diff --git a/CMakeLists.txt b/CMakeLists.txt
index 2cf15c31..84090a07 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -152,6 +152,7 @@ target_link_libraries(kaizen PUBLIC imgui SDL3::SDL3 SDL3::SDL3-static cflags::c
 target_compile_definitions(kaizen PUBLIC SDL_MAIN_HANDLED)
 
 if (SANITIZERS)
+  message("UBSAN AND ASAN: ON")
   target_compile_options(kaizen PUBLIC -fsanitize=undefined -fsanitize=address)
   target_link_options(kaizen PUBLIC -fsanitize=undefined -fsanitize=address)
 endif ()
diff --git a/external/parallel-rdp/ParallelRDPWrapper.cpp b/external/parallel-rdp/ParallelRDPWrapper.cpp
index 32c33097..3b4bff54 100644
--- a/external/parallel-rdp/ParallelRDPWrapper.cpp
+++ b/external/parallel-rdp/ParallelRDPWrapper.cpp
@@ -6,14 +6,13 @@
 #include <resources/frag.spv.h>
 #include <KaizenGui.hpp>
 #include <imgui_impl_vulkan.h>
-#include <mutex>
 
 using namespace Vulkan;
 using namespace RDP;
 
 bool ParallelRDP::IsFramerateUnlocked() const { return wsi->get_present_mode() != PresentMode::SyncToVBlank; }
 
-void ParallelRDP::SetFramerateUnlocked(bool unlocked) const {
+void ParallelRDP::SetFramerateUnlocked(const bool unlocked) const {
   if (unlocked) {
     wsi->set_present_mode(PresentMode::UnlockedForceTearing);
   } else {
@@ -24,11 +23,11 @@ void ParallelRDP::SetFramerateUnlocked(bool unlocked) const {
 Program *fullscreen_quad_program;
 
 // Copied and modified from WSI::init_context_from_platform
-Util::IntrusivePtr<Context> InitVulkanContext(WSIPlatform *platform, unsigned num_thread_indices,
+Util::IntrusivePtr<Context> InitVulkanContext(WSIPlatform *platform, const unsigned num_thread_indices,
                                               const Context::SystemHandles &system_handles) {
   VK_ASSERT(platform);
-  auto instance_ext = platform->get_instance_extensions();
-  auto device_ext = platform->get_device_extensions();
+  const auto instance_ext = platform->get_instance_extensions();
+  const auto device_ext = platform->get_device_extensions();
   auto new_context = Util::make_handle<Context>();
 
   new_context->set_application_info(platform->get_application_info());
@@ -39,9 +38,9 @@ Util::IntrusivePtr<Context> InitVulkanContext(WSIPlatform *platform, unsigned nu
     panic("Failed to create Vulkan instance.\n");
   }
 
-  VkSurfaceKHR tmp_surface = platform->create_surface(new_context->get_instance(), VK_NULL_HANDLE);
+  const auto tmp_surface = platform->create_surface(new_context->get_instance(), VK_NULL_HANDLE);
 
-  bool ret = new_context->init_device(VK_NULL_HANDLE, tmp_surface, device_ext.data(), device_ext.size(),
+  const bool ret = new_context->init_device(VK_NULL_HANDLE, tmp_surface, device_ext.data(), device_ext.size(),
                                       CONTEXT_CREATION_ENABLE_ADVANCED_WSI_BIT);
 
   if (tmp_surface) {
@@ -61,9 +60,9 @@ void ParallelRDP::LoadWSIPlatform(const std::shared_ptr<WSIPlatform> &wsi_platfo
   wsi->set_backbuffer_srgb(false);
   wsi->set_platform(wsi_platform.get());
   wsi->set_present_mode(PresentMode::SyncToVBlank);
-  Context::SystemHandles handles;
 
-  if (!wsi->init_from_existing_context(InitVulkanContext(wsi_platform.get(), 1, handles))) {
+  if (constexpr Context::SystemHandles handles;
+      !wsi->init_from_existing_context(InitVulkanContext(wsi_platform.get(), 1, handles))) {
     panic("Failed to initialize WSI: init_from_existing_context() failed");
   }
 
