diff --git a/.gitignore b/.gitignore
index 16242e2a62..27ded1a9d1 100644
--- a/.gitignore
+++ b/.gitignore
@@ -61,6 +61,7 @@ app/gui/qt/moc_mainwindow.cpp
 app/gui/qt/moc_sonicpiudpserver.cpp
 app/gui/qt/qrc_SonicPi.cpp
 app/gui/qt/utils/ruby_help.h
+app/gui/qt/utils/lang_list.h
 app/gui/qt/help/*.html
 app/gui/qt/help_files.qrc
 app/gui/qt/lang/*.qm
diff --git a/app/gui/qt/CMakeLists.txt b/app/gui/qt/CMakeLists.txt
index b4394a0076..32c818f98f 100644
--- a/app/gui/qt/CMakeLists.txt
+++ b/app/gui/qt/CMakeLists.txt
@@ -74,12 +74,15 @@ set(QT_SOURCES
 set(SOURCES
     ${QTAPP_ROOT}/main.cpp
     ${QTAPP_ROOT}/utils/scintilla_api.cpp
+    ${QTAPP_ROOT}/utils/sonicpi_i18n.cpp
     ${QTAPP_ROOT}/widgets/sonicpilog.cpp
     ${QTAPP_ROOT}/widgets/sonicpilog.h
     ${QTAPP_ROOT}/widgets/sonicpicontext.cpp
     ${QTAPP_ROOT}/widgets/sonicpicontext.h
     ${QTAPP_ROOT}/utils/scintilla_api.h
+    ${QTAPP_ROOT}/utils/sonicpi_i18n.h
     ${QTAPP_ROOT}/utils/ruby_help.h
+    ${QTAPP_ROOT}/utils/lang_list.h
     ${QTAPP_ROOT}/model/settings.h
     )
 
diff --git a/app/gui/qt/main.cpp b/app/gui/qt/main.cpp
index 35d6522fd4..660de9a750 100644
--- a/app/gui/qt/main.cpp
+++ b/app/gui/qt/main.cpp
@@ -11,12 +11,13 @@
 // notice is included.
 //++
 
+#include <iostream>
+
 #include <QApplication>
 #include <QSplashScreen>
 #include <QPixmap>
 #include <QBitmap>
 #include <QLabel>
-#include <QTranslator>
 #include <QLibraryInfo>
 
 #include "mainwindow.h"
@@ -35,7 +36,7 @@
 
 int main(int argc, char *argv[])
 {
-
+  std::cout << "Starting Sonic Pi..." << std::endl;
 #ifndef Q_OS_MAC
   Q_INIT_RESOURCE(SonicPi);
 #endif
@@ -49,16 +50,6 @@ int main(int argc, char *argv[])
 
   qRegisterMetaType<SonicPiLog::MultiMessage>("SonicPiLog::MultiMessage");
 
-  QString systemLocale = QLocale::system().uiLanguages()[0].replace("-", "_");
-
-  QTranslator qtTranslator;
-  qtTranslator.load("qt_" + systemLocale, QLibraryInfo::location(QLibraryInfo::TranslationsPath));
-  app.installTranslator(&qtTranslator);
-
-  QTranslator translator;
-  bool i18n = translator.load(QLatin1String("sonic-pi_") + systemLocale, QLatin1String(":/lang")) ||  systemLocale.startsWith("en") || systemLocale == "C";
-  app.installTranslator(&translator);
-
   app.setApplicationName(QObject::tr("Sonic Pi"));
   app.setStyle("gtk");
 
@@ -75,7 +66,7 @@ int main(int argc, char *argv[])
   splash->show();
   splash->repaint();
   app.processEvents();
-  MainWindow mainWin(app, i18n, splash);
+  MainWindow mainWin(app, splash);
 
   return app.exec();
 #elif _WIN32
@@ -109,7 +100,7 @@ int main(int argc, char *argv[])
   splash->show();
   splash->repaint();
   app.processEvents();
-  MainWindow mainWin(app, i18n, splash);
+  MainWindow mainWin(app, splash);
 
   // Fix for full screen mode. See: https://doc.qt.io/qt-5/windows-issues.html#fullscreen-opengl-based-windows
   QWindowsWindowFunctions::setHasBorderInFullScreen(mainWin.windowHandle(), true);
@@ -139,9 +130,8 @@ int main(int argc, char *argv[])
   splashWindow->show();
   app.processEvents();
 
-  MainWindow mainWin(app, i18n, splashWindow);
+  MainWindow mainWin(app, splashWindow);
   return app.exec();
 
 #endif
-
 }
diff --git a/app/gui/qt/mainwindow.cpp b/app/gui/qt/mainwindow.cpp
index 855cb6e14b..f71cf1b94e 100644
--- a/app/gui/qt/mainwindow.cpp
+++ b/app/gui/qt/mainwindow.cpp
@@ -52,6 +52,8 @@
 #include "widgets/sonicpilexer.h"
 #include "widgets/sonicpiscintilla.h"
 
+#include "utils/sonicpi_i18n.h"
+
 #include "utils/borderlesslinksproxystyle.h"
 #include "visualizer/scope_window.h"
 
@@ -89,9 +91,9 @@ using namespace std::chrono;
 using namespace SonicPi;
 
 #ifdef Q_OS_MAC
-MainWindow::MainWindow(QApplication& app, bool i18n, QMainWindow* splash)
+MainWindow::MainWindow(QApplication& app, QMainWindow* splash)
 #else
-MainWindow::MainWindow(QApplication& app, bool i18n, QSplashScreen* splash)
+MainWindow::MainWindow(QApplication& app, QSplashScreen* splash)
 #endif
 {
     app.installEventFilter(this);
@@ -103,7 +105,6 @@ MainWindow::MainWindow(QApplication& app, bool i18n, QSplashScreen* splash)
     this->piSettings = new SonicPiSettings();
 
     this->splash = splash;
-    this->i18n = i18n;
 
     // API and Client
     m_spClient = std::make_shared<QtAPIClient>(this);
@@ -126,7 +127,6 @@ MainWindow::MainWindow(QApplication& app, bool i18n, QSplashScreen* splash)
     version_num = 0;
     latest_version_num = 0;
     this->splash = splash;
-    this->i18n = i18n;
     QString settings_path = sonicPiConfigPath() + QDir::separator() + "gui-settings.ini";
 
     gui_settings = new QSettings(settings_path, QSettings::IniFormat);
@@ -139,6 +139,19 @@ MainWindow::MainWindow(QApplication& app, bool i18n, QSplashScreen* splash)
     m_spAPI->Init(rootPath().toStdString());
     guiID = QString::fromStdString(m_spAPI->GetGuid());
 
+    this->sonicPii18n = new SonicPii18n(rootPath());
+    std::cout << "[GUI] - Language setting: " << piSettings->language.toUtf8().constData() << std::endl;
+    std::cout << "[GUI] - System language: " << QLocale::system().name().toStdString() << std::endl;
+    this->ui_language = sonicPii18n->determineUILanguage(piSettings->language);
+    std::cout << "[GUI] - Using language: " << ui_language.toUtf8().constData() << std::endl;
+    this->i18n = sonicPii18n->loadTranslations(ui_language);
+
+    if(i18n) {
+      std::cout << "[GUI] - translations available " << std::endl;
+    } else {
+      std::cout << "[GUI] - translations unavailable (using EN)" << std::endl;
+    }
+
     std::cout << "[GUI] - hiding main window" << std::endl;
     hide();
 
@@ -212,6 +225,11 @@ MainWindow::MainWindow(QApplication& app, bool i18n, QSplashScreen* splash)
     toggleOSCServer(1);
 
     app.setActiveWindow(tabs->currentWidget());
+
+    if (!i18n) {
+      showLanguageLoadingError();
+    }
+
     showWelcomeScreen();
 }
 
@@ -348,7 +366,8 @@ void MainWindow::setupWindowStructure()
     prefsWidget->setAllowedAreas(Qt::RightDockWidgetArea);
     prefsWidget->setFeatures(QDockWidget::DockWidgetClosable);
 
-    settingsWidget = new SettingsWidget(m_spAPI->GetPort(SonicPiPortId::server_osc_cues), piSettings, this);
+    settingsWidget = new SettingsWidget(m_spAPI->GetPort(SonicPiPortId::server_osc_cues), i18n, piSettings, sonicPii18n, this);
+    connect(settingsWidget, SIGNAL(restartApp()), this, SLOT(restartApp()));
     connect(settingsWidget, SIGNAL(volumeChanged(int)), this, SLOT(changeSystemPreAmp(int)));
     connect(settingsWidget, SIGNAL(mixerSettingsChanged()), this, SLOT(mixerSettingsChanged()));
     connect(settingsWidget, SIGNAL(midiSettingsChanged()), this, SLOT(toggleMidi()));
@@ -1216,6 +1235,18 @@ void MainWindow::startupError(QString msg)
 // TODO: Add format error to API
 }
 
