diff --git a/ecp5/arch.h b/ecp5/arch.h
index cd103b12..6daf543d 100644
--- a/ecp5/arch.h
+++ b/ecp5/arch.h
@@ -384,7 +384,7 @@ struct PipRange
 
 struct ArchArgs
 {
-    enum
+    enum ArchArgsTypes
     {
         NONE,
         LFE5U_25F,
diff --git a/ecp5/main.cc b/ecp5/main.cc
index dac7a635..dde3ffed 100644
--- a/ecp5/main.cc
+++ b/ecp5/main.cc
@@ -148,7 +148,7 @@ int main(int argc, char *argv[])
 #ifndef NO_GUI
         if (vm.count("gui")) {
             Application a(argc, argv);
-            MainWindow w(std::move(ctx));
+            MainWindow w(std::move(ctx),args);
             w.show();
 
             return a.exec();
diff --git a/generic/arch.cc b/generic/arch.cc
index f9133f9e..7c0828e0 100644
--- a/generic/arch.cc
+++ b/generic/arch.cc
@@ -175,7 +175,7 @@ void Arch::setGroupDecal(GroupId group, DecalXY decalxy)
 
 // ---------------------------------------------------------------
 
-Arch::Arch(ArchArgs) {}
+Arch::Arch(ArchArgs) : chipName("generic") {}
 
 void IdString::initialize_arch(const BaseCtx *ctx) {}
 
diff --git a/generic/main.cc b/generic/main.cc
index 3b8b3fe6..8653da01 100644
--- a/generic/main.cc
+++ b/generic/main.cc
@@ -90,7 +90,8 @@ int main(int argc, char *argv[])
             return 1;
         }
 
-        std::unique_ptr<Context> ctx = std::unique_ptr<Context>(new Context(ArchArgs{}));
+        ArchArgs chipArgs{};
+        std::unique_ptr<Context> ctx = std::unique_ptr<Context>(new Context(chipArgs));
 
         if (vm.count("verbose")) {
             ctx->verbose = true;
@@ -107,7 +108,7 @@ int main(int argc, char *argv[])
 #ifndef NO_GUI
         if (vm.count("gui")) {
             Application a(argc, argv);
-            MainWindow w(std::move(ctx));
+            MainWindow w(std::move(ctx), chipArgs);
             w.show();
 
             return a.exec();
diff --git a/gui/basewindow.cc b/gui/basewindow.cc
index 37141fd6..53720156 100644
--- a/gui/basewindow.cc
+++ b/gui/basewindow.cc
@@ -37,8 +37,8 @@ static void initBasenameResource() { Q_INIT_RESOURCE(base); }
 
 NEXTPNR_NAMESPACE_BEGIN
 
-BaseMainWindow::BaseMainWindow(std::unique_ptr<Context> context, QWidget *parent)
-        : QMainWindow(parent), ctx(std::move(context)), timing_driven(false)
+BaseMainWindow::BaseMainWindow(std::unique_ptr<Context> context, ArchArgs args, QWidget *parent)
+        : QMainWindow(parent), chipArgs(args), ctx(std::move(context)), timing_driven(false)
 {
     initBasenameResource();
     qRegisterMetaType<std::string>();
diff --git a/gui/basewindow.h b/gui/basewindow.h
index 5cec24c5..341cc8e2 100644
--- a/gui/basewindow.h
+++ b/gui/basewindow.h
@@ -45,7 +45,7 @@ class BaseMainWindow : public QMainWindow
     Q_OBJECT
 
   public:
-    explicit BaseMainWindow(std::unique_ptr<Context> context, QWidget *parent = 0);
+    explicit BaseMainWindow(std::unique_ptr<Context> context, ArchArgs args, QWidget *parent = 0);
     virtual ~BaseMainWindow();
     Context *getContext() { return ctx.get(); }
 
@@ -88,6 +88,7 @@ class BaseMainWindow : public QMainWindow
 
   protected:
     // state variables
+    ArchArgs chipArgs;
     std::unique_ptr<Context> ctx;
     TaskManager *task;
     bool timing_driven;
diff --git a/gui/ecp5/mainwindow.cc b/gui/ecp5/mainwindow.cc
index 935daefd..efaad364 100644
--- a/gui/ecp5/mainwindow.cc
+++ b/gui/ecp5/mainwindow.cc
@@ -18,30 +18,148 @@
  */
 
