diff --git a/vpr/src/base/route_constraint.cpp b/vpr/src/base/route_constraint.cpp_back
similarity index 100%
rename from vpr/src/base/route_constraint.cpp
rename to vpr/src/base/route_constraint.cpp_back
diff --git a/vpr/src/base/route_constraint.h b/vpr/src/base/route_constraint.h_back
similarity index 100%
rename from vpr/src/base/route_constraint.h
rename to vpr/src/base/route_constraint.h_back
diff --git a/vpr/src/base/vpr_api.cpp b/vpr/src/base/vpr_api.cpp
index 0deedc7674f..ed3c68b8603 100644
--- a/vpr/src/base/vpr_api.cpp
+++ b/vpr/src/base/vpr_api.cpp
@@ -421,9 +421,6 @@ bool vpr_flow(t_vpr_setup& vpr_setup, t_arch& arch) {
         vpr_analysis_flow(router_net_list, vpr_setup, arch, route_status, is_flat);
     }
 
-    // write out constratins
-    write_vpr_constraints(vpr_setup);
-
     //close the graphics
     vpr_close_graphics(vpr_setup);
 
diff --git a/vpr/src/base/vpr_constraints.cpp_back b/vpr/src/base/vpr_constraints.cpp_back
new file mode 100644
index 00000000000..9ae678c94e0
--- /dev/null
+++ b/vpr/src/base/vpr_constraints.cpp_back
@@ -0,0 +1,18 @@
+#include "vpr_constraints.h"
+
+
+UserPlaceConstraints& VprConstraints::mutable_place_constraints() {
+    return placement_constraints_;
+}
+
+UserRouteConstraints& VprConstraints::mutable_route_constraints() {
+    return route_constraints_;
+}
+
+const UserPlaceConstraints& VprConstraints::place_constraints() const {
+    return placement_constraints_;
+}
+
+const UserRouteConstraints& VprConstraints::route_constraints() const {
+    return route_constraints_;
+}
diff --git a/vpr/src/base/vpr_constraints.h b/vpr/src/base/vpr_constraints.h
index afb9da92c79..6ac53af783b 100644
--- a/vpr/src/base/vpr_constraints.h
+++ b/vpr/src/base/vpr_constraints.h
@@ -51,21 +51,21 @@ class VprConstraints {
      *
      *   @param net_name the route constraint 
      */
-    void add_route_constraint(RouteConstraint rc);
+    void add_route_constraint(UserRouteConstraints rc);
 
     /**
      * @brief returns route constraint by index
      *
      *   @param index the constraint index 
      */
-    const RouteConstraint get_route_constraint_by_idx(std::size_t index) const;
+    const UserRouteConstraints get_route_constraint_by_idx(std::size_t index) const;
 
     /**
      * @brief returns route constraint of a specific net
      *
      *   @param net_name the net name
      */
-    const RouteConstraint get_route_constraint_by_net_name(std::string net_name);
+    const UserRouteConstraints get_route_constraint_by_net_name(std::string net_name);
 
     /**
      * @brief returns number of route constraints
diff --git a/vpr/src/base/vpr_constraints_reader.cpp b/vpr/src/base/vpr_constraints_reader.cpp
index cd0c39785b0..9bb8dccf9bd 100644
--- a/vpr/src/base/vpr_constraints_reader.cpp
+++ b/vpr/src/base/vpr_constraints_reader.cpp
@@ -10,51 +10,26 @@
 
 #include <fstream>
 #include "vpr_constraints_reader.h"
-#include "vtr_token.h"
 
 void load_vpr_constraints_file(const char* read_vpr_constraints_name) {
     vtr::ScopedStartFinishTimer timer("Reading VPR constraints from " + std::string(read_vpr_constraints_name));
 
     VprConstraintsSerializer reader;
 
-    // file name from arguments could be a serial of files, seperated by colon ":"
-    // at this point, caller has already checked that the required constraint file name is not emtpy
-    int num_tokens = 0, num_file_read = 0;
-    bool found_file = false;
-    t_token* tokens = GetTokensFromString(read_vpr_constraints_name, &num_tokens);
-    std::string in_tokens("");
-    for (int i = 0; i < num_tokens; i++) {
-        if ((tokens[i].type == TOKEN_COLON)) { // end of one input file
-            found_file = true;
-        } else if (i == num_tokens - 1) { // end of inputs, append token anyway
-            in_tokens += std::string(tokens[i].data);
-            found_file = true;
-        } else {
-            in_tokens += std::string(tokens[i].data);
-        }
-        if (found_file) {
-            const char* file_name = in_tokens.c_str();
-            if (vtr::check_file_name_extension(file_name, ".xml")) {
-                try {
-                    std::ifstream file(file_name);
-                    void* context;
-                    uxsd::load_vpr_constraints_xml(reader, context, file_name, file);
-                } catch (pugiutil::XmlError& e) {
-                    vpr_throw(VPR_ERROR_ROUTE, file_name, e.line(), "%s", e.what());
-                }
-            } else {
-                VTR_LOG_WARN(
-                    "VPR constraints file '%s' may be in incorrect format. "
-                    "Expecting .xml format. Not reading file.\n",
-                    file_name);
-            }
-            in_tokens.clear();
-            num_file_read++;
-            found_file = false;
+    if (vtr::check_file_name_extension(read_vpr_constraints_name, ".xml")) {
+        try {
+            std::ifstream file(read_vpr_constraints_name);
+            void* context;
+            uxsd::load_vpr_constraints_xml(reader, context, read_vpr_constraints_name, file);
+        } catch (pugiutil::XmlError& e) {
+            vpr_throw(VPR_ERROR_ROUTE, read_vpr_constraints_name, e.line(), "%s", e.what());
         }
+    } else {
+        VTR_LOG_WARN(
+            "VPR constraints file '%s' may be in incorrect format. "
+            "Expecting .xml format. Not reading file.\n",
+            read_vpr_constraints_name);
     }
-    VTR_LOG("Read in '%d' constraint file(s) successfully.\n", num_file_read);
-    freeTokens(tokens, num_tokens);
 