+void MainWindow::showLanguageLoadingError() {
+  QMessageBox msgBox(this);
+  msgBox.setIcon(QMessageBox::Warning);
+  msgBox.setText(QString(tr("Failed to load translations for language: %1")).arg(sonicPii18n->getNativeLanguageName(this->ui_language)));
+  msgBox.setInformativeText(tr("Falling back to English. Sorry about this.") + "\n" + tr("Please consider reporting a bug at") + "\nhttp://github.com/sonic-pi-net/sonic-pi/issues");
+
+  QPushButton *okButton = msgBox.addButton(tr("OK"), QMessageBox::AcceptRole);
+  msgBox.setDefaultButton(okButton);
+
+  msgBox.exec();
+}
+
 void MainWindow::replaceBuffer(QString id, QString content, int line, int index, int first_line)
 {
     SonicPiScintilla* ws = filenameToWorkspace(id.toStdString());
@@ -2880,6 +2911,39 @@ void MainWindow::createToolBar()
     viewMenu->addAction(focusHelpListingAct);
     viewMenu->addAction(focusHelpDetailsAct);
     viewMenu->addAction(focusErrorsAct);
+
+    languageMenu = menuBar()->addMenu(tr("Language"));
+    QStringList available_languages = sonicPii18n->getAvailableLanguages();
+
+    langActionGroup = new QActionGroup(this);
+    langActionGroup->setExclusionPolicy(QActionGroup::ExclusionPolicy::Exclusive);
+
+    QSignalMapper *signalMapper = new QSignalMapper(this);
+
+    for (size_t i = 0; i < available_languages.length(); i += 1) {
+      bool is_current_lang = (available_languages[i] == piSettings->language);
+
+      QAction *langAct = new QAction(sonicPii18n->getNativeLanguageName(available_languages[i]), this);
+      langAct->setCheckable(true);
+      langAct->setChecked(is_current_lang);
+
+      connect(langAct, SIGNAL(triggered()), signalMapper, SLOT(map()));
+      signalMapper->setMapping(langAct, i);
+
+      langActionGroup->addAction(langAct);
+      languageMenu->addAction(langAct);
+
+      if (i == 0) { // add separator after System language
+        languageMenu->addSeparator();
+      }
+    }
+
+    connect(signalMapper, SIGNAL(mappedInt(int)), settingsWidget, SLOT(updateUILanguage(int)));
+    connect(settingsWidget, SIGNAL(uiLanguageChanged(QString)), this, SLOT(updateSelectedUILanguageAction(QString)));
+}
+
+void MainWindow::updateSelectedUILanguageAction(QString lang) {
+  langActionGroup->actions()[sonicPii18n->getAvailableLanguages().indexOf(lang)]->setChecked(true);
 }
 
 QString MainWindow::readFile(QString name)
@@ -3074,6 +3138,7 @@ void MainWindow::readSettings()
     std::cout << "[GUI] - reading settings" << std::endl;
 
     // Read in preferences from previous session
+    piSettings->language = gui_settings->value("prefs/language", "system_language").toString();
     piSettings->show_buttons = gui_settings->value("prefs/show-buttons", true).toBool();
     piSettings->show_tabs = gui_settings->value("prefs/show-tabs", true).toBool();
     piSettings->show_log = gui_settings->value("prefs/show-log", true).toBool();
@@ -3100,6 +3165,7 @@ void MainWindow::readSettings()
     piSettings->show_scope_labels = gui_settings->value("prefs/scope/show-labels", false).toBool();
     piSettings->show_cues = gui_settings->value("prefs/show_cues", true).toBool();
     QString styleName = gui_settings->value("prefs/theme", "").toString();
+
     piSettings->themeStyle = theme->themeNameToStyle(styleName);
     piSettings->show_autocompletion = gui_settings->value("prefs/show-autocompletion", true).toBool();
     piSettings->show_context = gui_settings->value("prefs/show-context", true).toBool();
@@ -3121,10 +3187,13 @@ void MainWindow::restoreScopeState(std::vector<QString> names)
 void MainWindow::writeSettings()
 {
     std::cout << "[GUI] - writing settings" << std::endl;
+
     gui_settings->setValue("pos", pos());
     gui_settings->setValue("size", size());
     gui_settings->setValue("first_time", 0);
 
+    gui_settings->setValue("prefs/language", piSettings->language);
+
     gui_settings->setValue("prefs/midi-default-channel", piSettings->midi_default_channel);
     gui_settings->setValue("prefs/midi-enable", piSettings->midi_enabled);
     gui_settings->setValue("prefs/osc-public", piSettings->osc_public);
@@ -3172,6 +3241,9 @@ void MainWindow::writeSettings()
     gui_settings->setValue("docsplitState", docsplit->saveState());
     gui_settings->setValue("windowState", saveState());
     gui_settings->setValue("windowGeom", saveGeometry());
+
+    // Force Qt to write the settings to the ini file
+    gui_settings->sync();
 }
 
 void MainWindow::loadFile(const QString& fileName, SonicPiScintilla*& text)
@@ -3261,6 +3333,31 @@ void MainWindow::onExitCleanup()
     }
 }
 
+void MainWindow::restartApp() {
+    QApplication* app = dynamic_cast<QApplication*>(parent());
+    statusBar()->showMessage(tr("Restarting Sonic Pi..."), 10000);
+
+    // Save settings and perform some cleanup
+    writeSettings();
+    onExitCleanup();
+    std::cout << "Performing application restart..." << std::endl;
+
+    // Create new process
+    QStringList args = qApp->arguments();
+    args.removeFirst();
+    QProcess process;
+    bool restart_success = process.startDetached(qApp->arguments()[0], args);
+    if (restart_success) {
+      std::cout << "Successfully restarted sonic-pi" << std::endl;
+    } else {
+      std::cout << "Failed to restart sonic-pi" << std::endl;
+    }
+
+    // Quit
+    app->exit(0);
+    exit(0);
+}
+
 void MainWindow::heartbeatOSC()
 {
     // Message msg("/gui-heartbeat");
diff --git a/app/gui/qt/mainwindow.h b/app/gui/qt/mainwindow.h
index e1d330cb74..316b170879 100644
--- a/app/gui/qt/mainwindow.h
+++ b/app/gui/qt/mainwindow.h
@@ -17,6 +17,7 @@
 #include <vector>
 #include <memory>
 
+
 #include <QDate>
 #include <QMainWindow>
 #include <QFuture>
@@ -34,6 +35,7 @@
 #include "config.h"
 
 class QAction;
+class QActionGroup;
 class QMenu;
 class QToolBar;
 class QLineEdit;
@@ -67,6 +69,7 @@ class InfoWidget;
 class SettingsWidget;
 class Scope;
 class ScintillaAPI;
+class SonicPii18n;
 class SonicPiLog;
 class SonicPiScintilla;
 class SonicPiTheme;
@@ -91,9 +94,9 @@ class MainWindow : public QMainWindow
 
     public:
 #if defined(Q_OS_MAC)
-        MainWindow(QApplication &ref, bool i18n, QMainWindow* splash);
+        MainWindow(QApplication &ref, QMainWindow* splash);
 #else
-        MainWindow(QApplication &ref, bool i18n, QSplashScreen* splash);
+        MainWindow(QApplication &ref, QSplashScreen* splash);
 #endif
 
         SonicPiLog* GetOutputPane() const;
@@ -118,6 +121,8 @@ class MainWindow : public QMainWindow
 
         bool loaded_workspaces;
         QString hash_salt;
+        QString ui_language;
+
 
     protected:
         void closeEvent(QCloseEvent *event);
@@ -132,6 +137,7 @@ class MainWindow : public QMainWindow
 
        private slots:
 
+        void updateSelectedUILanguageAction(QString lang);
         void updateContext(int line, int index);
         void updateContextWithCurrentWs();
         void docLinkClicked(const QUrl &url);
@@ -178,6 +184,7 @@ class MainWindow : public QMainWindow
         void help();
         void toggleHelpIcon();
         void onExitCleanup();
+        void restartApp();
         void toggleRecording();
         void toggleRecordingOnIcon();
         void changeSystemPreAmp(int val, int silent=0);
@@ -229,6 +236,7 @@ class MainWindow : public QMainWindow
         void splashClose();
         void setMessageBoxStyle();
         void startupError(QString msg);
+        void showLanguageLoadingError();
         void tabNext();
         void tabPrev();
         void tabGoto(int index);
@@ -327,11 +335,13 @@ class MainWindow : public QMainWindow
         QString rootPath();
 
         void addUniversalCopyShortcuts(QTextEdit *te);
+        void updateTranslatedUIText();
 
-  QMenu *liveMenu, *codeMenu, *audioMenu, *displayMenu, *viewMenu, *ioMenu, *ioMidiInMenu, *ioMidiOutMenu, *ioMidiOutChannelMenu, *localIpAddressesMenu, *themeMenu, *scopeKindVisibilityMenu;
+  QMenu *liveMenu, *codeMenu, *audioMenu, *displayMenu, *viewMenu, *ioMenu, *ioMidiInMenu, *ioMidiOutMenu, *ioMidiOutChannelMenu, *localIpAddressesMenu, *themeMenu, *scopeKindVisibilityMenu, *languageMenu;
 
         QSettings *gui_settings;
         SonicPiSettings *piSettings;
+        SonicPii18n *sonicPii18n;
 
         bool focusMode;
         QCheckBox *startup_error_reported;
@@ -380,6 +390,7 @@ class MainWindow : public QMainWindow
 