 #include "mainwindow.h"
+#include "bitstream.h"
+#include "log.h"
+
+#include <QFileDialog>
+#include <QInputDialog>
+#include <QLineEdit>
 
 static void initMainResource() { Q_INIT_RESOURCE(nextpnr); }
 
 NEXTPNR_NAMESPACE_BEGIN
 
-MainWindow::MainWindow(std::unique_ptr<Context> context, QWidget *parent) : BaseMainWindow(std::move(context), parent)
+MainWindow::MainWindow(std::unique_ptr<Context> context, ArchArgs args, QWidget *parent) : BaseMainWindow(std::move(context), args, parent)
 {
     initMainResource();
 
     std::string title = "nextpnr-ecp5 - [EMPTY]";
     setWindowTitle(title.c_str());
 
+    connect(this, &BaseMainWindow::contextChanged, this, &MainWindow::newContext);
+
     createMenu();
     Q_EMIT contextChanged(ctx.get());
 }
 
 MainWindow::~MainWindow() {}
 
-void MainWindow::createMenu() {}
+void MainWindow::newContext(Context *ctx)
+{
+    std::string title = "nextpnr-generic - " + ctx->getChipName() + " ( " + chipArgs.package + " )";
+    setWindowTitle(title.c_str());
+}
 
-void MainWindow::new_proj() {}
+void MainWindow::createMenu() {
+    // Add arch specific actions
+    actionLoadBase = new QAction("Open Base Config", this);
+    actionLoadBase->setIcon(QIcon(":/icons/resources/open_base.png"));
+    actionLoadBase->setStatusTip("Open Base Config file");
+    actionLoadBase->setEnabled(false);
+    connect(actionLoadBase, &QAction::triggered, this, &MainWindow::open_base);
+
+    actionSaveConfig = new QAction("Save Bitstream", this);
+    actionSaveConfig->setIcon(QIcon(":/icons/resources/save_config.png"));
+    actionSaveConfig->setStatusTip("Save Bitstream config file");
+    actionSaveConfig->setEnabled(false);
+    connect(actionSaveConfig, &QAction::triggered, this, &MainWindow::save_config);
+
+    // Add actions in menus
+    mainActionBar->addSeparator();
+    mainActionBar->addAction(actionLoadBase);
+    mainActionBar->addAction(actionSaveConfig);
+
+    menuDesign->addSeparator();
+    menuDesign->addAction(actionLoadBase);
+    menuDesign->addAction(actionSaveConfig);    
+}
+
+static const ChipInfoPOD *get_chip_info(const RelPtr<ChipInfoPOD> *ptr) { return ptr->get(); }
+
+static QStringList getSupportedPackages(ArchArgs::ArchArgsTypes chip)
+{
+    QStringList packages;
+    const ChipInfoPOD *chip_info;
+    if (chip == ArchArgs::LFE5U_25F) {
+        chip_info = get_chip_info(reinterpret_cast<const RelPtr<ChipInfoPOD> *>(chipdb_blob_25k));
+    } else if (chip == ArchArgs::LFE5U_45F) {
+        chip_info = get_chip_info(reinterpret_cast<const RelPtr<ChipInfoPOD> *>(chipdb_blob_45k));
+    } else if (chip == ArchArgs::LFE5U_85F) {
+        chip_info = get_chip_info(reinterpret_cast<const RelPtr<ChipInfoPOD> *>(chipdb_blob_85k));
+    } else {
+        log_error("Unsupported ECP5 chip type.\n");
+    }
+
+    for (int i = 0; i < chip_info->num_packages; i++) {
+        packages << chip_info->package_info[i].name.get();
+    }
+    return packages;
+}
+
+
+void MainWindow::new_proj() {
+    QMap<QString, int> arch;
+    arch.insert("Lattice ECP5 25K", ArchArgs::LFE5U_25F);
+    arch.insert("Lattice ECP5 45K", ArchArgs::LFE5U_45F);
+    arch.insert("Lattice ECP5 85K", ArchArgs::LFE5U_85F);
+    bool ok;
+    QString item = QInputDialog::getItem(this, "Select new context", "Chip:", arch.keys(), 0, false, &ok);
+    if (ok && !item.isEmpty()) {
+
+        chipArgs.type = (ArchArgs::ArchArgsTypes)arch.value(item);
+
+        QString package = QInputDialog::getItem(this, "Select package", "Package:", getSupportedPackages(chipArgs.type),
+                                                0, false, &ok);
+
+        if (ok && !item.isEmpty()) {
+            currentProj = "";
+            currentJson = "";
+            disableActions();
+            chipArgs.package = package.toStdString().c_str();
+            ctx = std::unique_ptr<Context>(new Context(chipArgs));
+            actionLoadJSON->setEnabled(true);
+
+            Q_EMIT contextChanged(ctx.get());
+        }
+    }
+}
 