@@ -97,8 +96,8 @@ void ParallelRDP::Init(const std::shared_ptr<WSIPlatform> &wsiPlatform,
   fragLayout.sets[0].fp_mask = 1;
   fragLayout.sets[0].array_size[0] = 1;
 
-  auto sizeVert = sizeof(vertex_shader);
-  auto sizeFrag = sizeof(fragment_shader);
+  constexpr auto sizeVert = sizeof(vertex_shader);
+  constexpr auto sizeFrag = sizeof(fragment_shader);
 
   fullscreen_quad_program = wsi->get_device().request_program(
     reinterpret_cast<const u32 *>(vertex_shader), sizeVert, reinterpret_cast<const u32 *>(fragment_shader),
@@ -108,8 +107,8 @@ void ParallelRDP::Init(const std::shared_ptr<WSIPlatform> &wsiPlatform,
   uintptr_t offset = 0;
 
   if (wsi->get_device().get_device_features().supports_external_memory_host) {
-    size_t align = wsi->get_device().get_device_features().host_memory_properties.minImportedHostPointerAlignment;
-    offset = aligned_rdram & (align - 1);
+    const size_t align = wsi->get_device().get_device_features().host_memory_properties.minImportedHostPointerAlignment;
+    offset = aligned_rdram & align - 1;
     aligned_rdram -= offset;
   }
 
@@ -128,7 +127,7 @@ void ParallelRDP::DrawFullscreenTexturedQuad(Util::IntrusivePtr<Image> image,
   cmd->set_texture(0, 0, image->get_view(), StockSampler::LinearClamp);
   cmd->set_program(fullscreen_quad_program);
   cmd->set_quad_state();
-  auto data = static_cast<float *>(cmd->allocate_vertex_data(0, 6 * sizeof(float), 2 * sizeof(float)));
+  const auto data = static_cast<float *>(cmd->allocate_vertex_data(0, 6 * sizeof(float), 2 * sizeof(float)));
   data[0] = -1.0f;
   data[1] = -3.0f;
   data[2] = -1.0f;
@@ -136,15 +135,15 @@ void ParallelRDP::DrawFullscreenTexturedQuad(Util::IntrusivePtr<Image> image,
   data[4] = +3.0f;
   data[5] = +1.0f;
 
-  auto windowSize = windowInfo->get_window_size();
+  const auto [x, y] = windowInfo->get_window_size();
 
-  float zoom = std::min(windowSize.x / wsi->get_platform().get_surface_width(),
-                        windowSize.y / wsi->get_platform().get_surface_height());
+  const float zoom = std::min(x / static_cast<float>(wsi->get_platform().get_surface_width()),
+                        y / static_cast<float>(wsi->get_platform().get_surface_height()));
 
-  float width = (wsi->get_platform().get_surface_width() / windowSize.x) * zoom;
-  float height = (wsi->get_platform().get_surface_height() / windowSize.y) * zoom;
+  const float width = static_cast<float>(wsi->get_platform().get_surface_width()) / x * zoom;
+  const float height = static_cast<float>(wsi->get_platform().get_surface_height()) / y * zoom;
 
-  float uniform_data[] = {// Size
+  const float uniform_data[] = {// Size
                           width, height,
                           // Offset
                           (1.0f - width) * 0.5f, (1.0f - height) * 0.5f};
@@ -190,43 +189,43 @@ void ParallelRDP::UpdateScreen(Util::IntrusivePtr<Image> image) const {
   wsi->end_frame();
 }
 