   QAction *exitAct, *runAct, *stopAct, *saveAsAct, *loadFileAct, *recAct, *textAlignAct, *textIncAct, *textDecAct, *scopeAct, *infoAct, *helpAct, *prefsAct, *focusEditorAct, *focusLogsAct, *focusContextAct, *focusCuesAct, *focusPreferencesAct, *focusHelpListingAct, *focusHelpDetailsAct, *focusErrorsAct, *showLineNumbersAct, *showAutoCompletionAct, *showContextAct, *audioSafeAct, *audioTimingGuaranteesAct, *enableExternalSynthsAct, *mixerInvertStereoAct, *mixerForceMonoAct, *midiEnabledAct, *enableOSCServerAct, *allowRemoteOSCAct, *showLogAct, *showCuesAct, *logAutoScrollAct, *logCuesAct, *logSynthsAct, *clearOutputOnRunAct, *autoIndentOnRunAct, *showButtonsAct, *showTabsAct, *fullScreenAct, *lightThemeAct, *darkThemeAct, *proLightThemeAct, *proDarkThemeAct, *highContrastThemeAct, *showScopeLabelsAct;
   QShortcut *runSc, *stopSc, *saveAsSc, *loadFileSc, *recSc, *textAlignSc, *textIncSc, *textDecSc, *scopeSc, *infoSc, *helpSc, *prefsSc, *focusEditorSc, *focusLogsSc, *focusContextSc, *focusCuesSc, *focusPreferencesSc, *focusHelpListingSc, *focusHelpDetailsSc, *focusErrorsSc;
+        QActionGroup *langActionGroup;
 
         SettingsWidget *settingsWidget;
 
diff --git a/app/gui/qt/model/settings.h b/app/gui/qt/model/settings.h
index 757da5134f..57f1e28df9 100644
--- a/app/gui/qt/model/settings.h
+++ b/app/gui/qt/model/settings.h
@@ -24,6 +24,7 @@ class SonicPiSettings {
     QString midi_default_channel_str;
 
     // EditorSettings
+    QString language;
     bool auto_indent_on_run;
     bool show_line_numbers;
     bool show_log;
diff --git a/app/gui/qt/theme/app.qss b/app/gui/qt/theme/app.qss
index 9edc265cdc..aa70a384d6 100644
--- a/app/gui/qt/theme/app.qss
+++ b/app/gui/qt/theme/app.qss
@@ -535,3 +535,8 @@ QPushButton::pressed
     background-color: pressedButtonColor;
     color: pressedButtonTextColor;
 }
+
+QMessageBox
+{
+    background: windowColor;
+}
diff --git a/app/gui/qt/utils/lang_list.tmpl b/app/gui/qt/utils/lang_list.tmpl
new file mode 100644
index 0000000000..c8f0703033
--- /dev/null
+++ b/app/gui/qt/utils/lang_list.tmpl
@@ -0,0 +1,16 @@
+//--
+// This file is part of Sonic Pi: http://sonic-pi.net
+// Full project source: https://github.com/samaaron/sonic-pi
+// License: https://github.com/samaaron/sonic-pi/blob/main/LICENSE.md
+//
+// Copyright 2020 by Sam Aaron (http://sam.aaron.name).
+// All rights reserved.
+//
+// Permission is granted for use, copying, modification, distribution,
+// and distribution of modified versions of this work as long as this
+// notice is included.
+//++
+
+// AUTO-GENERATED-DOCS
+// Do not manually add any code below this comment
+// otherwise it may be removed
diff --git a/app/gui/qt/utils/sonicpi_i18n.cpp b/app/gui/qt/utils/sonicpi_i18n.cpp
new file mode 100644
index 0000000000..8f10fcb321
--- /dev/null
+++ b/app/gui/qt/utils/sonicpi_i18n.cpp
@@ -0,0 +1,207 @@
+#include <QDir>
+#include <QString>
+#include <QStringList>
+#include <QLocale>
+#include <QTranslator>
+#include <QApplication>
+#include <QLibraryInfo>
+
+#include <iostream>
+
+#include "sonicpi_i18n.h"
+#include "lang_list.h"
+
+SonicPii18n::SonicPii18n(QString rootpath) {
+  this->root_path = rootpath;
+  this->system_languages = findSystemLanguages();
+  this->system_language_available = true; // Set to true unless we can't load the system language
+  this->available_languages = findAvailableLanguages();
+  this->currently_loaded_language = "en";
+
+  //checkAllTranslations(); // For testing and debugging purposes
+}
+
+SonicPii18n::~SonicPii18n() {
+}
+
+QString SonicPii18n::determineUILanguage(QString lang_pref) {
+  QStringList available_languages = getAvailableLanguages();
+  //std::cout << available_languages.join("\n").toUtf8().constData() << std::endl;
+  QLocale locale;
+
+  if (lang_pref != "system_language") {
+    if (available_languages.contains(lang_pref)) {
+        return lang_pref;
+    }
+
+    // Add the general language as a fallback (e.g. pt_BR -> pt)
+    QString general_name = lang_pref;
+    general_name.truncate(lang_pref.lastIndexOf('_'));
+    general_name.truncate(general_name.lastIndexOf('-'));
+
+    if (available_languages.contains(general_name)) {
+        return general_name;
+    }
+  } else {
+    QStringList preferred_languages = locale.uiLanguages();
+    // If the setting is set to system_language...
+      // ...run through the list of preferred languages
+    std::cout << "[GUI] [i18n] - Looping through preferred ui languages" << std::endl;
+
+    QString l;
+    for (int i = 0; i < preferred_languages.length(); i += 1) {
+      l = preferred_languages[i];
+      l.replace("-", "_");
+
+      //std::cout << preferred_languages[i].toUtf8().constData() << std::endl;
+      if (available_languages.contains(l)) {
+          return l;
+      }
+    }
+  }
+
+  // Fallback to English
+  this->system_language_available = false;
+  return "en";
+}
+
+QStringList SonicPii18n::findSystemLanguages() {
+  QLocale locale;
+  QStringList preferred_languages = locale.uiLanguages();
+  std::cout << "[GUI] [i18n] - Looping through preferred ui languages" << std::endl;
+  for (int i = 0; i < preferred_languages.length(); i += 1) {
+    preferred_languages[i] = preferred_languages[i].replace("-", "_");
+  }
+  return preferred_languages;
+}
+
+QStringList SonicPii18n::findAvailableLanguages() {
+  QStringList languages;
+
+  QString m_langPath = root_path + "/app/gui/qt/lang";
+  //std::cout << m_langPath.toUtf8().constData() << std::endl;
+  QDir dir(m_langPath);
+  QStringList fileNames = dir.entryList(QStringList("sonic-pi_*.qm"));
+
+  for (int i = 0; i < fileNames.size(); ++i) {
+    // extract the language from the filename
+    QString lang;
+    lang = fileNames[i]; // "sonic-pi_pt_BR.qm"
+    lang.truncate(lang.lastIndexOf('.')); // "sonic-pi_pt_BR"
+    lang.remove(0, lang.lastIndexOf("sonic-pi_") + 9); // "pt_BR"
+    //lang.replace("_", "-"); // Replace underscores with dashes so it matches the language codes e.g: "pt-BR"
+    //std::cout << lang.toUtf8().constData() << '\n';
+    languages << lang;
+  }
+  // Add the source language
+  languages << "en_GB";
+  languages.sort();
+  return languages;
+}
+
+bool SonicPii18n::loadTranslations(QString lang) {
+  QString language = lang;
+  bool i18n = false;
+  QCoreApplication* app = QCoreApplication::instance();
+
+  // Remove any previous translations
+  app->removeTranslator(&translator);
+  app->removeTranslator(&qtTranslator);
+
+  std::cout << "[GUI] [i18n] - Loading translations for " << language.toUtf8().constData() << std::endl;
+
+  i18n = translator.load("sonic-pi_" + language, ":/lang/") || language == "en_GB" || language == "en" || language == "C";
+  if (!i18n) {
+    std::cout << "[GUI] [i18n] - Error: Failed to load language translation for " << language.toUtf8().constData() << std::endl;
+    language = "en_GB";
+  }
+  app->installTranslator(&translator);
+
+  qtTranslator.load("qt_" + language, QLibraryInfo::location(QLibraryInfo::TranslationsPath));
+  app->installTranslator(&qtTranslator);
+
+  this->currently_loaded_language = language;
+
+  return i18n;
+}
+
+QStringList SonicPii18n::getAvailableLanguages() {
+  QStringList list = this->available_languages;
+  list.prepend("system_language");
+  return list;
+}
+
+QStringList SonicPii18n::getSystemLanguages() {
+  return system_languages;
+};
+
+bool SonicPii18n::isSystemLanguageAvailable() {
+  return system_language_available;
+};
+
+QString SonicPii18n::currentlyLoadedLanguage() {
+  return currently_loaded_language;
+};
+
+QString SonicPii18n::getNativeLanguageName(QString lang) {
+  if (lang == "system_language") {
+    return tr("System language");
+  }
+
+  std::map<QString, QString>::iterator it = native_language_names.find(lang);
+  if(it != native_language_names.end()) {
+    // language found
+    return native_language_names[lang];
+  } else {
+    std::cout << "[GUI] [i18n] - Warning: Predefined language name not found: '" << lang.toUtf8().constData() << "'" << std::endl;
+    // Try using QLocale to find the native language name
+    QLocale locale(lang);
+    QString name = locale.nativeLanguageName();
+    if (name != "C" && name != "") {
+      return locale.nativeLanguageName();
+    } else {
+      std::cout << "[GUI] [i18n] - Warning: Invalid language code: '" << lang.toUtf8().constData() << "'" << std::endl;
+      return lang;
+    }
+  }
+}
+
+QStringList SonicPii18n::getNativeLanguageNames(QStringList languages) {
+  QStringList language_names;
+  for (size_t i = 0; i < languages.length(); i += 1) {
+    language_names << getNativeLanguageName(languages[i]);
+  }
+  return language_names;
+}
+
+// For testing and debugging purposes
+bool SonicPii18n::checkAllTranslations() {
+  QStringList failed_to_load = QStringList();
+  bool all_succeeded = true;
+
+  std::cout << "==========================================" << std::endl;
+  std::cout << "Testing all found language translations..." << std::endl;
+  for (int i = 0; i < this->available_languages.size(); ++i) {
+    QString lang = this->available_languages[i];
+    bool success = loadTranslations(lang);
+    if (success) {
+      std::cout << lang.toUtf8().constData() << ": ✓" << std::endl;
+    } else {
+      std::cout << lang.toUtf8().constData() << ": ✗" << std::endl;
+      failed_to_load << lang;
+      all_succeeded = false;
+    }
+  }
+  std::cout << "Done" << std::endl;
+
+  std::cout << "------------------------------------------" << std::endl;
+  if (failed_to_load.length() > 0) {
+    std::cout << "Some translations failed to load:" << std::endl;
+    std::cout << failed_to_load.join("\n").toUtf8().constData() << std::endl;
+  } else {
+    std::cout << "All found translations loaded successfully :)" << std::endl;
+  }
+  std::cout << "==========================================" << std::endl;
+
+  return all_succeeded;
+}
diff --git a/app/gui/qt/utils/sonicpi_i18n.h b/app/gui/qt/utils/sonicpi_i18n.h
new file mode 100644
index 0000000000..a12949a998
--- /dev/null
+++ b/app/gui/qt/utils/sonicpi_i18n.h
@@ -0,0 +1,56 @@
+//--
+// This file is part of Sonic Pi: http://sonic-pi.net
+// Full project source: https://github.com/samaaron/sonic-pi
+// License: https://github.com/samaaron/sonic-pi/blob/main/LICENSE.md
+//
+// Copyright 2013, 2014, 2015, 2016 by Sam Aaron (http://sam.aaron.name).
+// All rights reserved.
+//
+// Permission is granted for use, copying, modification, and
+// distribution of modified versions of this work as long as this
+// notice is included.
+//++
+
+#include <QObject>
+#include <map>
+
+#ifndef SONICPI_I18N_H
+#define SONICPI_I18N_H
+
+class SonicPii18n : public QObject {
+public:
+  SonicPii18n(QString rootpath);
+  ~SonicPii18n();
+
+
+public slots:
+  QString determineUILanguage(QString lang_pref);
+  bool loadTranslations(QString lang);
+
+  QStringList getAvailableLanguages();
+  QStringList getSystemLanguages();
+  bool isSystemLanguageAvailable();
+  QString currentlyLoadedLanguage();
+
+  QString getNativeLanguageName(QString lang);
+  QStringList getNativeLanguageNames(QStringList languages);
+
+
+private:
+  QString root_path;
+
+  QTranslator qtTranslator;
+  QTranslator translator;
+
+  QStringList available_languages;
+  QStringList system_languages;
+  bool system_language_available;
+  QString currently_loaded_language;
+
+  static std::map<QString, QString> native_language_names;
+
+  QStringList findAvailableLanguages();
+  QStringList findSystemLanguages();
+  bool checkAllTranslations();
+};
+#endif
diff --git a/app/gui/qt/widgets/settingswidget.cpp b/app/gui/qt/widgets/settingswidget.cpp
index e124349131..66449cd059 100644
--- a/app/gui/qt/widgets/settingswidget.cpp
+++ b/app/gui/qt/widgets/settingswidget.cpp
@@ -1,4 +1,5 @@
 #include "settingswidget.h"
+#include "utils/sonicpi_i18n.h"
 
