diff --git a/src/operation/iCTS/api/CTSAPI.cc b/src/operation/iCTS/api/CTSAPI.cc
index dfa84c6cee7aa0236576a9f2c778eb9489964386..8e04b81994352b0093684392daf86e8b40f9151d 100644
--- a/src/operation/iCTS/api/CTSAPI.cc
+++ b/src/operation/iCTS/api/CTSAPI.cc
@@ -96,7 +96,6 @@ void CTSAPI::writeDB()
 
 void CTSAPI::writeGDS()
 {
-  writeSkewMap();
   GDSPloter::plotDesign();
   GDSPloter::plotFlyLine();
   GDSPloter::writePyDesign();
@@ -1173,22 +1172,5 @@ ieda_feature::CTSSummary CTSAPI::outputSummary()
   return summary;
 }
 
-void CTSAPI::writeSkewMap() const
-{
-  auto* ista = _timing_engine->get_ista();
-  auto& clocks = ista->get_clocks();
-
-  for (auto& clock : clocks) {
-    StaBuildClockTree build_clock_tree;
-    build_clock_tree(clock.get());
-
-    auto base_path = _config->get_output_def_path() + "/" + std::string(clock->get_clock_name());
-
-    auto& clock_trees = build_clock_tree.takeClockTrees();
-    clock_trees.front()->printInstGraphViz((base_path + "_skewmap.dot").c_str(), false);
-    clock_trees.front()->printInstJson((base_path + "_skewmap.json").c_str(), false);
-    clock_trees.clear();
-  }
-}
 
 }  // namespace icts
\ No newline at end of file
diff --git a/src/operation/iCTS/api/CTSAPI.hh b/src/operation/iCTS/api/CTSAPI.hh
index ee561031f27152756301014a2dc0792d966864f6..5072c06237be43ffaa01f5a3ec721effae7d74bc 100644
--- a/src/operation/iCTS/api/CTSAPI.hh
+++ b/src/operation/iCTS/api/CTSAPI.hh
@@ -201,7 +201,6 @@ class CTSAPI
   double getCapacitance(const double& wire_length, const int& level) const;
   double getResistance(const double& wire_length, const int& level) const;
   ista::TimingIDBAdapter* getStaDbAdapter() const;
-  void writeSkewMap() const;
 
   // variable
   icts::CtsConfig* _config = nullptr;
diff --git a/src/operation/iCTS/source/data_manager/io/GDSPloter.cc b/src/operation/iCTS/source/data_manager/io/GDSPloter.cc
index 817e74a407f48e7a0ccc8b061eb281b59b2b023e..a8db98e86dcaf7293b596668274a542ec2623eb8 100644
--- a/src/operation/iCTS/source/data_manager/io/GDSPloter.cc
+++ b/src/operation/iCTS/source/data_manager/io/GDSPloter.cc
@@ -461,7 +461,25 @@ void GDSPloter::writeJsonDesign(const std::string& path)
 
       wires.push_back(wire_obj);
     }
-    net["wires"] = wires;
+    net["wires_layout"] = wires;
+
+    // Add delay information
+    nlohmann::json delays = nlohmann::json::array();
+
+    // Only consider a single clock source for now.
+    auto clk_port = design->get_clocks().front()->get_clock_name();
+    
+    for (auto& p : clk_net->get_load_pins()) {
+      auto delay = CTSAPIInst.getClockAT(p->get_full_name(), clk_port);
+      auto driver = clk_net->get_driver_pin();
+
+      nlohmann::json delay_obj;
+      delay_obj["from"] = driver->get_full_name();
+      delay_obj["to"] = p->get_full_name();
+      delay_obj["delay"] = delay;
+      delays.push_back(delay_obj);
+    }
+    net["wires_delay"] = delays;
 
     nets.push_back(net);
   }