-void ParallelRDP::UpdateScreen(bool playing) const {  
-  if(playing) {
-    n64::Core& core = n64::Core::GetInstance();
-    n64::VI& vi = core.GetMem().mmio.vi;
-    command_processor->set_vi_register(VIRegister::Control, vi.status.raw);
-    command_processor->set_vi_register(VIRegister::Origin, vi.origin);
-    command_processor->set_vi_register(VIRegister::Width, vi.width);
-    command_processor->set_vi_register(VIRegister::Intr, vi.intr);
-    command_processor->set_vi_register(VIRegister::VCurrentLine, vi.current);
-    command_processor->set_vi_register(VIRegister::Timing, vi.burst.raw);
-    command_processor->set_vi_register(VIRegister::VSync, vi.vsync);
-    command_processor->set_vi_register(VIRegister::HSync, vi.hsync);
-    command_processor->set_vi_register(VIRegister::Leap, vi.hsyncLeap.raw);
-    command_processor->set_vi_register(VIRegister::HStart, vi.hstart.raw);
-    command_processor->set_vi_register(VIRegister::VStart, vi.vstart.raw);
-    command_processor->set_vi_register(VIRegister::VBurst, vi.vburst);
-    command_processor->set_vi_register(VIRegister::XScale, vi.xscale.raw);
-    command_processor->set_vi_register(VIRegister::YScale, vi.yscale.raw);
-    ScanoutOptions opts;
-    opts.persist_frame_on_invalid_input = true;
-    opts.vi.aa = true;
-    opts.vi.scale = true;
-    opts.vi.dither_filter = true;
-    opts.vi.divot_filter = true;
-    opts.vi.gamma_dither = true;
-    opts.downscale_steps = true;
-    opts.crop_overscan_pixels = true;
-    Util::IntrusivePtr<Image> image = command_processor->scanout(opts);
-    UpdateScreen(image);
-    command_processor->begin_frame_context();
-    return;
-  }
-  
+template <>
+void ParallelRDP::UpdateScreen<true>() const {
+  const n64::VI& vi = n64::Core::GetMem().mmio.vi;
+  command_processor->set_vi_register(VIRegister::Control, vi.status.raw);
+  command_processor->set_vi_register(VIRegister::Origin, vi.origin);
+  command_processor->set_vi_register(VIRegister::Width, vi.width);
+  command_processor->set_vi_register(VIRegister::Intr, vi.intr);
+  command_processor->set_vi_register(VIRegister::VCurrentLine, vi.current);
+  command_processor->set_vi_register(VIRegister::Timing, vi.burst.raw);
+  command_processor->set_vi_register(VIRegister::VSync, vi.vsync);
+  command_processor->set_vi_register(VIRegister::HSync, vi.hsync);
+  command_processor->set_vi_register(VIRegister::Leap, vi.hsyncLeap.raw);
+  command_processor->set_vi_register(VIRegister::HStart, vi.hstart.raw);
+  command_processor->set_vi_register(VIRegister::VStart, vi.vstart.raw);
+  command_processor->set_vi_register(VIRegister::VBurst, vi.vburst);
+  command_processor->set_vi_register(VIRegister::XScale, vi.xscale.raw);
+  command_processor->set_vi_register(VIRegister::YScale, vi.yscale.raw);
+  ScanoutOptions opts;
+  opts.persist_frame_on_invalid_input = true;
+  opts.vi.aa = true;
+  opts.vi.scale = true;
+  opts.vi.dither_filter = true;
+  opts.vi.divot_filter = true;
+  opts.vi.gamma_dither = true;
+  opts.downscale_steps = true;
+  opts.crop_overscan_pixels = true;
+  const Util::IntrusivePtr<Image> image = command_processor->scanout(opts);
+  UpdateScreen(image);
+  command_processor->begin_frame_context();
+}
+
+template <>
+void ParallelRDP::UpdateScreen<false>() const {
   UpdateScreen(static_cast<Util::IntrusivePtr<Image>>(nullptr));
 }
 
-void ParallelRDP::EnqueueCommand(int command_length, const u32 *buffer) const {
+void ParallelRDP::EnqueueCommand(const int command_length, const u32 *buffer) const {
   command_processor->enqueue_command(command_length, buffer);
 }
 
diff --git a/external/parallel-rdp/ParallelRDPWrapper.hpp b/external/parallel-rdp/ParallelRDPWrapper.hpp
index d1f56c2d..50db0330 100644
--- a/external/parallel-rdp/ParallelRDPWrapper.hpp
+++ b/external/parallel-rdp/ParallelRDPWrapper.hpp
@@ -17,11 +17,12 @@ public:
 
   void Init(const std::shared_ptr<Vulkan::WSIPlatform> &,
             const std::shared_ptr<WindowInfo> &, const u8 *);
-  
-  void UpdateScreen(bool = true) const;
+
+  template <bool>
+  void UpdateScreen() const;
   void EnqueueCommand(int, const u32 *) const;
   void OnFullSync() const;
-  bool IsFramerateUnlocked() const;
+  [[nodiscard]] bool IsFramerateUnlocked() const;
   void SetFramerateUnlocked(bool) const;
 