 #include <QSettings>
 #include <QVBoxLayout>
@@ -15,14 +16,19 @@
 #include <QPushButton>
 #include <QSignalMapper>
 #include <QVBoxLayout>
+#include <QMessageBox>
 #include <QSize>
 
 /**
  * Default Constructor
  */
-SettingsWidget::SettingsWidget( int port, SonicPiSettings *piSettings,  QWidget *parent) {
+SettingsWidget::SettingsWidget(int port, bool i18n, SonicPiSettings *piSettings, SonicPii18n *sonicPii18n, QWidget *parent) {
     this->piSettings = piSettings;
+    this->i18n = i18n;
+    this->sonicPii18n = sonicPii18n;
+    this->available_languages = sonicPii18n->getAvailableLanguages();
     server_osc_cues_port = port;
+
     prefTabs = new QTabWidget();
 
     QGridLayout *grid = new QGridLayout;
@@ -43,25 +49,31 @@ SettingsWidget::SettingsWidget( int port, SonicPiSettings *piSettings,  QWidget
     QGroupBox *update_prefs_box = createUpdatePrefsTab();
     prefTabs->addTab(update_prefs_box, tr("Updates"));
 
-    if (!i18n) {
-        QGroupBox *translation_box = new QGroupBox("Translation");
-        QVBoxLayout *translation_box_layout = new QVBoxLayout;
-        QLabel *go_translate = new QLabel;
-        go_translate->setOpenExternalLinks(true);
-        go_translate->setText(
-                "Sonic Pi hasn't been translated to " +
-                QLocale::languageToString(QLocale::system().language()) +
-                " yet.<br/>" +
-                "We rely on crowdsourcing to help create and maintain translations.<br/>" +
-                "<a href=\"https://github.com/samaaron/sonic-pi/blob/main/TRANSLATION.md\">" +
-                "Please consider helping to translate Sonic Pi to your language.</a> "
-                );
-        go_translate->setTextFormat(Qt::RichText);
-        translation_box_layout->addWidget(go_translate);
-        translation_box->setLayout(translation_box_layout);
-
-        grid->addWidget(translation_box, 3, 0, 1, 2);
+    QGroupBox *language_prefs_box = createLanguagePrefsTab();
+    prefTabs->addTab(language_prefs_box, tr("Language"));
+
+    if (piSettings->language == "system_language") {
+      if (!sonicPii18n->isSystemLanguageAvailable()) {
+          QGroupBox *translation_box = new QGroupBox("Translation");
+          QVBoxLayout *translation_box_layout = new QVBoxLayout;
+          QLabel *go_translate = new QLabel;
+          go_translate->setOpenExternalLinks(true);
+          go_translate->setText(
+                  "Sonic Pi hasn't been translated to " +
+                  QLocale::languageToString(QLocale::system().language()) +
+                  " yet.<br/>" +
+                  "We rely on crowdsourcing to help create and maintain translations.<br/>" +
+                  "<a href=\"https://github.com/sonic-pi-net/sonic-pi/blob/main/TRANSLATION.md\">" +
+                  "Please consider helping to translate Sonic Pi to your language.</a> "
+                  );
+          go_translate->setTextFormat(Qt::RichText);
+          translation_box_layout->addWidget(go_translate);
+          translation_box->setLayout(translation_box_layout);
+
+          grid->addWidget(translation_box, 3, 0, 1, 2);
+      }
     }
+
     settingsChanged();
     connectAll();
     setLayout(grid);
@@ -365,11 +377,14 @@ QGroupBox* SettingsWidget::createEditorPrefsTab() {
     debug_box_layout->addWidget(clear_output_on_run);
     debug_box->setLayout(debug_box_layout);
 
+
+
     gridEditorPrefs->addWidget(editor_display_box, 0, 0);
     gridEditorPrefs->addWidget(editor_look_feel_box, 0, 1);
     gridEditorPrefs->addWidget(automation_box, 1, 1);
     gridEditorPrefs->addWidget(debug_box, 1, 0);
 
+
     editor_box->setLayout(gridEditorPrefs);
     return editor_box;
 }
@@ -463,6 +478,45 @@ QGroupBox* SettingsWidget::createUpdatePrefsTab() {
     return update_prefs_box;
 }
 