 void MainWindow::open_proj() {}
 
 bool MainWindow::save_proj() { return false; }
 
+void MainWindow::load_base_config(std::string filename)
+{
+    disableActions();
+    currentBaseConfig = filename;
+    actionSaveConfig->setEnabled(true);
+}
+
+void MainWindow::open_base()
+{
+    QString fileName = QFileDialog::getOpenFileName(this, QString("Open Base Config"), QString(), QString("*.config"));
+    if (!fileName.isEmpty()) {
+        load_base_config(fileName.toStdString());
+    }
+}
+
+void MainWindow::save_config()
+{
+    QString fileName = QFileDialog::getSaveFileName(this, QString("Save Bitstream"), QString(), QString("*.config"));
+    if (!fileName.isEmpty()) {
+        std::string fn = fileName.toStdString();
+        disableActions();
+        write_bitstream(ctx.get(), currentBaseConfig, fileName.toStdString());
+        log("Saving Bitstream successful.\n");
+    }
+}
+
+void MainWindow::onDisableActions()
+{
+    actionLoadBase->setEnabled(false);
+    actionSaveConfig->setEnabled(false);
+}
+
+void MainWindow::onRouteFinished() { actionLoadBase->setEnabled(true); }
+
 NEXTPNR_NAMESPACE_END
diff --git a/gui/ecp5/mainwindow.h b/gui/ecp5/mainwindow.h
index e97bb4e7..d1d5a5a2 100644
--- a/gui/ecp5/mainwindow.h
+++ b/gui/ecp5/mainwindow.h
@@ -29,16 +29,32 @@ class MainWindow : public BaseMainWindow
     Q_OBJECT
 
   public:
-    explicit MainWindow(std::unique_ptr<Context> context, QWidget *parent = 0);
+    explicit MainWindow(std::unique_ptr<Context> context, ArchArgs args, QWidget *parent = 0);
     virtual ~MainWindow();
 
   public:
     void createMenu();
+    void load_base_config(std::string filename);
+
+  protected:
+    void onDisableActions() override;
+    void onRouteFinished() override;
 
   protected Q_SLOTS:
     virtual void new_proj();
     virtual void open_proj();
     virtual bool save_proj();
+    void newContext(Context *ctx);
+    void open_base();
+    void save_config();
+  private:
+    QAction *actionLoadBase;
+    QAction *actionSaveConfig;
+
+    ArchArgs chipArgs;
+
+    std::string currentProj;
+    std::string currentBaseConfig;
 };
 
 NEXTPNR_NAMESPACE_END
diff --git a/gui/ecp5/nextpnr.qrc b/gui/ecp5/nextpnr.qrc
index 03585ec0..09f96d74 100644
--- a/gui/ecp5/nextpnr.qrc
+++ b/gui/ecp5/nextpnr.qrc
@@ -1,2 +1,6 @@
 <RCC>
+    <qresource prefix="/icons">
+        <file>resources/open_base.png</file>
+        <file>resources/save_config.png</file>
+    </qresource>
 </RCC>
diff --git a/gui/ecp5/resources/open_base.png b/gui/ecp5/resources/open_base.png
new file mode 100644
index 00000000..d58d226c
Binary files /dev/null and b/gui/ecp5/resources/open_base.png differ
diff --git a/gui/ecp5/resources/save_config.png b/gui/ecp5/resources/save_config.png
new file mode 100644
index 00000000..2ade7128
Binary files /dev/null and b/gui/ecp5/resources/save_config.png differ
diff --git a/gui/generic/mainwindow.cc b/gui/generic/mainwindow.cc
index 70ee600d..050c0fb8 100644
--- a/gui/generic/mainwindow.cc
+++ b/gui/generic/mainwindow.cc
@@ -23,19 +23,27 @@ static void initMainResource() { Q_INIT_RESOURCE(nextpnr); }
 