   std::shared_ptr<Vulkan::WSI> wsi;
diff --git a/src/frontend/ImGuiImpl/ProgressIndicators.hpp b/src/frontend/ImGuiImpl/ProgressIndicators.hpp
new file mode 100644
index 00000000..fcd7b747
--- /dev/null
+++ b/src/frontend/ImGuiImpl/ProgressIndicators.hpp
@@ -0,0 +1,43 @@
+#pragma once
+#include <imgui.h>
+#include <imgui_internal.h>
+
+namespace ImGui {
+inline bool Spinner(const char* label, const float radius, const int thickness, const ImU32& color) {
+  ImGuiWindow* window = GetCurrentWindow();
+  if (window->SkipItems)
+    return false;
+
+  const ImGuiContext & g = *GImGui;
+  const ImGuiStyle& style = g.Style;
+  const ImGuiID id = window->GetID(label);
+
+  const ImVec2 pos = window->DC.CursorPos;
+  const ImVec2 size(radius*2, (radius + style.FramePadding.y)*2);
+
+  const ImRect bb(pos, ImVec2(pos.x + size.x, pos.y + size.y));
+  ItemSize(bb, style.FramePadding.y);
+  if (!ItemAdd(bb, id))
+    return false;
+
+  // Render
+  window->DrawList->PathClear();
+
+  constexpr int num_segments = 30;
+  const int start = abs(ImSin(g.Time*1.8f)*(num_segments-5));
+
+  const float a_min = IM_PI * 2.0f * static_cast<float>(start) / static_cast<float>(num_segments);
+  constexpr float a_max = IM_PI*2.0f * (static_cast<float>(num_segments) -3) / static_cast<float>(num_segments);
+
+  const auto centre = ImVec2(pos.x+radius, pos.y+radius+style.FramePadding.y);
+
+  for (int i = 0; i < num_segments; i++) {
+    const float a = a_min + static_cast<float>(i) / static_cast<float>(num_segments) * (a_max - a_min);
+    window->DrawList->PathLineTo(ImVec2(centre.x + ImCos(a+g.Time*8) * radius,
+                                        centre.y + ImSin(a+g.Time*8) * radius));
+  }
+
+  window->DrawList->PathStroke(color, false, thickness);
+  return true;
+}
+}
\ No newline at end of file
diff --git a/src/frontend/ImGuiImpl/StatusBar.hpp b/src/frontend/ImGuiImpl/StatusBar.hpp
index bbb9c76d..0a3dbf3d 100644
--- a/src/frontend/ImGuiImpl/StatusBar.hpp
+++ b/src/frontend/ImGuiImpl/StatusBar.hpp
@@ -1,7 +1,6 @@
 #pragma once
 #include <imgui.h>
 #include <imgui_internal.h>
-#include <functional>
 
 namespace ImGui {
 inline bool BeginMainStatusBar()
diff --git a/src/frontend/KaizenGui.cpp b/src/frontend/KaizenGui.cpp
index 52ece1a8..969e545e 100644
--- a/src/frontend/KaizenGui.cpp
+++ b/src/frontend/KaizenGui.cpp
@@ -1,6 +1,7 @@
 #include <KaizenGui.hpp>
 #include <backend/Core.hpp>
 #include <ImGuiImpl/GUI.hpp>
+#include <ImGuiImpl/ProgressIndicators.hpp>
 #include <ImGuiImpl/StatusBar.hpp>
 #include <resources/gamecontrollerdb.h>
 
@@ -9,6 +10,10 @@ KaizenGui::KaizenGui() noexcept : window("Kaizen", 800, 600), settingsWindow(win
   SDL_InitSubSystem(SDL_INIT_GAMEPAD);
 
   SDL_AddGamepadMapping(gamecontrollerdb_str);
+
+  std::thread fileWorker(&KaizenGui::FileWorker, this);
+
+  fileWorker.detach();
 }
 
 KaizenGui::~KaizenGui() {
@@ -16,7 +21,7 @@ KaizenGui::~KaizenGui() {
   SDL_Quit();
 }
 