+/**
+ * create Language Preferences Tab of Settings Widget
+ */
+QGroupBox* SettingsWidget::createLanguagePrefsTab() {
+    QGroupBox *language_box = new QGroupBox(tr("Language"));
+    language_box->setToolTip(tr("Configure language settings"));
+    QSizePolicy languagePrefSizePolicy(QSizePolicy::Minimum, QSizePolicy::Fixed);
+    language_box->setSizePolicy(languagePrefSizePolicy);
+
+    language_option_label = new QLabel;
+    language_option_label->setText(tr("UI & Tutorial Language (Requires a restart to take effect)"));
+    language_option_label->setToolTip(tr("Change the language of the UI & Tutorial (Requires a restart to take effect)"));
+
+    language_combo = new QComboBox();
+    add_language_combo_box_entries(language_combo);
+    language_combo->setToolTip(tr("Change the language of the UI & Tutorial"));
+    language_combo->setMinimumContentsLength(2);
+    language_combo->setSizeAdjustPolicy(QComboBox::AdjustToMinimumContentsLength);
+
+    language_details_label = new QLabel;
+
+    language_info_label = new QLabel;
+    language_info_label->setText(tr("Translations have been generously provided by volunteers \non https://hosted.weblate.org/projects/sonic-pi/. Thank you! :)"));
+
+    QVBoxLayout *language_box_layout = new QVBoxLayout;
+
+    language_box_layout->addWidget(language_option_label);
+    language_box_layout->addWidget(language_combo);
+    language_box_layout->addWidget(language_details_label);
+    language_box_layout->addWidget(language_info_label);
+
+    language_box->setLayout(language_box_layout);
+
+    QGroupBox *language_prefs_box = new QGroupBox();
+    QGridLayout *language_prefs_box_layout = new QGridLayout;
+    language_prefs_box_layout->addWidget(language_box, 0, 0, 0, 0);
+    language_prefs_box->setLayout(language_prefs_box_layout);
+    return language_prefs_box;
+}
 
 // TODO utils?
 QString SettingsWidget::tooltipStrShiftMeta(char key, QString str) {
@@ -490,7 +544,11 @@ void SettingsWidget::updateScopeKindVisibility() {
     QCheckBox *cb = qobject_cast<QCheckBox*>(scope_box_kinds_layout->itemAt(i)->widget());
     cb->setChecked(piSettings->isScopeActive(cb->text()));
   }
+}
 
+void SettingsWidget::updateSelectedUILanguage(QString lang) {
+  int index = available_languages.indexOf(lang);
+  language_combo->setCurrentIndex(index);
 }
 
 void SettingsWidget::toggleScope( QWidget* qw ) {
@@ -502,6 +560,71 @@ void SettingsWidget::toggleScope( QWidget* qw ) {
   emit scopeChanged(name);
 }
 
+// TODO: Implement real-time language switching
+void SettingsWidget::updateUILanguage(int index) {
+    QString lang = available_languages[index];
+    std::cout << "Changed language to " << lang.toUtf8().constData() << std::endl;
+    if (lang != piSettings->language) {
+        std::cout << "Current language:  " << piSettings->language.toUtf8().constData() << std::endl;
+        std::cout << "New language selected: " << lang.toUtf8().constData() << std::endl;
+        QString old_lang = sonicPii18n->getNativeLanguageName(piSettings->language);
+        QString new_lang = sonicPii18n->getNativeLanguageName(lang);
+
+        // Load new language
+        //QString language = sonicPii18n->determineUILanguage(lang);
+        //sonicPii18n->loadTranslations(language);
+        //QString title_new = tr("Updated the UI language from %s to %s").arg();
+
+        QMessageBox msgBox(this);
+        msgBox.setText(QString(tr("You've selected a new language: %1")).arg(new_lang));
+        QString info_text = (
+          tr("Do you want to apply this language?")
+          + "\n"
+          + tr("The new language will be applied when you next start Sonic Pi.")
+        );
+
+        if (lang == "system_language") {
+          info_text = tr("System languages found: %1").arg(sonicPii18n->getNativeLanguageNames(sonicPii18n->getSystemLanguages()).join(", ")) + "\n" + info_text;
+        }
+
+        msgBox.setInformativeText(info_text);
+        QPushButton *applyButton = msgBox.addButton(tr("Apply"), QMessageBox::ActionRole);
+        QPushButton *dismissButton = msgBox.addButton(tr("Cancel"), QMessageBox::RejectRole);
+        msgBox.setDefaultButton(applyButton);
+        msgBox.setIcon(QMessageBox::Question);
+        msgBox.exec();
+
+        if (msgBox.clickedButton() == (QAbstractButton*)applyButton) {
+          piSettings->language = lang;
+          updateSelectedUILanguage(piSettings->language);
+          emit uiLanguageChanged(piSettings->language);
+
+          language_details_label->setText(
+            tr("<b>The new language will be applied when you next start Sonic Pi.</b><br>")
+            + tr("Current UI language: %1\n").arg(sonicPii18n->getNativeLanguageName(sonicPii18n->currentlyLoadedLanguage()))
+          );
+
+          QMessageBox restartMsgBox(this);
+          restartMsgBox.setText(QString(tr("Restart Sonic Pi?")));
+          QString info_text = (tr("Do you want to restart Sonic Pi now? This will stop any current runs & recordings."));
+          QPushButton *restartButton = restartMsgBox.addButton(tr("Restart"), QMessageBox::ActionRole);
+          QPushButton *dismissButton = restartMsgBox.addButton(tr("Dismiss"), QMessageBox::RejectRole);
+          restartMsgBox.setInformativeText(info_text);
+          restartMsgBox.setDefaultButton(dismissButton);
+          restartMsgBox.setIcon(QMessageBox::Question);
+          restartMsgBox.exec();
+          if (restartMsgBox.clickedButton() == (QAbstractButton*)restartButton) {
+            emit restartApp();
+          }
+            //emit uiLanguageChanged(lang);
+        } else if (msgBox.clickedButton() == (QAbstractButton*)dismissButton) {
+            // Don't apply the new language settings
+            updateSelectedUILanguage(piSettings->language);
+            emit uiLanguageChanged(piSettings->language);
+        }
+
+    }
+}
 
 void SettingsWidget::update_mixer_invert_stereo() {
     emit mixerSettingsChanged();
@@ -629,7 +752,7 @@ void SettingsWidget::autoIndentOnRun() {
 }
 
 void SettingsWidget::openSonicPiNet() {
-  QDesktopServices::openUrl(QUrl("http://sonic-pi.net", QUrl::TolerantMode));
+  QDesktopServices::openUrl(QUrl("https://sonic-pi.net", QUrl::TolerantMode));
 }
 
 void SettingsWidget::updateVersionInfo( QString info_string, QString visit, bool sonic_pi_net_visible, bool check_now_visible) {
@@ -641,6 +764,7 @@ void SettingsWidget::updateVersionInfo( QString info_string, QString visit, bool
 
 void SettingsWidget::updateSettings() {
     std::cout << "[GUI] - Update Settings" << std::endl;
+    piSettings->language = available_languages[language_combo->currentIndex()];
     piSettings->mixer_invert_stereo = mixer_invert_stereo->isChecked();
     piSettings->mixer_force_mono = mixer_force_mono->isChecked();
     piSettings->check_args = check_args->isChecked();
@@ -681,6 +805,18 @@ void SettingsWidget::updateSettings() {
 }
 
 void SettingsWidget::settingsChanged() {
+    language_combo->setCurrentIndex(available_languages.indexOf(piSettings->language));
+    QString language_detail_text = "";
+    if (!i18n) {
+      language_detail_text += "<b>Failed to load language translation. Using English (UK).</b>";
+    }
+    if (piSettings->language == "system_language") {
+      language_detail_text += (
+        tr("System languages: %1\n").arg(sonicPii18n->getNativeLanguageNames(sonicPii18n->getSystemLanguages()).join(", "))
+        + tr("Current UI language: %1\n").arg(sonicPii18n->getNativeLanguageName(sonicPii18n->currentlyLoadedLanguage()))
+      );
+    }
+    language_details_label->setText(language_detail_text);
 
     mixer_invert_stereo->setChecked(piSettings->mixer_invert_stereo);
     mixer_force_mono->setChecked(piSettings->mixer_force_mono);
@@ -724,6 +860,8 @@ void SettingsWidget::settingsChanged() {
 }
 
 void SettingsWidget::connectAll() {
+    //connect(language_combo, SIGNAL(currentIndexChanged(int)), this, SLOT(updateSettings()));
+    connect(language_combo, SIGNAL(currentIndexChanged(int)), this, SLOT(updateUILanguage(int)));
     connect(mixer_invert_stereo, SIGNAL(clicked()), this, SLOT(updateSettings()));
     connect(mixer_force_mono, SIGNAL(clicked()), this, SLOT(updateSettings()));
     connect(check_args, SIGNAL(clicked()), this, SLOT(updateSettings()));
@@ -798,3 +936,19 @@ void SettingsWidget::connectAll() {
     connect(clear_output_on_run, SIGNAL(clicked()), this, SLOT(clearOutputOnRun()));
     connect(auto_indent_on_run, SIGNAL(clicked()), this, SLOT(autoIndentOnRun()));
 }
+
+void SettingsWidget::add_language_combo_box_entries(QComboBox* combo) {
+  // Add language combo entries
+  std::cout << "[Debug] Adding language combo box entries..." << std::endl;
+  std::cout << (std::to_string(static_cast<int>(available_languages.size()))) << std::endl;
+
+  for (auto const &language : available_languages) {
+    std::cout << "[Debug] Adding language " << language.toUtf8().data() << " to the combo box" << std::endl;
+    if (language != "system_language") {
+      // Add the language's name to the combo box
+      combo->addItem(sonicPii18n->getNativeLanguageName(language));
+    } else {
+      combo->addItem(tr("Use system language"));
+    }
+  }
+}
diff --git a/app/gui/qt/widgets/settingswidget.h b/app/gui/qt/widgets/settingswidget.h
index 5fd983f862..384f686b49 100644
--- a/app/gui/qt/widgets/settingswidget.h
+++ b/app/gui/qt/widgets/settingswidget.h
@@ -2,6 +2,7 @@
 #define SETTINGSWIDGET_H
 