 NEXTPNR_NAMESPACE_BEGIN
 
-MainWindow::MainWindow(std::unique_ptr<Context> context, QWidget *parent) : BaseMainWindow(std::move(context), parent)
+MainWindow::MainWindow(std::unique_ptr<Context> context, ArchArgs args, QWidget *parent) : BaseMainWindow(std::move(context), args, parent)
 {
     initMainResource();
 
     std::string title = "nextpnr-generic - [EMPTY]";
     setWindowTitle(title.c_str());
 
+    connect(this, &BaseMainWindow::contextChanged, this, &MainWindow::newContext);
+
     createMenu();
     Q_EMIT contextChanged(ctx.get());
 }
 
 MainWindow::~MainWindow() {}
 
+void MainWindow::newContext(Context *ctx)
+{
+    std::string title = "nextpnr-generic - " + ctx->getChipName();
+    setWindowTitle(title.c_str());
+}
+
 void MainWindow::createMenu() {}
 
 void MainWindow::new_proj() {}
diff --git a/gui/generic/mainwindow.h b/gui/generic/mainwindow.h
index e97bb4e7..375436b6 100644
--- a/gui/generic/mainwindow.h
+++ b/gui/generic/mainwindow.h
@@ -29,7 +29,7 @@ class MainWindow : public BaseMainWindow
     Q_OBJECT
 
   public:
-    explicit MainWindow(std::unique_ptr<Context> context, QWidget *parent = 0);
+    explicit MainWindow(std::unique_ptr<Context> context, ArchArgs args, QWidget *parent = 0);
     virtual ~MainWindow();
 
   public:
@@ -39,6 +39,7 @@ class MainWindow : public BaseMainWindow
     virtual void new_proj();
     virtual void open_proj();
     virtual bool save_proj();
+    void newContext(Context *ctx);
 };
 
 NEXTPNR_NAMESPACE_END
diff --git a/gui/ice40/mainwindow.cc b/gui/ice40/mainwindow.cc
index 2fa2e561..40b863e9 100644
--- a/gui/ice40/mainwindow.cc
+++ b/gui/ice40/mainwindow.cc
@@ -37,7 +37,7 @@ static void initMainResource() { Q_INIT_RESOURCE(nextpnr); }
 NEXTPNR_NAMESPACE_BEGIN
 
 MainWindow::MainWindow(std::unique_ptr<Context> context, ArchArgs args, QWidget *parent)
-        : BaseMainWindow(std::move(context), parent), chipArgs(args)
+        : BaseMainWindow(std::move(context), args, parent)
 {
     initMainResource();
 
@@ -78,18 +78,11 @@ void MainWindow::createMenu()
     menuDesign->addAction(actionSaveAsc);
 }
 
-#if defined(_MSC_VER)
-void load_chipdb();
-#endif
-
 static const ChipInfoPOD *get_chip_info(const RelPtr<ChipInfoPOD> *ptr) { return ptr->get(); }
 
-QStringList getSupportedPackages(ArchArgs::ArchArgsTypes chip)
+static QStringList getSupportedPackages(ArchArgs::ArchArgsTypes chip)
 {
     QStringList packages;
-#if defined(_MSC_VER)
-    load_chipdb();
-#endif
     const ChipInfoPOD *chip_info;
 #ifdef ICE40_HX1K_ONLY
     if (chip == ArchArgs::HX1K) {
diff --git a/gui/ice40/mainwindow.h b/gui/ice40/mainwindow.h
index 230ccc4e..829375e2 100644
--- a/gui/ice40/mainwindow.h
+++ b/gui/ice40/mainwindow.h
@@ -55,8 +55,6 @@ class MainWindow : public BaseMainWindow
     QAction *actionLoadPCF;
     QAction *actionSaveAsc;
 
-    ArchArgs chipArgs;
-
     std::string currentProj;
     std::string currentPCF;
 };