-void KaizenGui::QueryDevices(SDL_Event event) {
+void KaizenGui::QueryDevices(const SDL_Event &event) {
   switch (event.type) {
   case SDL_EVENT_GAMEPAD_ADDED:
     if (!gamepad) {
@@ -36,8 +41,8 @@ void KaizenGui::QueryDevices(SDL_Event event) {
   }
 }
 
-void KaizenGui::HandleInput(SDL_Event event) {
-  n64::Core& core = n64::Core::GetInstance();
+void KaizenGui::HandleInput(const SDL_Event &event) {
+  const n64::Core& core = n64::Core::GetInstance();
   n64::PIF &pif = n64::Core::GetMem().mmio.si.pif;
   switch(event.type) {
     case SDL_EVENT_GAMEPAD_AXIS_MOTION:
@@ -52,7 +57,7 @@ void KaizenGui::HandleInput(SDL_Event event) {
 
         float xclamped = SDL_GetGamepadAxis(gamepad, SDL_GAMEPAD_AXIS_LEFTX);
         if (xclamped < 0) {
-          xclamped /= float(std::abs(SDL_JOYSTICK_AXIS_MAX));
+          xclamped /= static_cast<float>(std::abs(SDL_JOYSTICK_AXIS_MAX));
         } else {
           xclamped /= SDL_JOYSTICK_AXIS_MAX;
         }
@@ -61,15 +66,15 @@ void KaizenGui::HandleInput(SDL_Event event) {
 
         float yclamped = SDL_GetGamepadAxis(gamepad, SDL_GAMEPAD_AXIS_LEFTY);
         if (yclamped < 0) {
-          yclamped /= float(std::abs(SDL_JOYSTICK_AXIS_MIN));
+          yclamped /= static_cast<float>(std::abs(SDL_JOYSTICK_AXIS_MIN));
         } else {
           yclamped /= SDL_JOYSTICK_AXIS_MAX;
         }
 
         yclamped *= 86;
 
-        pif.UpdateAxis(0, n64::Controller::Axis::Y, -yclamped);
-        pif.UpdateAxis(0, n64::Controller::Axis::X, xclamped);
+        pif.UpdateAxis(0, n64::Controller::Axis::Y, static_cast<s8>(-yclamped));
+        pif.UpdateAxis(0, n64::Controller::Axis::X, static_cast<s8>( xclamped));
       }
       break;
     case SDL_EVENT_GAMEPAD_BUTTON_DOWN:
@@ -90,7 +95,7 @@ void KaizenGui::HandleInput(SDL_Event event) {
     case SDL_EVENT_KEY_DOWN:
     case SDL_EVENT_KEY_UP:
       {
-        auto keys = SDL_GetKeyboardState(nullptr);
+        const auto keys = SDL_GetKeyboardState(nullptr);
         if((keys[SDL_SCANCODE_LCTRL] || keys[SDL_SCANCODE_RCTRL]) && keys[SDL_SCANCODE_O]) {
           fileDialogOpen = true;
         }
@@ -130,15 +135,25 @@ void KaizenGui::HandleInput(SDL_Event event) {
         pif.UpdateButton(0, n64::Controller::Key::DRight, keys[SDL_SCANCODE_L]);
         pif.UpdateButton(0, n64::Controller::Key::LT, keys[SDL_SCANCODE_A]);
         pif.UpdateButton(0, n64::Controller::Key::RT, keys[SDL_SCANCODE_S]);
-        pif.UpdateAxis(0, n64::Controller::Axis::Y, keys[SDL_SCANCODE_UP] ? 86 : keys[SDL_SCANCODE_DOWN] ? -86 : 0);
-        pif.UpdateAxis(0, n64::Controller::Axis::X, keys[SDL_SCANCODE_LEFT] ? -86 : keys[SDL_SCANCODE_RIGHT] ? 86 : 0);
+
+        if (keys[SDL_SCANCODE_UP]) pif.UpdateAxis(0, n64::Controller::Axis::Y, 86);
+        else pif.UpdateAxis(0, n64::Controller::Axis::Y, 0);
+
+        if (keys[SDL_SCANCODE_DOWN]) pif.UpdateAxis(0, n64::Controller::Axis::Y, -86);
+        else pif.UpdateAxis(0, n64::Controller::Axis::Y, 0);
+
+        if (keys[SDL_SCANCODE_LEFT]) pif.UpdateAxis(0, n64::Controller::Axis::X, -86);
+        else pif.UpdateAxis(0, n64::Controller::Axis::X, 0);
+
+        if (keys[SDL_SCANCODE_RIGHT]) pif.UpdateAxis(0, n64::Controller::Axis::X, 86);
+        else pif.UpdateAxis(0, n64::Controller::Axis::X, 0);
       }
       break;
     default: break;
   }
 }
 
