diff --git a/SchemeEditor.pro.user b/SchemeEditor.pro.user
index 2130b65..8d07bd2 100644
--- a/SchemeEditor.pro.user
+++ b/SchemeEditor.pro.user
@@ -1,10 +1,10 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!DOCTYPE QtCreatorProject>
-<!-- Written by QtCreator 7.0.0, 2022-04-12T22:39:08. -->
+<!-- Written by QtCreator 6.0.2, 2022-04-18T11:25:49. -->
 <qtcreator>
  <data>
   <variable>EnvironmentId</variable>
-  <value type="QByteArray">{1f5ef7b0-cf08-4d4a-b37d-18ed0b7a2084}</value>
+  <value type="QByteArray">{391729b0-9fcc-4b56-ba51-7d7ee685fc97}</value>
  </data>
  <data>
   <variable>ProjectExplorer.Project.ActiveTarget</variable>
@@ -83,22 +83,25 @@
     <valuelist type="QVariantList" key="ClangTools.SuppressedDiagnostics"/>
     <value type="bool" key="ClangTools.UseGlobalSettings">true</value>
    </valuemap>
+   <valuemap type="QVariantMap" key="CppEditor.QuickFix">
+    <value type="bool" key="UseGlobalSettings">true</value>
+   </valuemap>
   </valuemap>
  </data>
  <data>
   <variable>ProjectExplorer.Project.Target.0</variable>
   <valuemap type="QVariantMap">
    <value type="QString" key="DeviceType">Desktop</value>
-   <value type="QString" key="ProjectExplorer.ProjectConfiguration.DefaultDisplayName">Desktop Qt 5.15.2 clang 64bit</value>
-   <value type="QString" key="ProjectExplorer.ProjectConfiguration.DisplayName">Desktop Qt 5.15.2 clang 64bit</value>
-   <value type="QString" key="ProjectExplorer.ProjectConfiguration.Id">qt.qt5.5152.clang_64_kit</value>
+   <value type="QString" key="ProjectExplorer.ProjectConfiguration.DefaultDisplayName">Desktop</value>
+   <value type="QString" key="ProjectExplorer.ProjectConfiguration.DisplayName">Desktop</value>
+   <value type="QString" key="ProjectExplorer.ProjectConfiguration.Id">{8ccd2350-ba56-4630-b9a6-4b0b4b193aaf}</value>
    <value type="qlonglong" key="ProjectExplorer.Target.ActiveBuildConfiguration">0</value>
    <value type="qlonglong" key="ProjectExplorer.Target.ActiveDeployConfiguration">0</value>
    <value type="qlonglong" key="ProjectExplorer.Target.ActiveRunConfiguration">0</value>
    <valuemap type="QVariantMap" key="ProjectExplorer.Target.BuildConfiguration.0">
     <value type="int" key="EnableQmlDebugging">0</value>
-    <value type="QString" key="ProjectExplorer.BuildConfiguration.BuildDirectory">/Users/s2ismac/Desktop/comdel/build-SchemeEditor-Desktop_Qt_5_15_2_clang_64bit-Debug</value>
-    <value type="QString" key="ProjectExplorer.BuildConfiguration.BuildDirectory.shadowDir">/Users/s2ismac/Desktop/comdel/build-SchemeEditor-Desktop_Qt_5_15_2_clang_64bit-Debug</value>
+    <value type="QString" key="ProjectExplorer.BuildConfiguration.BuildDirectory">/home/bbr/build-SchemeEditor-Desktop-Debug</value>
+    <value type="QString" key="ProjectExplorer.BuildConfiguration.BuildDirectory.shadowDir">/home/bbr/build-SchemeEditor-Desktop-Debug</value>
     <valuemap type="QVariantMap" key="ProjectExplorer.BuildConfiguration.BuildStepList.0">
      <valuemap type="QVariantMap" key="ProjectExplorer.BuildStepList.Step.0">
       <value type="bool" key="ProjectExplorer.BuildStep.Enabled">true</value>
@@ -136,8 +139,8 @@
     <value type="int" key="Qt4ProjectManager.Qt4BuildConfiguration.BuildConfiguration">2</value>
    </valuemap>
    <valuemap type="QVariantMap" key="ProjectExplorer.Target.BuildConfiguration.1">
-    <value type="QString" key="ProjectExplorer.BuildConfiguration.BuildDirectory">/Users/s2ismac/Desktop/comdel/build-SchemeEditor-Desktop_Qt_5_15_2_clang_64bit-Release</value>