 #include "model/settings.h"
+#include "utils/sonicpi_i18n.h"
 
 #include <QWidget>
 
@@ -23,15 +24,20 @@ class SettingsWidget : public QWidget
     Q_OBJECT
 
 public:
-    SettingsWidget( int server_osc_cues_port, SonicPiSettings *piSettings, QWidget *parent = 0);
+    SettingsWidget(int server_osc_cues_port, bool i18n, SonicPiSettings *piSettings, SonicPii18n *sonicPii18n, QWidget *parent = nullptr);
     ~SettingsWidget();
 
     void updateVersionInfo( QString info_string, QString visit, bool sonic_pi_net_visible, bool check_now_visible);
     void updateMidiInPorts( QString in );
     void updateMidiOutPorts( QString out );
     void updateScopeNames(std::vector<QString>);
+    void updateSelectedUILanguage(QString lang);
+
     QSize sizeHint() const;
 
+public slots:
+    void updateUILanguage(int index);
+
 private slots:
     void update_mixer_invert_stereo();
     void update_mixer_force_mono();
@@ -68,6 +74,8 @@ private slots:
     void autoIndentOnRun();
 
 signals:
+    void restartApp();
+    void uiLanguageChanged(QString lang); // TODO: Implement real-time language switching
     void mixerSettingsChanged();
     void oscSettingsChanged();
     void midiSettingsChanged();
@@ -100,6 +108,10 @@ private slots:
 
 private:
     SonicPiSettings* piSettings;
+    SonicPii18n* sonicPii18n;
+    std::map<QString, QString> localeNames;
+    QStringList available_languages;
+    bool i18n;
     int server_osc_cues_port;
 
     QTabWidget *prefTabs;
@@ -154,13 +166,20 @@ private slots:
     QSlider *system_vol_slider;
     QSlider *gui_transparency_slider;
 
+    QComboBox *language_combo;
+    QLabel *language_option_label;
+    QLabel *language_details_label;
+    QLabel *language_info_label;
+
     // TODO
-    bool i18n = true;
     QGroupBox* createAudioPrefsTab();
     QGroupBox* createIoPrefsTab();
     QGroupBox* createEditorPrefsTab();
     QGroupBox* createVisualizationPrefsTab();
     QGroupBox* createUpdatePrefsTab();
+    QGroupBox* createLanguagePrefsTab();
+
+    void add_language_combo_box_entries(QComboBox* combo);
 
     QString tooltipStrShiftMeta(char key, QString str);
 
diff --git a/app/server/ruby/bin/qt-doc.rb b/app/server/ruby/bin/qt-doc.rb
index 421a192f32..f63b67bec8 100755
--- a/app/server/ruby/bin/qt-doc.rb
+++ b/app/server/ruby/bin/qt-doc.rb
@@ -30,6 +30,63 @@
 
 include SonicPi::Util
 
+# List of all languages with GUI translation files
+@lang_names = Hash[
+  "bg" => "български", # Bulgarian
+  "bn" => "বাংলা", # Bengali/Bangla
+  "bs" => "Bosanski", # Bosnian
+  "ca" => "Català", # Catalan
+  "ca@valencia" => "Valencià", # Valencian
+  "cs" => "Čeština", # Czech
+  "da" => "Dansk", # Danish
+  "de" => "Deutsch", # German
+  "el" => "ελληνικά", # Greek
+  "en" => "English", # English
+  "en_AU" => "English (Australian)", # English (Australian)
+  "en_GB" => "English (UK)", # English (UK) - default language
+  "en_US" => "English (US)", # English (US)
+  "eo" => "Esperanto", # Esperanto
+  "es" => "Español", # Spanish
+  "et" => "Eesti keel", # Estonian
+  "eu" => "Euskara", # Basque
+  "fa" => "فارسی", # Persian
+  "fi" => "Suomi", # Finnish
+  "fr" => "Français", # French
+  "ga" => "Gaeilge", # Irish
+  "gl" => "Galego", # Galician
+  "he" => "עברית", # Hebrew
+  "hi" => "हिन्दी", # Hindi
+  "hu" => "Magyar", # Hungarian
+  "hy" => "Հայերեն", # Armenian
+  "id" => "Bahasa Indonesia", # Indonesian
+  "is" => "Íslenska", # Icelandic
+  "it" => "Italiano", # Italian
+  "ja" => "日本語", # Japanese
+  "ka" => "ქართული", # Georgian
+  "ko" => "한국어", # Korean
+  "nb" => "Norsk Bokmål", # Norwegian Bokmål
+  "nl" => "Nederlands", # Dutch (Netherlands)
+  "pl" => "Polski", # Polish
+  "pt" => "Português", # Portuguese
+  "pt_BR" => "Português do Brasil", # Brazilian Portuguese
+  "ro" => "Română", # Romanian
+  "ru" => "Pусский", # Russian
+  "si" => "සිංහල", # Sinhala/Sinhalese
+  "sk" => "Slovenčina",#/Slovenský Jazyk", # Slovak/Slovakian
+  "sl" => "Slovenščina",#/Slovenski Jezik", # Slovenian
+  "sv" => "Svenska", # Swedish
+  "sw" => "Kiswahili", # Swahili
+  "th" => "ไทย", # Thai
+  "tr" => "Türkçe", # Turkish
+  "ug" => "ئۇيغۇر تىلى", # Uyghur
+  "uk" => "Українська", # Ukranian
+  "vi" => "Tiếng Việt", # Vietnamese
+  "zh" => "中文", # Chinese
+  "zh-Hans" => "简体中文", # Chinese (Simplified)
+  "zh_HK" => "廣東話", # Chinese (Traditional, Hong Kong)
+  "zh_TW" => "臺灣華語" # Chinese (Traditional, Taiwan)
+]
+
 FileUtils::rm_rf "#{qt_gui_path}/help/"
 FileUtils::mkdir "#{qt_gui_path}/help/"
 
@@ -216,11 +273,11 @@
   map { |p| File.basename(p).gsub(/sonic-pi-tutorial-(.*?).po/, '\1') }.
   sort_by {|n| -n.length}
 
-docs << "\n  QString systemLocale = QLocale::system().uiLanguages()[0];\n\n" unless languages.empty?
+docs << "\n"
 
 # first, try to match all non-default languages (those that aren't "en")
 languages.each do |lang|
-  docs << "if (systemLocale.startsWith(\"#{lang}\")) {\n"
+  docs << "if (this->ui_language.startsWith(\"#{lang}\")) {\n"
   make_tutorial.call(lang)
   docs << "} else "
 end
@@ -263,6 +320,41 @@
   docs << "  autocomplete->addSynthArgs(\":#{k}\", fxtmp);\n\n"
 end
 
+def generate_ui_lang_names
+  # Define the language list map -----
+  ui_languages = @lang_names.keys
+  ui_languages = ui_languages.sort_by {|l| l.downcase}
+  locale_arrays = []
+  locale_arrays << "std::map<QString, QString> SonicPii18n::native_language_names = {\n"
+
+  # # Add each language
+  for i in 0..(ui_languages.length()-1) do
+    lang = ui_languages[i]
+    locale_arrays << ",\n" if i != 0
+    locale_arrays << "{\"#{lang}\", \"#{@lang_names[lang]}\"}"
+  end
+
+  # End the map
+  locale_arrays << "\n};\n"
+
+  # Write the map to lang_list.h
+  content = File.readlines("#{qt_gui_path}/utils/lang_list.tmpl")
+  lang_names_generated = content.take_while { |line| !line.start_with?("// AUTO-GENERATED")}
+  lang_names_generated << "// AUTO-GENERATED HEADER FILE\n"
+  lang_names_generated << "// Do not add any code to this file\n"
+  lang_names_generated << "// as it will be removed/overwritten\n"
+  lang_names_generated << "\n"
+  lang_names_generated << "#ifndef LANG_LIST_H\n"
+  lang_names_generated << "#define LANG_LIST_H\n"
+  lang_names_generated << "#include <map>\n"
+  lang_names_generated << locale_arrays.join()
+  lang_names_generated << "#endif\n"
+
+  File.open("#{qt_gui_path}/utils/lang_list.h", 'w') do |f|
+    f << lang_names_generated.join()
+  end
+end
+
 
 # update ruby_help.h
 if options[:output_name] then
@@ -321,3 +413,5 @@
   end
 
 end
+
+generate_ui_lang_names()
diff --git a/app/server/ruby/lib/sonicpi/synths/synthinfo.rb b/app/server/ruby/lib/sonicpi/synths/synthinfo.rb
index 650200152c..162c2ab218 100644
--- a/app/server/ruby/lib/sonicpi/synths/synthinfo.rb
+++ b/app/server/ruby/lib/sonicpi/synths/synthinfo.rb
@@ -3290,6 +3290,214 @@ def arg_defaults
       end
     end
 