-std::tuple<std::optional<u64>, std::optional<Util::Error::MemoryAccess>> RenderErrorMessageDetails() {
+std::pair<std::optional<s64>, std::optional<Util::Error::MemoryAccess>> RenderErrorMessageDetails() {
   auto lastPC = Util::Error::GetLastPC();
   if(lastPC.has_value()) {
     ImGui::Text("%s", std::format("Occurred @ PC = {:016X}", Util::Error::GetLastPC().value()).c_str());
@@ -146,10 +161,10 @@ std::tuple<std::optional<u64>, std::optional<Util::Error::MemoryAccess>> RenderE
 
   auto memoryAccess = Util::Error::GetMemoryAccess();
   if(memoryAccess.has_value()) {
-    auto memoryAccessV = memoryAccess.value();
-    ImGui::Text("%s", std::format("{} {}-bit value @ {:08X}{}", memoryAccessV.is_write ? "Writing" : "Reading",
-                                  (u8)memoryAccessV.size, memoryAccessV.address,
-                                  memoryAccessV.is_write ? std::format(" (value = 0x{:X})", memoryAccessV.written_val) : "")
+    const auto [is_write, size, address, written_val] = memoryAccess.value();
+    ImGui::Text("%s", std::format("{} {}-bit value @ {:08X}{}", is_write ? "Writing" : "Reading",
+                                  static_cast<u8>(size), address,
+                                  is_write ? std::format(" (value = 0x{:X})", written_val) : "")
                                   .c_str());
   }
 
@@ -227,7 +242,7 @@ void KaizenGui::RenderUI() {
   settingsWindow.render();
   debugger.render();
 
-  ImVec2 center = ImGui::GetMainViewport()->GetCenter();
+  const ImVec2 center = ImGui::GetMainViewport()->GetCenter();
   ImGui::SetNextWindowPos(center, ImGuiCond_Appearing, ImVec2(0.5f, 0.5f));
 
   if (ImGui::BeginPopupModal("About Kaizen", &aboutOpen, ImGuiWindowFlags_AlwaysAutoResize)) {
@@ -258,9 +273,9 @@ void KaizenGui::RenderUI() {
         RenderErrorMessageDetails();
 
         if(n64::Core::GetInstance().romLoaded && !n64::Core::GetInstance().pause) {
-          bool ignore = ImGui::Button("Try continuing"); ImGui::SameLine();
-          bool stop = ImGui::Button("Stop emulation"); ImGui::SameLine();
-          bool chooseAnother = ImGui::Button("Choose another ROM");
+          const bool ignore = ImGui::Button("Try continuing"); ImGui::SameLine();
+          const bool stop = ImGui::Button("Stop emulation"); ImGui::SameLine();
+          const bool chooseAnother = ImGui::Button("Choose another ROM");
           if(ignore || stop || chooseAnother) {
             Util::Error::SetHandled();
             ImGui::CloseCurrentPopup();
@@ -306,10 +321,10 @@ void KaizenGui::RenderUI() {
         ImGui::Text(R"(Error message: "%s")", Util::Error::GetError().c_str());
         auto [lastPC, memoryAccess] = RenderErrorMessageDetails();
 
