  public:
   GeoJsonOutput(std::ostream& str);
   ~GeoJsonOutput();
   template <typename T>
-  void print(const Point<T>& p, Attrs attrs);
+  void print(const Point<T>& p, json::Val attrs);
   template <typename T>
-  void print(const Line<T>& l, Attrs attrs);
+  void print(const Line<T>& l, json::Val attrs);
   void flush();
 
  private:
-  json::JsonWriter _wr;
+  json::Writer _wr;
 };
 
 #include "util/geo/output/GeoJsonOutput.tpp"
diff --git a/src/util/geo/output/GeoJsonOutput.tpp b/src/util/geo/output/GeoJsonOutput.tpp
index faec0c9..1f599cf 100644
--- a/src/util/geo/output/GeoJsonOutput.tpp
+++ b/src/util/geo/output/GeoJsonOutput.tpp
@@ -4,7 +4,7 @@
 
 // _____________________________________________________________________________
 template <typename T>
-void GeoJsonOutput::print(const Point<T>& p, Attrs attrs) {
+void GeoJsonOutput::print(const Point<T>& p, json::Val attrs) {
   _wr.obj();
   _wr.keyVal("type", "Feature");
 
@@ -18,13 +18,13 @@ void GeoJsonOutput::print(const Point<T>& p, Attrs attrs) {
   _wr.close();
   _wr.close();
   _wr.key("properties");
-  _wr.obj(attrs);
+  _wr.val(attrs);
   _wr.close();
 }
 