     //Update the floorplanning constraints in the floorplanning constraints context
     auto& floorplanning_ctx = g_vpr_ctx.mutable_floorplanning();
diff --git a/vpr/src/base/vpr_constraints_reader.h b/vpr/src/base/vpr_constraints_reader.h
index 130baabc720..9740825836d 100644
--- a/vpr/src/base/vpr_constraints_reader.h
+++ b/vpr/src/base/vpr_constraints_reader.h
@@ -5,6 +5,6 @@
 #ifndef VPR_CONSTRAINTS_READER_H_
 #define VPR_CONSTRAINTS_READER_H_
 
-void load_vpr_constraints_files(const char* read_vpr_constraints_name);
+void load_vpr_constraints_file(const char* read_vpr_constraints_name);
 
 #endif /* VPR_CONSTRAINTS_READER_H_ */
diff --git a/vpr/src/base/vpr_constraints_serializer.h b/vpr/src/base/vpr_constraints_serializer.h
index 3f95b78b6e4..9ab4c3bd96f 100644
--- a/vpr/src/base/vpr_constraints_serializer.h
+++ b/vpr/src/base/vpr_constraints_serializer.h
@@ -2,7 +2,6 @@
 #define VPR_CONSTRAINTS_SERIALIZER_H_
 
 #include "region.h"
-#include "route_constraint.h"
 #include "vpr_constraints.h"
 #include "partition.h"
 #include "partition_region.h"
@@ -442,53 +441,21 @@ class VprConstraintsSerializer final : public uxsd::VprConstraintsBase<VprConstr
         return temp_.c_str();
     }
 
-    virtual inline void set_vpr_constraints_tool_name(const char* /*tool_name*/, void*& /*ctx*/) final {
-    }
+    virtual inline void set_vpr_constraints_tool_name(const char* /*tool_name*/, void*& /*ctx*/) final {}
 
     virtual inline void set_vpr_constraints_constraints_comment(const char* /*constraints_comment*/, void*& /*ctx*/) final {}
 
     virtual inline const char* get_vpr_constraints_constraints_comment(void*& /*ctx*/) final {
         return temp_.c_str();
     }
-
-    virtual inline void preallocate_vpr_constraints_partition_list(void*& /*ctx*/, size_t) final {
-    }
-
-    virtual inline void* add_vpr_constraints_partition_list(void*& /*ctx*/) final {
+    virtual inline void* init_vpr_constraints_partition_list(void*& /*ctx*/) final {
         return nullptr;
     }
 
     virtual inline void finish_vpr_constraints_partition_list(void*& /*ctx*/) final {
-        return;
     }
 
-    virtual inline size_t num_vpr_constraints_partition_list(void*& /*ctx*/) final {
-        // only one or zero partion list is supported
-        if (constraints_.get_num_partitions()) {
-            return 1;
-        }
-        return 0;
-    }
-
-    virtual inline void* get_vpr_constraints_partition_list(int, void*& /*ctx*/) final {
-        return nullptr;
-    }
-
-    virtual inline void preallocate_vpr_constraints_global_route_constraints(void*& /*ctx*/, size_t) final {
-    }
-
-    virtual inline void* add_vpr_constraints_global_route_constraints(void*& /*ctx*/) final {
-        return nullptr;
-    }
-
-    virtual inline void finish_vpr_constraints_global_route_constraints(void*& /*ctx*/) final {
-        return;
-    }
-    virtual inline size_t num_vpr_constraints_global_route_constraints(void*& /*ctx*/) final {
-        return constraints_.get_route_constraint_num();
-    }
-
-    virtual inline void* get_vpr_constraints_global_route_constraints(int, void*& /*cts*/) final {
+    virtual inline void* get_vpr_constraints_partition_list(void*& /*ctx*/) final {
         return nullptr;
     }
 
@@ -499,7 +466,6 @@ class VprConstraintsSerializer final : public uxsd::VprConstraintsBase<VprConstr
             return false;
     }
     virtual void finish_load() final {
-        return;
     }
 