-    <value type="QString" key="ProjectExplorer.BuildConfiguration.BuildDirectory.shadowDir">/Users/s2ismac/Desktop/comdel/build-SchemeEditor-Desktop_Qt_5_15_2_clang_64bit-Release</value>
+    <value type="QString" key="ProjectExplorer.BuildConfiguration.BuildDirectory">/home/bbr/build-SchemeEditor-Desktop-Release</value>
+    <value type="QString" key="ProjectExplorer.BuildConfiguration.BuildDirectory.shadowDir">/home/bbr/build-SchemeEditor-Desktop-Release</value>
     <valuemap type="QVariantMap" key="ProjectExplorer.BuildConfiguration.BuildStepList.0">
      <valuemap type="QVariantMap" key="ProjectExplorer.BuildStepList.Step.0">
       <value type="bool" key="ProjectExplorer.BuildStep.Enabled">true</value>
@@ -177,8 +180,8 @@
    </valuemap>
    <valuemap type="QVariantMap" key="ProjectExplorer.Target.BuildConfiguration.2">
     <value type="int" key="EnableQmlDebugging">0</value>
-    <value type="QString" key="ProjectExplorer.BuildConfiguration.BuildDirectory">/Users/s2ismac/Desktop/comdel/build-SchemeEditor-Desktop_Qt_5_15_2_clang_64bit-Profile</value>
-    <value type="QString" key="ProjectExplorer.BuildConfiguration.BuildDirectory.shadowDir">/Users/s2ismac/Desktop/comdel/build-SchemeEditor-Desktop_Qt_5_15_2_clang_64bit-Profile</value>
+    <value type="QString" key="ProjectExplorer.BuildConfiguration.BuildDirectory">/home/bbr/build-SchemeEditor-Desktop-Profile</value>
+    <value type="QString" key="ProjectExplorer.BuildConfiguration.BuildDirectory.shadowDir">/home/bbr/build-SchemeEditor-Desktop-Profile</value>
     <valuemap type="QVariantMap" key="ProjectExplorer.BuildConfiguration.BuildStepList.0">
      <valuemap type="QVariantMap" key="ProjectExplorer.BuildStepList.Step.0">
       <value type="bool" key="ProjectExplorer.BuildStep.Enabled">true</value>
@@ -238,14 +241,14 @@
     <valuelist type="QVariantList" key="CustomOutputParsers"/>
     <value type="int" key="PE.EnvironmentAspect.Base">2</value>
     <valuelist type="QVariantList" key="PE.EnvironmentAspect.Changes"/>
-    <value type="QString" key="ProjectExplorer.ProjectConfiguration.Id">Qt4ProjectManager.Qt4RunConfiguration:/Users/s2ismac/Desktop/comdel/schema_editor/SchemeEditor.pro</value>
-    <value type="QString" key="ProjectExplorer.RunConfiguration.BuildKey">/Users/s2ismac/Desktop/comdel/schema_editor/SchemeEditor.pro</value>
+    <value type="QString" key="ProjectExplorer.ProjectConfiguration.Id">Qt4ProjectManager.Qt4RunConfiguration:/home/bbr/SchemeEditor/SchemeEditor.pro</value>
+    <value type="QString" key="ProjectExplorer.RunConfiguration.BuildKey">/home/bbr/SchemeEditor/SchemeEditor.pro</value>
     <value type="bool" key="RunConfiguration.UseCppDebugger">false</value>
     <value type="bool" key="RunConfiguration.UseCppDebuggerAuto">true</value>
     <value type="bool" key="RunConfiguration.UseLibrarySearchPath">true</value>
     <value type="bool" key="RunConfiguration.UseQmlDebugger">false</value>
     <value type="bool" key="RunConfiguration.UseQmlDebuggerAuto">true</value>
-    <value type="QString" key="RunConfiguration.WorkingDirectory.default">/Users/s2ismac/Desktop/comdel/build-SchemeEditor-Desktop_Qt_5_15_2_clang_64bit-Debug/SchemeEditor.app/Contents/MacOS</value>
+    <value type="QString" key="RunConfiguration.WorkingDirectory.default">/home/bbr/build-SchemeEditor-Desktop-Debug</value>
    </valuemap>
    <value type="qlonglong" key="ProjectExplorer.Target.RunConfigurationCount">1</value>
   </valuemap>
diff --git a/comdel/display/schema_display.cpp b/comdel/display/schema_display.cpp
index 7b18878..6564d36 100644
--- a/comdel/display/schema_display.cpp
+++ b/comdel/display/schema_display.cpp
@@ -9,11 +9,11 @@ Schema::Schema()
 }
 