+    class WinwoodLead < SonicPiSynth
+      def name
+        "Winwood Lead"
+      end
+
+      def introduced
+        Version.new(3,3,0)
+      end
+
+      def synth_name
+        "winwood_lead"
+      end
+
+      def on_start(studio, args_h)
+        args_h[:rand_buf] = studio.rand_buf_id
+      end
+
+      def doc
+        "A lead synth inspired by the Winwood songs from the early 80s.  Adapted for Sonic Pi from [Steal This Sound](https://raw.githubusercontent.com/supercollider/supercollider/develop/examples/demonstrations/stealthissound.scd). Published there under [GPL v3](https://www.gnu.org/licenses/gpl-3.0.en.html), so re-published under the same terms. The source code is available [on the Sonic Pi GitHub repository](https://github.com/sonic-pi-net/sonic-pi). Date of modification: 10.01.2021"
+      end
+
+      def arg_defaults
+        {
+          :note => 69,
+          :note_slide => 0,
+          :note_slide_shape => 1,
+          :note_slide_curve => 0,
+          :amp => 1,
+          :amp_slide => 0,
+          :amp_slide_shape => 1,
+          :amp_slide_curve => 0,
+          :pan => 0,
+          :pan_slide => 0,
+          :pan_slide_shape => 1,
+          :pan_slide_curve => 0,
+
+          :attack => 0.01,
+          :decay => 0,
+          :sustain => 0.9,
+          :release => 0.05,
+          :attack_level => 1,
+          :decay_level => 0.5,
+          :sustain_level => 0.5,
+
+          :cutoff => 119,
+          :cutoff_slide => 0,
+          :cutoff_slide_shape => 1,
+          :cutoff_slide_curve => 0,
+
+          :res => 0.8,
+          :res_slide => 0,
+          :res_slide_shape => 1,
+          :res_slide_curve => 0,
+          :lfo_width => 0.01,
+          :lfo_width_slide => 0,
+          :lfo_width_slide_shape => 1,
+          :lfo_width_slide_curve => 0,
+          :lfo_rate => 8,
+          :lfo_rate_slide => 0,
+          :lfo_rate_slide_shape => 1,
+          :lfo_rate_slide_curve => 0,
+          :seed => 0,
+        }
+      end
+      
+      def specific_arg_info
+        {
+          :seed =>
+          {
+            :doc => "Seed value for rand num generator used for the phase offset of the triangle low-frequency oscillator (LFO)",
+            :modulatable => false
+          },
+          :lfo_width =>
+          {
+            :doc => "Width of the low-frequency oscillator (LFO) which determines how wide base tones oscillate around their base frequencies",
+            :modulatable => true
+          },
+          :lfo_rate =>
+          {
+            :doc => "Width of the low-frequency oscillator (LFO) which determines how fast base tones oscillate around their base frequencies",
+            :modulatable => true
+          },
+        }
+      end
+    end
+
+    class BassFoundation < SonicPiSynth
+      def name
+        "Bass Foundation"
+      end
+
+      def introduced
+        Version.new(3,3,0)
+      end
+
+      def synth_name
+        "bass_foundation"
+      end
+
+      def doc
+        "A soft bass synth inspired by the sounds of the 80s. Use together with :bass_highend if you want to give it a gargling component. Adapted for Sonic Pi from [Steal This Sound](https://raw.githubusercontent.com/supercollider/supercollider/develop/examples/demonstrations/stealthissound.scd). Published there under [GPL v3](https://www.gnu.org/licenses/gpl-3.0.en.html), so re-published under the same terms. The source code is available [on the Sonic Pi GitHub repository](https://github.com/sonic-pi-net/sonic-pi). Date of modification: 10.01.2021"
+      end
+
+      def arg_defaults
+        {
+          :note => 40,
+          :note_slide => 0,
+          :note_slide_shape => 1,
+          :note_slide_curve => 0,
+          :amp => 1,
+          :amp_slide => 0,
+          :amp_slide_shape => 1,
+          :amp_slide_curve => 0,
+          :pan => 0,
+          :pan_slide => 0,
+          :pan_slide_shape => 1,
+          :pan_slide_curve => 0,
+
+          :attack => 0.01,
+          :decay => 0,
+          :sustain => 0.9,
+          :release => 0.05,
+          :attack_level => 1,
+          :decay_level => 0.5,
+          :sustain_level => 0,
+
+          :cutoff => 83,
+          :cutoff_slide => 0,
+          :cutoff_slide_shape => 1,
+          :cutoff_slide_curve => 0,
+
+          :res => 0.5,
+          :res_slide => 0,
+          :res_slide_shape => 1,
+          :res_slide_curve => 0,
+        }
+      end
+    end
+
+    class BassHighend < SonicPiSynth
+      def name
+        "Bass Highend"
+      end
+
+      def introduced
+        Version.new(3,3,0)
+      end
+
+      def synth_name
+        "bass_highend"
+      end
+
+      def doc
+        "An addition to the :bass_foundation synth inspired by the sounds of the 80s. Use them together if you want to give it a rough, slurping, or gargling component. Adapted for Sonic Pi from [Steal This Sound](https://raw.githubusercontent.com/supercollider/supercollider/develop/examples/demonstrations/stealthissound.scd). Published there under [GPL v3](https://www.gnu.org/licenses/gpl-3.0.en.html), so re-published under the same terms. The source code is available [on the Sonic Pi GitHub repository](https://github.com/sonic-pi-net/sonic-pi). Date of modification: 11.01.2021"
+      end
+
+      def arg_defaults
+        {
+          :note => 40,
+          :note_slide => 0,
+          :note_slide_shape => 1,
+          :note_slide_curve => 0,
+          :amp => 1,
+          :amp_slide => 0,
+          :amp_slide_shape => 1,
+          :amp_slide_curve => 0,
+          :pan => 0,
+          :pan_slide => 0,
+          :pan_slide_shape => 1,
+          :pan_slide_curve => 0,
+
+          :attack => 0.01,
+          :decay => 0,
+          :sustain => 0.9,
+          :release => 0.05,
+          :attack_level => 1,
+          :decay_level => 0.5,
+          :sustain_level => 0,
+
+          :cutoff => 102,
+          :cutoff_slide => 0,
+          :cutoff_slide_shape => 1,
+          :cutoff_slide_curve => 0,
+
+          :res => 0.1,
+          :res_slide => 0,
+          :res_slide_shape => 1,
+          :res_slide_curve => 0,
+
+          :drive => 2.0,
+          :drive_slide => 0,
+          :drive_slide_shape => 1,
+          :drive_slide_curve => 0,
+        }
+      end
+
+      def specific_arg_info
+        {
+          :drive =>
+          {
+            :doc => "Higher drive values make the sound louder and rougher.",
+            :validations => [v_positive(:drive)],
+            :modulatable => true
+            },
+          }
+      end
+    end
+
     class StudioInfo < SonicPiSynth
       def user_facing?
         false
@@ -7949,6 +8157,9 @@ class BaseInfo
         :kalimba => SynthKalimba.new,
         :pluck => SynthPluck.new,
         :tech_saws => TechSaws.new,
+        :winwood_lead => WinwoodLead.new,
+        :bass_foundation => BassFoundation.new,
+        :bass_highend => BassHighend.new,
 
