diff --git a/design_introspection-plugin/get_pins.cc b/design_introspection-plugin/get_pins.cc
index f57662d..aa557e8 100644
--- a/design_introspection-plugin/get_pins.cc
+++ b/design_introspection-plugin/get_pins.cc
@@ -6,33 +6,28 @@
 
 std::string GetPins::SelectionType() { return "c"; }
 
-void GetPins::execute(std::vector<std::string> args, RTLIL::Design* design) {
-    if (design->top_module() == nullptr) {
-	log_cmd_error("No top module detected\n");
-    }
+void GetPins::ExecuteSelection([[gnu::unused]] RTLIL::Design* design,
+                               [[gnu::unused]] const CommandArgs& args) {
+}
 
-    CommandArgs parsed_args(ParseCommand(args));
-    Tcl_Obj* tcl_list = Tcl_NewListObj(0, NULL);
-    for (auto obj : parsed_args.selection_objects) {
+GetPins::SelectionObjects GetPins::ExtractSelection(RTLIL::Design* design, const CommandArgs& args) {
+    SelectionObjects selection_objects;
+    for (auto obj : args.selection_objects) {
 	size_t port_separator = obj.find_last_of("/");
 	std::string cell = obj.substr(0, port_separator);
 	std::string port = obj.substr(port_separator + 1);
 	SelectionObjects selection{RTLIL::unescape_id(design->top_module()->name) + "/" +
 	       SelectionType() + ":" + cell};
 	extra_args(selection, 0, design);
-	ExtractSingleSelection(tcl_list, design, port, parsed_args);
+	ExtractSingleSelection(selection_objects, design, port, args);
     }
-    if (!parsed_args.is_quiet) {
+    if (!args.is_quiet) {
 	log("\n");
     }
-    Tcl_SetObjResult(yosys_get_tcl_interp(), tcl_list);
+    return selection_objects;
 }
 
-GetPins::SelectionObjects GetPins::ExtractSelection(RTLIL::Design* design, const CommandArgs& args) {
-    return SelectionObjects();
-}
-
-void GetPins::ExtractSingleSelection(Tcl_Obj* tcl_list, RTLIL::Design* design,
+void GetPins::ExtractSingleSelection(SelectionObjects& objects, RTLIL::Design* design,
                                      const std::string& port_name,
                                      const CommandArgs& args) {
     if (design->selected_modules().empty()) {
@@ -58,9 +53,7 @@
 	    if (!args.is_quiet) {
 		log("%s ", pin_name.c_str());
 	    }
-	    Tcl_Obj* value_obj = Tcl_NewStringObj(pin_name.c_str(), -1);
-	    Tcl_ListObjAppendElement(yosys_get_tcl_interp(), tcl_list,
-	                             value_obj);
+	    objects.push_back(pin_name);
 	}
     }
 }
diff --git a/design_introspection-plugin/get_pins.h b/design_introspection-plugin/get_pins.h
index ab5bf75..57a619d 100644
--- a/design_introspection-plugin/get_pins.h
+++ b/design_introspection-plugin/get_pins.h
@@ -11,10 +11,12 @@
    private:
     std::string TypeName() override;
     std::string SelectionType() override;
-    void execute(std::vector<std::string> args, RTLIL::Design* design) override;
     SelectionObjects ExtractSelection(RTLIL::Design* design,
                                       const CommandArgs& args) override;
-    void ExtractSingleSelection(Tcl_Obj* tcl_list, RTLIL::Design* design,
+    void ExecuteSelection(RTLIL::Design* design,
+                          const CommandArgs& args) override;
+    void ExtractSingleSelection(SelectionObjects& objects,
+                                RTLIL::Design* design,
                                 const std::string& port_name,
                                 const CommandArgs& args);
 };
diff --git a/design_introspection-plugin/get_ports.cc b/design_introspection-plugin/get_ports.cc
index 8c60712..be9e7f3 100644
--- a/design_introspection-plugin/get_ports.cc
+++ b/design_introspection-plugin/get_ports.cc
@@ -6,20 +6,13 @@
 
 std::string GetPorts::SelectionType() { return "x"; }
 
-GetPorts::SelectionObjects GetPorts::ExtractSelection(RTLIL::Design* design, const CommandArgs& args) {
-    return SelectionObjects();
+void GetPorts::ExecuteSelection([[gnu::unused]] RTLIL::Design* design,
+                               [[gnu::unused]] const CommandArgs& args) {
 }
 
-void GetPorts::execute(std::vector<std::string> args, RTLIL::Design* design) {
-    if (args.size() < 2) {
-	log_cmd_error("No port specified.\n");
-    }
-    RTLIL::Module* top_module = design->top_module();
-    if (top_module == nullptr) {
-	log_cmd_error("No top module detected\n");
-    }
-    // TODO handle more than one port
-    std::string port_name = args.at(1);
+GetPorts::SelectionObjects GetPorts::ExtractSelection(RTLIL::Design* design,
+                                                      const CommandArgs& args) {
+    std::string port_name = args.selection_objects.at(0);
     std::string port_str(port_name.size(), '\0');
     int bit(0);
     if (!sscanf(port_name.c_str(), "%[^[][%d]", &port_str[0], &bit)) {
@@ -28,17 +21,21 @@
 
     port_str.resize(strlen(port_str.c_str()));
     RTLIL::IdString port_id(RTLIL::escape_id(port_str));
-    Tcl_Interp* interp = yosys_get_tcl_interp();
-    if (auto wire = top_module->wire(port_id)) {
+    SelectionObjects objects;
+    if (auto wire = design->top_module()->wire(port_id)) {
 	if (wire->port_input || wire->port_output) {
 	    if (bit >= wire->start_offset &&
 	        bit < wire->start_offset + wire->width) {
-		Tcl_Obj* tcl_string = Tcl_NewStringObj(port_name.c_str(), -1);
-		Tcl_SetObjResult(interp, tcl_string);
-		log("Found port %s\n", port_name.c_str());
-		return;
+		objects.push_back(port_name);
+		if (!args.is_quiet) {
+		    log("%s ", port_name.c_str());
+		}
 	    }
 	}
     }
-    log_error("Couldn't find port %s\n", port_name.c_str());
+    if (objects.size() == 0 and !args.is_quiet) {
+	log_error("Couldn't find port %s\n", port_name.c_str());
+    }
+    return objects;
 }
+
diff --git a/design_introspection-plugin/get_ports.h b/design_introspection-plugin/get_ports.h
index 7a66d6d..4e66b36 100644
--- a/design_introspection-plugin/get_ports.h
+++ b/design_introspection-plugin/get_ports.h
@@ -11,9 +11,11 @@
    private:
     std::string TypeName() override;
     std::string SelectionType() override;
-    void execute(std::vector<std::string> args, RTLIL::Design* design) override;
+    /* void execute(std::vector<std::string> args, RTLIL::Design* design) override; */
     SelectionObjects ExtractSelection(RTLIL::Design* design,
                                       const CommandArgs& args) override;
+    void ExecuteSelection(RTLIL::Design* design,
+                          const CommandArgs& args) override;
 };
 
 #endif  // GET_PORTS_H_