 
-void Schema::setSchema(std::optional<domain::Schema> schema)
+void Schema::setSchema(domain::Schema* schema)
 {
     scene.clear();
     this->schema = schema;
-    if(schema.has_value()) {
+    if(schema != nullptr) {
         for(auto &instance: schema->instances) {
             ComponentWrapper *group = nullptr;
             auto component = dynamic_cast<domain::ComponentInstance*>(instance);
diff --git a/comdel/display/schema_display.h b/comdel/display/schema_display.h
index 6acd574..2e60997 100644
--- a/comdel/display/schema_display.h
+++ b/comdel/display/schema_display.h
@@ -14,12 +14,12 @@ class Schema: public QGraphicsView
 public:
     Schema();
 
-    void setSchema(std::optional<domain::Schema> schema);
+    void setSchema(domain::Schema* schema);
 
 private:
     QGraphicsScene scene;
 
-    std::optional<domain::Schema> schema;
+    domain::Schema* schema;
 
 };
 
diff --git a/comdel/domain/schemacreator.cpp b/comdel/domain/schemacreator.cpp
index 572700c..eae4383 100644
--- a/comdel/domain/schemacreator.cpp
+++ b/comdel/domain/schemacreator.cpp
@@ -728,28 +728,28 @@ std::optional<Condition> SchemaCreator::loadCondition(ConditionNode node)
 }
 
 
-std::optional<Schema> SchemaCreator::loadSchema(SchemaNode node, Library &library)
+Schema* SchemaCreator::loadSchema(SchemaNode node, Library &library)
 {
-    Schema schema;
+    Schema *schema = new Schema();
 
     for(auto &instance: node.instances) {
         if(library.hasComponent(instance.component.value)) {
-            schema.instances.push_back(loadComponentInstance(instance, library));
+            schema->instances.push_back(loadComponentInstance(instance, library));
         }
         if(library.hasBus(instance.component.value)) {
-            schema.instances.push_back(loadBusInstance(instance, library));
+            schema->instances.push_back(loadBusInstance(instance, library));
         }
     }
 
     for(auto &wire: node.wires) {
         auto w = loadWireInstance(wire);
         if(w) {
-            schema.wires.push_back(*w);
+            schema->wires.push_back(*w);
         }
     }
 
     for(auto &conn: node.connections) {
-        auto firstComponent = dynamic_cast<ComponentInstance*>(schema.getInstance(conn.first.instance.value));
+        auto firstComponent = dynamic_cast<ComponentInstance*>(schema->getInstance(conn.first.instance.value));
         if(firstComponent == NULL) {
             errors.push_back(SourceError{conn.first.instance.span, "unknown component"});
             continue;
@@ -762,7 +762,7 @@ std::optional<Schema> SchemaCreator::loadSchema(SchemaNode node, Library &librar
 