         :sound_in => SoundIn.new,
         :sound_in_stereo => SoundInStereo.new,
diff --git a/etc/synthdefs/compiled/sonic-pi-bass_foundation.scsyndef b/etc/synthdefs/compiled/sonic-pi-bass_foundation.scsyndef
new file mode 100644
index 0000000000..e4cef4d6ba
Binary files /dev/null and b/etc/synthdefs/compiled/sonic-pi-bass_foundation.scsyndef differ
diff --git a/etc/synthdefs/compiled/sonic-pi-bass_highend.scsyndef b/etc/synthdefs/compiled/sonic-pi-bass_highend.scsyndef
new file mode 100644
index 0000000000..633c0d9ed3
Binary files /dev/null and b/etc/synthdefs/compiled/sonic-pi-bass_highend.scsyndef differ
diff --git a/etc/synthdefs/compiled/sonic-pi-winwood_lead.scsyndef b/etc/synthdefs/compiled/sonic-pi-winwood_lead.scsyndef
new file mode 100644
index 0000000000..17b50e0f78
Binary files /dev/null and b/etc/synthdefs/compiled/sonic-pi-winwood_lead.scsyndef differ
diff --git a/etc/synthdefs/designs/supercollider/bass_foundation.scd b/etc/synthdefs/designs/supercollider/bass_foundation.scd
new file mode 100644
index 0000000000..8effc5e139
--- /dev/null
+++ b/etc/synthdefs/designs/supercollider/bass_foundation.scd
@@ -0,0 +1,46 @@
+// Adapted for Sonic Pi from
+//   https://raw.githubusercontent.com/supercollider/supercollider/develop/examples/demonstrations/stealthissound.scd
+// Published there under GPL v3, so re-published under the same terms, see:
+//   https://www.gnu.org/licenses/gpl-3.0.en.html
+// Date of modification: 10.01.2021
+
+(
+SynthDef('sonic-pi-bass_foundation', {|
+	note = 40, note_slide = 0, note_slide_shape = 1, note_slide_curve = 0,
+	amp = 1, amp_slide = 0, amp_slide_shape = 1, amp_slide_curve = 0,
+	pan = 0, pan_slide = 0, pan_slide_shape = 1, pan_slide_curve = 0,
+	attack = 0.01, decay = 0, sustain = 0.9, release = 0.05,
+	attack_level = 1, decay_level = 0.5, sustain_level = 0,
+	cutoff = 83, cutoff_slide = 0, cutoff_slide_shape = 1, cutoff_slide_curve = 0,
+	res = 0.5, res_slide = 0, res_slide_shape = 1, res_slide_curve = 0,
+	out_bus = 0|
+
+	var snd, osc, env, filterenv;
+
+	note = note.midicps;
+	note = note.varlag(note_slide, note_slide_curve, note_slide_shape);
+	decay_level = Select.kr(decay_level < 0, [decay_level, sustain_level]);
+	amp = amp.varlag(amp_slide, amp_slide_curve, amp_slide_shape);
+	pan = pan.varlag(pan_slide, pan_slide_curve, pan_slide_shape);
+
+	cutoff = cutoff.midicps;
+    cutoff = cutoff.varlag(cutoff_slide, cutoff_slide_curve, cutoff_slide_shape);
+
+	res = res.varlag(res_slide, res_slide_curve, res_slide_shape);
+
+	osc = Saw.ar(note);
+
+	filterenv = EnvGen.ar(Env.adsr(0.0, 0.5, 0.2, 0.2), 1, doneAction:2);
+	snd =  RLPF.ar(osc,cutoff*filterenv+100, res);
+
+	env = Env.new(
+		[0, attack_level, decay_level, sustain_level, 0],
+		[attack,decay,sustain,release],
+		\lin
+	);
+
+	snd = Pan2.ar(Mix(snd) * EnvGen.kr(env, doneAction: 2), pan);
+
+	Out.ar(out_bus, snd * amp);
+}).writeDefFile("/Users/sam/Development/RPi/sonic-pi/etc/synthdefs/compiled/");
+)
\ No newline at end of file
diff --git a/etc/synthdefs/designs/supercollider/bass_highend.scd b/etc/synthdefs/designs/supercollider/bass_highend.scd
new file mode 100644
index 0000000000..a73c8421d1
--- /dev/null
+++ b/etc/synthdefs/designs/supercollider/bass_highend.scd
@@ -0,0 +1,58 @@
+// Adapted for Sonic Pi from
+//   https://raw.githubusercontent.com/supercollider/supercollider/develop/examples/demonstrations/stealthissound.scd
+// Published there under GPL v3, so re-published under the same terms, see:
+//   https://www.gnu.org/licenses/gpl-3.0.en.html
+// Date of modification: 11.01.2021
+
+(
+SynthDef('sonic-pi-bass_highend',{|
+	note = 40, note_slide = 0, note_slide_shape = 1, note_slide_curve = 0,
+	amp = 1, amp_slide = 0, amp_slide_shape = 1, amp_slide_curve = 0,
+	pan = 0, pan_slide = 0, pan_slide_shape = 1, pan_slide_curve = 0,
+	attack = 0.01, decay = 0, sustain = 0.9, release = 0.05,
+	attack_level = 1, decay_level = 0.5, sustain_level = 0,
+	cutoff = 102, cutoff_slide = 0, cutoff_slide_shape = 1, cutoff_slide_curve = 0,
+	res = 0.1, res_slide = 0, res_slide_shape = 1, res_slide_curve = 0,
+	drive = 2.0, drive_slide = 0, drive_slide_shape = 1, drive_slide_curve = 0,
+	out_bus = 0|
+
+	var osc, snd, env, filterenv, ab;
+
+	note = note.midicps;
+	note = note.varlag(note_slide, note_slide_curve, note_slide_shape);
+	decay_level = Select.kr(decay_level < 0, [decay_level, sustain_level]);
+	amp = amp.varlag(amp_slide, amp_slide_curve, amp_slide_shape);
+	pan = pan.varlag(pan_slide, pan_slide_curve, pan_slide_shape);
+
+	cutoff = cutoff.midicps;
+	cutoff = cutoff.varlag(cutoff_slide, cutoff_slide_curve, cutoff_slide_shape);
+
+	res = res.varlag(res_slide, res_slide_curve, res_slide_shape);
+
+	drive = drive.varlag(drive_slide, drive_slide_curve, drive_slide_shape);
+
+	osc = Mix(Saw.ar(note*[0.25,1,1.5],[0.5,0.4,0.1]));
+	filterenv = EnvGen.ar(Env.adsr(0.0,0.5,0.2,0.2), doneAction:2);
+	snd =  RLPF.ar(osc,cutoff*filterenv+100,res);
+
+	ab = abs(snd);
+	snd = (snd*(ab + drive)/(snd ** 2 + (drive - 1) * ab + 1));
+
+	// Remove low end
+	snd = BLowShelf.ar(snd, 300, 1.0, -12);
+
+	// Dip at 1600Hz
+	snd = BPeakEQ.ar(snd, 1600, 1.0, -6);
+
+	env = Env.new(
+		[0, attack_level, decay_level, sustain_level, 0],
+		[attack,decay,sustain,release],
+		\lin
+	);
+
+	snd = Pan2.ar(Mix(snd) * EnvGen.kr(env, doneAction: 2) * 2, pan);
+
+	Out.ar(out_bus, snd * amp);
+
+}).writeDefFile("/Users/sam/Development/RPi/sonic-pi/etc/synthdefs/compiled/");
+)
\ No newline at end of file
diff --git a/etc/synthdefs/designs/supercollider/winwood_lead.scd b/etc/synthdefs/designs/supercollider/winwood_lead.scd
new file mode 100644
index 0000000000..8f544ffb22
--- /dev/null
+++ b/etc/synthdefs/designs/supercollider/winwood_lead.scd
@@ -0,0 +1,58 @@
+// Adapted for Sonic Pi from
+//   https://raw.githubusercontent.com/supercollider/supercollider/develop/examples/demonstrations/stealthissound.scd
+// Published there under GPL v3, so re-published under the same terms, see:
+//   https://www.gnu.org/licenses/gpl-3.0.en.html
+// Date of modification: 10.01.2021
+
+(
+SynthDef('sonic-pi-winwood_lead', {|
+	note = 69, note_slide = 0, note_slide_shape = 1, note_slide_curve = 0,
+	amp = 1, amp_slide = 0, amp_slide_shape = 1, amp_slide_curve = 0,
+	pan = 0, pan_slide = 0, pan_slide_shape = 1, pan_slide_curve = 0,
+	attack = 0.01, decay = 0, sustain = 0.9, release = 0.05,
+	attack_level = 1, decay_level = 0.5, sustain_level = 0.5,
+	cutoff = 119, cutoff_slide = 0, cutoff_slide_shape = 1, cutoff_slide_curve = 0,
+	lfo_width = 0.01, lfo_width_slide = 0, lfo_width_slide_shape = 1, lfo_width_slide_curve = 0,
+	lfo_rate = 8, lfo_rate_slide = 0, lfo_rate_slide_shape = 1, lfo_rate_slide_curve = 0,
+	res = 0.8, res_slide = 0, res_slide_shape = 1, res_slide_curve = 0,
+	seed = 0, rand_buf = 0,
+	out_bus = 0|
+
+	var snd, pulse, env, lfo;
+	var rand_val;
+
+	note = note.midicps;
+	note = note.varlag(note_slide, note_slide_curve, note_slide_shape);
+	decay_level = Select.kr(decay_level < 0, [decay_level, sustain_level]);
+	amp = amp.varlag(amp_slide, amp_slide_curve, amp_slide_shape);
+	pan = pan.varlag(pan_slide, pan_slide_curve, pan_slide_shape);
+
+	cutoff = cutoff.midicps;
+	cutoff = cutoff.varlag(cutoff_slide, cutoff_slide_curve, cutoff_slide_shape);
+
+	lfo_width = lfo_width.varlag(lfo_width_slide, lfo_width_slide_curve, lfo_width_slide_shape);
+	lfo_rate = lfo_rate.varlag(lfo_rate_slide, lfo_rate_slide_curve, lfo_rate_slide_shape);
+
+	res = res.varlag(res_slide, res_slide_curve, res_slide_shape);
+
+	rand_val = BufRd.kr(1, rand_buf, seed, 1);
+
+	lfo = LFTri.kr(lfo_rate,(rand_val*2.0)!2);
+
+	pulse = Mix(Pulse.ar(note*[1,1.001]*(1.0+(lfo_width*lfo)),[0.2,0.19]))*0.5;
+
+	snd =  RLPF.ar(pulse,cutoff,res);
+
+	snd = BLowShelf.ar(snd,351,1.0,-9);
+
+	env = Env.new(
+		[0, attack_level, decay_level, sustain_level, 0],
+		[attack,decay,sustain,release],
+		\lin
+	);
+
+	snd = Pan2.ar(Mix(snd) * EnvGen.kr(env, doneAction: 2), pan);
+
+	Out.ar(out_bus, snd * amp);
+}).writeDefFile("/Users/sam/Development/RPi/sonic-pi/etc/synthdefs/compiled/");
+)
\ No newline at end of file