 // _____________________________________________________________________________
 template <typename T>
-void GeoJsonOutput::print(const Line<T>& line, Attrs attrs) {
+void GeoJsonOutput::print(const Line<T>& line, json::Val attrs) {
   if (!line.size()) return;
   _wr.obj();
   _wr.keyVal("type", "Feature");
@@ -37,12 +37,12 @@ void GeoJsonOutput::print(const Line<T>& line, Attrs attrs) {
   for (auto p : line) {
     _wr.arr();
     _wr.val(p.getX());
-    _wr.val(p.template getY());
+    _wr.val(p.getY());
     _wr.close();
   }
   _wr.close();
   _wr.close();
   _wr.key("properties");
-  _wr.obj(attrs);
+  _wr.val(attrs);
   _wr.close();
 }
diff --git a/src/util/json/JsonWriter.cpp b/src/util/json/JsonWriter.cpp
deleted file mode 100644
index e60651a..0000000
--- a/src/util/json/JsonWriter.cpp
+++ /dev/null
@@ -1,146 +0,0 @@
-// Copyright 2018, University of Freiburg,
-// Chair of Algorithms and Data Structures.
-// Authors: Patrick Brosi <brosi@informatik.uni-freiburg.de>
-
-#include <iomanip>
-#include "JsonWriter.h"
-#include "util/String.h"
-using namespace util;
-using namespace json;
-
-using std::ostream;
-using std::string;
-using std::map;
-
-// _____________________________________________________________________________
-JsonWriter::JsonWriter(std::ostream* out)
-    : _out(out), _pretty(false), _indent(2) {
-  *_out << std::setprecision(10);
-}
-
-// _____________________________________________________________________________
-JsonWriter::JsonWriter(std::ostream* out, size_t prec)
-    : _out(out), _pretty(false), _indent(2) {
-  *_out << std::setprecision(prec);
-}
-
-// _____________________________________________________________________________
-JsonWriter::JsonWriter(std::ostream* out, size_t prec, bool pret)
-    : _out(out), _pretty(pret), _indent(2) {
-  *_out << std::setprecision(prec);
-}
-
-// _____________________________________________________________________________
-JsonWriter::JsonWriter(std::ostream* out, size_t prec, bool pret, size_t indent)
-    : _out(out), _pretty(pret), _indent(indent) {
-  *_out << std::setprecision(prec);
-}
-
-// _____________________________________________________________________________
-void JsonWriter::obj() {
-  if (!_stack.empty() && _stack.top().type == OBJ)
-    throw JsonWriterException("Object not allowed as key");
-  if (!_stack.empty() && _stack.top().type == KEY) _stack.pop();
-  if (!_stack.empty() && _stack.top().type == ARR) valCheck();
-  if (_stack.size() && _stack.top().type == ARR) prettor();
-  (*_out) << "{";
-  _stack.push({OBJ, 1});
-}
-
-// _____________________________________________________________________________
-void JsonWriter::obj(const std::map<std::string, std::string> kvs) {
-  obj();
-  for (const auto& kv : kvs) {
-    key(kv.first);
-    val(kv.second);
-  }
-  close();
-}
-
-// _____________________________________________________________________________
-void JsonWriter::key(const std::string& k) {
-  if (_stack.empty() || _stack.top().type != OBJ)
-    throw JsonWriterException("Keys only allowed in objects.");
-  if (!_stack.top().empty) (*_out) << "," << (_pretty ? " " : "");
-  _stack.top().empty = 0;
-  prettor();
-  (*_out) << "\"" << k << "\""
-          << ":" << (_pretty ? " " : "");
-  _stack.push({KEY, 1});
-}
-
-// _____________________________________________________________________________
-void JsonWriter::keyVal(const std::string& k, const std::string& v) {
-  key(k);
-  val(v);
-}
-
-// _____________________________________________________________________________
-void JsonWriter::valCheck() {
-  if (_stack.empty() || (_stack.top().type != KEY && _stack.top().type != ARR))
-    throw JsonWriterException("Value not allowed here.");
-  if (!_stack.empty() && _stack.top().type == KEY) _stack.pop();
-  if (!_stack.empty() && _stack.top().type == ARR) {
-    if (!_stack.top().empty) (*_out) << "," << (_pretty ? " " : "");
-    _stack.top().empty = 0;
-  }
-}
-
-// _____________________________________________________________________________
-void JsonWriter::val(const std::string& v) {
-  valCheck();
-  (*_out) << "\"" << util::jsonStringEscape(v) << "\"";
-}
-
-// _____________________________________________________________________________
-void JsonWriter::val(int v) {
-  valCheck();
-  (*_out) << v;
-}
-
-// _____________________________________________________________________________
-void JsonWriter::val(double v) {
-  valCheck();
-  (*_out) << v;
-}
-
-// _____________________________________________________________________________
-void JsonWriter::arr() {
-  if (!_stack.empty() && _stack.top().type == OBJ)
-    throw JsonWriterException("Array not allowed as key");
-  if (!_stack.empty() && _stack.top().type == KEY) _stack.pop();
-  if (!_stack.empty() && _stack.top().type == ARR) valCheck();
-  (*_out) << "[";
-  _stack.push({ARR, 1});
-}
-
-// _____________________________________________________________________________
-void JsonWriter::prettor() {
-  if (_pretty) {
-    (*_out) << "\n";
-    for (size_t i = 0; i < _indent * _stack.size(); i++) (*_out) << " ";
-  }
-}
-
-// _____________________________________________________________________________
-void JsonWriter::closeAll() {
-  while (!_stack.empty()) close();
-}
-
-// _____________________________________________________________________________
-void JsonWriter::close() {
-  if (_stack.empty()) return;
-  switch (_stack.top().type) {
-    case OBJ:
-      _stack.pop();
-      prettor();
-      (*_out) << "}";
-      break;
-    case ARR:
-      _stack.pop();
-      (*_out) << "]";
-      break;
-    case KEY:
-      throw JsonWriterException("Missing value.");
-  }
-}
diff --git a/src/util/json/JsonWriter.h b/src/util/json/JsonWriter.h
deleted file mode 100644
index 82db149..0000000
--- a/src/util/json/JsonWriter.h
+++ /dev/null
@@ -1,70 +0,0 @@
-// Copyright 2018, University of Freiburg,
-// Chair of Algorithms and Data Structures.
-// Authors: Patrick Brosi <brosi@informatik.uni-freiburg.de>
-
-#ifndef UTIL_JSON_JSONWRITER_H_
-#define UTIL_JSON_JSONWRITER_H_
-
-#include <map>
-#include <ostream>
-#include <stack>
-#include <string>
-
-namespace util {
-namespace json {
-
-class JsonWriterException : public std::exception {
- public:
-  JsonWriterException(std::string msg) : _msg(msg) {}
-  ~JsonWriterException() throw() {}
-
-  virtual const char* what() const throw() { return _msg.c_str(); };
-
- private:
-  std::string _msg;
-};
-
-// simple JSON writer class without much overhead
-class JsonWriter {
- public:
-  explicit JsonWriter(std::ostream* out);
-  JsonWriter(std::ostream* out, size_t prec);
-  JsonWriter(std::ostream* out, size_t prec, bool pretty);
-  JsonWriter(std::ostream* out, size_t prec, bool pretty, size_t indent);
-  ~JsonWriter(){};
-
-  void obj();
-  void obj(const std::map<std::string, std::string> kvs);
-  void arr();
-  void key(const std::string& k);
-  void val(const std::string& v);
-  void val(int v);
-  void val(double v);
-  void keyVal(const std::string& k, const std::string& v);
-
-  void close();
-  void closeAll();
-
- private:
-  std::ostream* _out;
-
-  enum JSON_NODE_T { OBJ, ARR, KEY };
-
-  struct JsonNode {
-    JSON_NODE_T type;
-    bool empty;
-  };
-
-  std::stack<JsonNode> _stack;
-
-  bool _pretty;
-  size_t _indent;
-
-  void valCheck();
-  void prettor();
-};
-
-}  // namespace json
-}  // namespace util
-
-#endif  // UTIL_JSON_JSONWRITER_H_
diff --git a/src/util/tests/TestMain.cpp b/src/util/tests/TestMain.cpp
index 1037504..399bc21 100644
--- a/src/util/tests/TestMain.cpp
+++ b/src/util/tests/TestMain.cpp
@@ -7,6 +7,7 @@
 #include "util/Nullable.h"
 #include "util/String.h"
 #include "util/geo/Geo.h"
+#include "util/json/Writer.h"
 #include "util/graph/DirGraph.h"
 #include "util/graph/UndirGraph.h"
 #include "util/graph/Dijkstra.h"
@@ -36,6 +37,56 @@ CASE("atof") {
   // TODO: more test cases
 }},
 