         ComponentInstance *secondComponent = NULL;
         if(conn.second.has_value()) {
-            secondComponent = dynamic_cast<ComponentInstance*>(schema.getInstance(conn.second->instance.value));
+            secondComponent = dynamic_cast<ComponentInstance*>(schema->getInstance(conn.second->instance.value));
             if(secondComponent == NULL) {
                 errors.push_back(SourceError{conn.second->instance.span, "unknown component"});
                 continue;
@@ -773,7 +773,7 @@ std::optional<Schema> SchemaCreator::loadSchema(SchemaNode node, Library &librar
             }
         }
 
-        auto bus = dynamic_cast<BusInstance*>(schema.getInstance(conn.bus.value));
+        auto bus = dynamic_cast<BusInstance*>(schema->getInstance(conn.bus.value));
         if(bus == NULL) {
             errors.push_back(SourceError{conn.bus.span, "unknown bus"});
             continue;
@@ -808,12 +808,12 @@ std::optional<Schema> SchemaCreator::loadSchema(SchemaNode node, Library &librar
             errors.push_back(SourceError{conn.span, "missing @wire"});
             continue;
         }
-        if(!schema.hasWire(conn.wire->value)) {
+        if(!schema->hasWire(conn.wire->value)) {
             errors.push_back(SourceError{conn.wire->span, "unknown wire"});
             continue;
         }
 
-        auto wire = schema.getWire(conn.wire->value);
+        auto wire = schema->getWire(conn.wire->value);
 
         std::vector<InstanceAttribute*> attributes;
         for(auto& attr: conn.attributes) {
@@ -837,9 +837,9 @@ std::optional<Schema> SchemaCreator::loadSchema(SchemaNode node, Library &librar
         }
 
         if(secondComponent == NULL) {
-            schema.connections.push_back(new BusConnectionInstance(firstComponent, attributes, bus, wire, *connection));
+            schema->connections.push_back(new BusConnectionInstance(firstComponent, attributes, bus, wire, *connection));
         } else {
-            schema.connections.push_back(new DirectConnectionInstance(firstComponent, secondComponent, attributes, bus, wire, *connection));
+            schema->connections.push_back(new DirectConnectionInstance(firstComponent, secondComponent, attributes, bus, wire, *connection));
         }
     }
 
diff --git a/comdel/domain/schemacreator.h b/comdel/domain/schemacreator.h
index 7766d1b..fca225c 100644
--- a/comdel/domain/schemacreator.h
+++ b/comdel/domain/schemacreator.h
@@ -138,7 +138,7 @@ public:
 
     std::optional<Library> loadLibrary(LibraryNode node);
 
-    std::optional<Schema> loadSchema(SchemaNode node, Library &library);
+    Schema* loadSchema(SchemaNode node, Library &library);
 };
 
 } // namespace domain
diff --git a/mainwindow.cpp b/mainwindow.cpp
index b6bb74b..94e3bc3 100644
--- a/mainwindow.cpp
+++ b/mainwindow.cpp
@@ -84,7 +84,7 @@ void MainWindow::onLoadLibrary() {
                 libraryDisplay->setLibrary(library);
 
                 // on library load we create a new schema
-                schema = domain::Schema();
+                schema = new domain::Schema();
                 schemaDisplay->setSchema(schema);
             }
 
@@ -137,7 +137,7 @@ void MainWindow::onLoadSchema() {
 }
 
 void MainWindow::onValidateSchema(bool /*toggled*/) {
-    if(!schema.has_value()) {
+    if(schema == nullptr) {
         return;
     }
 
@@ -191,7 +191,7 @@ void MainWindow::onValidateSchema(bool /*toggled*/) {
 
 void MainWindow::clear() {
     validationErrors.clear();
-    schema = std::nullopt;
+    schema = nullptr;
     library = std::nullopt;
 
     libraryDisplay->setLibrary(library);
diff --git a/mainwindow.h b/mainwindow.h
index bb89262..82aa1f6 100644
--- a/mainwindow.h
+++ b/mainwindow.h
@@ -28,7 +28,7 @@ public:
     display::Schema *schemaDisplay;
 
     std::optional<domain::Library> library = std::nullopt;
-    std::optional<domain::Schema> schema = std::nullopt;
+    domain::Schema* schema = nullptr;
 
     std::vector<domain::FunctionSignature> signatures;