     //temp data for writes
diff --git a/vpr/src/base/vpr_constraints_writer.cpp b/vpr/src/base/vpr_constraints_writer.cpp
index 1db5563de05..b1e50917ae1 100644
--- a/vpr/src/base/vpr_constraints_writer.cpp
+++ b/vpr/src/base/vpr_constraints_writer.cpp
@@ -20,50 +20,6 @@
 #include "region.h"
 #include "re_cluster_util.h"
 
-void write_vpr_constraints(t_vpr_setup& vpr_setup) {
-    auto& filename_opts = vpr_setup.FileNameOpts;
-    if (!filename_opts.write_vpr_constraints_file.empty()) {
-        std::string file_name = filename_opts.write_vpr_constraints_file;
-        if (vtr::check_file_name_extension(file_name.c_str(), ".xml")) {
-            VprConstraints constraints;
-
-            // update constraints with place info
-            // this is to align to original place/partion constraint behavior
-            const auto& placer_opts = vpr_setup.PlacerOpts;
-            int horizontal_partitions = placer_opts.floorplan_num_horizontal_partitions, vertical_partitions = placer_opts.floorplan_num_vertical_partitions;
-            if (horizontal_partitions != 0 && vertical_partitions != 0) {
-                setup_vpr_floorplan_constraints_cutpoints(constraints, horizontal_partitions, vertical_partitions);
-            } else {
-                setup_vpr_floorplan_constraints_one_loc(constraints, placer_opts.place_constraint_expand, placer_opts.place_constraint_subtile);
-            }
-
-            // update route constraints
-            for (int i = 0; i < g_vpr_ctx.routing().constraints.get_route_constraint_num(); i++) {
-                RouteConstraint rc = g_vpr_ctx.routing().constraints.get_route_constraint_by_idx(i);
-                // note: route constraints with regexpr in input constraint file
-                // is now replaced with the real net name and will not be written
-                // into output file
-                if (rc.is_valid()) {
-                    constraints.add_route_constraint(rc);
-                }
-            }
-
-            // VprConstraintsSerializer writer(g_vpr_ctx.routing().constraints);
-            VprConstraintsSerializer writer(constraints);
-            std::fstream fp;
-            fp.open(file_name.c_str(), std::fstream::out | std::fstream::trunc);
-            fp.precision(std::numeric_limits<float>::max_digits10);
-            void* context;
-            uxsd::write_vpr_constraints_xml(writer, context, fp);
-        } else {
-            VPR_FATAL_ERROR(VPR_ERROR_ROUTE,
-                            "Unknown extension on output %s",
-                            file_name.c_str());
-        }
-    }
-    return;
-}
-
 void write_vpr_floorplan_constraints(const char* file_name, int expand, bool subtile, int horizontal_partitions, int vertical_partitions) {
     VprConstraints constraints;
 
diff --git a/vpr/src/tileable_rr_graph/tileable_rr_graph_builder.cpp b/vpr/src/tileable_rr_graph/tileable_rr_graph_builder.cpp
index e22ac4d63a8..58d58e27226 100644
--- a/vpr/src/tileable_rr_graph/tileable_rr_graph_builder.cpp
+++ b/vpr/src/tileable_rr_graph/tileable_rr_graph_builder.cpp
@@ -316,7 +316,7 @@ void build_tileable_unidir_rr_graph(const std::vector<t_physical_tile_type>& typ
     }
 
     /* No clock network support yet; Does not support flatten rr_graph yet */
-    check_rr_graph(device_ctx.rr_graph, types, device_ctx.rr_indexed_data, grids, device_ctx.chan_width, GRAPH_UNIDIR, OPEN, false);
+    check_rr_graph(device_ctx.rr_graph, types, device_ctx.rr_indexed_data, grids, device_ctx.chan_width, GRAPH_UNIDIR, false);
 
     /************************************************************************
      * Free all temp stucts
diff --git a/vpr/src/util/vpr_utils.cpp b/vpr/src/util/vpr_utils.cpp
index eac7d9d7087..b995c4da985 100644
--- a/vpr/src/util/vpr_utils.cpp
+++ b/vpr/src/util/vpr_utils.cpp
@@ -2289,22 +2289,6 @@ bool is_inter_cluster_node(const RRGraphView& rr_graph_view,
     }
 }
 
-void apply_route_constraints(VprConstraints& vpr_constraint) {
-    ClusteringContext& mutable_cluster_ctx = g_vpr_ctx.mutable_clustering();
-    for (auto net_id : mutable_cluster_ctx.clb_nlist.nets()) {
-        std::string net_name = mutable_cluster_ctx.clb_nlist.net_name(net_id);
-        const RouteConstraint rc = vpr_constraint.get_route_constraint_by_net_name(net_name);
-        if (rc.is_valid()) {
-            mutable_cluster_ctx.clb_nlist.set_net_is_global(net_id, true);
-            if (rc.route_model() == "route") {
-                mutable_cluster_ctx.clb_nlist.set_net_is_ignored(net_id, false);
-            } else {
-                mutable_cluster_ctx.clb_nlist.set_net_is_ignored(net_id, true);
-            }
-        }
-    }
-}
-
 int get_rr_node_max_ptc(const RRGraphView& rr_graph_view,
                         RRNodeId node_id,
                         bool is_flat) {