+// ___________________________________________________________________________
+{
+CASE("json") {
+  std::stringstream ss;
+  util::json::Writer wr(&ss, 2, false);
+
+  util::json::Val a("bla");
+  util::json::Val b(1);
+  util::json::Val c(1.0);
+  util::json::Val d("a");
+  util::json::Val e({"a", "b", "c"});
+
+  util::json::Val f({1, json::Array{2, 3, 4}, 3});
+
+  ss = std::stringstream();
+  wr = util::json::Writer(&ss, 2, false);
+  util::json::Val i({1, json::Array{2, json::Null(), 4}, true});
+  wr.val(i);
+  wr.closeAll();
+  EXPECT(ss.str() == "[1,[2,null,4],true]");
+
+  ss = std::stringstream();
+  wr = util::json::Writer(&ss, 2, false);
+  i = util::json::Val({1, json::Array{2, json::Null(), 4}, false});
+  wr.val(i);
+  wr.closeAll();
+  EXPECT(ss.str() == "[1,[2,null,4],false]");
+
+  ss = std::stringstream();
+  wr = util::json::Writer(&ss, 2, false);
+  i = util::json::Val({1, json::Array{2, json::Null(), 4}, false});
+  wr.val(i);
+  wr.closeAll();
+  EXPECT(ss.str() == "[1,[2,null,4],false]");
+
+  ss = std::stringstream();
+  wr = util::json::Writer(&ss, 2, false);
+  i = util::json::Val({1, json::Array{2.13, "", 4}, 0});
+  wr.val(i);
+  wr.closeAll();
+  EXPECT(ss.str() == "[1,[2.13,\"\",4],0]");
+
+  ss = std::stringstream();
+  wr = util::json::Writer(&ss, 2, false);
+  i = util::json::Val({1, json::Array{2.13, json::Dict{{"a", 1}, {"B", 2.123}}, 4}, 0});
+  wr.val(i);
+  wr.closeAll();
+  EXPECT((ss.str() == "[1,[2.13,{\"a\":1,\"B\":2.12},4],0]" || ss.str() == "[1,[2.13,{\"B\":2.12,\"a\":1},4],0]"));
+}},
+
 // ___________________________________________________________________________
 {
 CASE("dirgraph") {