-        bool ignore = ImGui::Button("Try continuing"); ImGui::SameLine();
-        bool stop = ImGui::Button("Stop emulation"); ImGui::SameLine();
-        bool chooseAnother = ImGui::Button("Choose another ROM");
-        bool openInDebugger = lastPC.has_value() ? ImGui::Button("Add breakpoint at this PC and open the debugger") : false;
+        const bool ignore = ImGui::Button("Try continuing"); ImGui::SameLine();
+        const bool stop = ImGui::Button("Stop emulation"); ImGui::SameLine();
+        const bool chooseAnother = ImGui::Button("Choose another ROM");
+        const bool openInDebugger = lastPC.has_value() ? ImGui::Button("Add breakpoint at this PC and open the debugger") : false;
         if(ignore || stop || chooseAnother || openInDebugger) {
           Util::Error::SetHandled();
           ImGui::CloseCurrentPopup();
@@ -346,6 +361,26 @@ void KaizenGui::RenderUI() {
     ImGui::EndMainStatusBar();
   }
 
+  if (shouldDisplaySpinner) {
+    ImGui::SetNextWindowPos({static_cast<float>(width) * 0.5f, static_cast<float>(height) * 0.5f}, 0, ImVec2(0.5f, 0.5f));
+    ImGui::PushStyleColor(ImGuiCol_WindowBg, IM_COL32_BLACK_TRANS);
+    ImGui::PushStyleVar(ImGuiStyleVar_WindowBorderSize, 0.0f);
+
+    ImGui::Begin("##spinnerContainer", nullptr, ImGuiWindowFlags_AlwaysAutoResize | ImGuiWindowFlags_NoDecoration);
+
+    ImGui::Spinner("##spinner", 10.f, 4.f, ImGui::GetColorU32(ImGui::GetStyle().Colors[ImGuiCol_TitleBgActive]));
+    ImGui::SameLine();
+
+    ImGui::PushFont(nullptr, ImGui::GetStyle().FontSizeBase * 2.f);
+    ImGui::Text("Loading \"%s\"...", fs::path(fileToLoad).stem().c_str());
+    ImGui::PopFont();
+
+    ImGui::End();
+
+    ImGui::PopStyleVar();
+    ImGui::PopStyleColor();
+  }
+
   ImGui::Render();
   if (ImGui::GetIO().ConfigFlags & ImGuiConfigFlags_ViewportsEnable) {
     ImGui::UpdatePlatformWindows();
@@ -354,20 +389,22 @@ void KaizenGui::RenderUI() {
 
   if(fileDialogOpen) {
     fileDialogOpen = false;
-    const SDL_DialogFileFilter filters[] = {{"All files", "*"}, {"Nintendo 64 executable", "n64;z64;v64"}, {"Nintendo 64 executable archive", "rar;tar;zip;7z"}};
-    SDL_ShowOpenFileDialog([](void *userdata, const char * const *filelist, int filter) {
-      auto kaizen = (KaizenGui*)userdata;
+    constexpr SDL_DialogFileFilter filters[] = {{"All files", "*"}, {"Nintendo 64 executable", "n64;z64;v64"}, {"Nintendo 64 executable archive", "rar;tar;zip;7z"}};
+    SDL_ShowOpenFileDialog([](void *userdata, const char * const *filelist, int) {
+      const auto kaizen = static_cast<KaizenGui*>(userdata);
       
       if (!filelist) {
         panic("An error occured: {}", SDL_GetError());
-        return;
-      } else if (!*filelist) {
+      }
+
+      if (!*filelist) {
         warn("The user did not select any file.");
         warn("Most likely, the dialog was canceled.");
         return;
       }
 
-      kaizen->LoadROM(*filelist);
+      kaizen->fileToLoad = *filelist;
+      kaizen->shouldDisplaySpinner = true;
     }, this, window.getHandle(), filters, 3, nullptr, false);
   }
 
@@ -375,17 +412,17 @@ void KaizenGui::RenderUI() {
     return;
 
   if(core.romLoaded) {
-    core.parallel.UpdateScreen();
+    core.parallel.UpdateScreen<true>();
     return;
   }
 
-  core.parallel.UpdateScreen(false);
+  core.parallel.UpdateScreen<false>();
 }
 
 void KaizenGui::LoadROM(const std::string &path) noexcept {
   n64::Core& core = n64::Core::GetInstance();
   core.LoadROM(path);
-  const auto gameNameDB = core.GetMem().rom.gameNameDB;
+  const auto gameNameDB = n64::Core::GetMem().rom.gameNameDB;
   SDL_SetWindowTitle(window.getHandle(), ("Kaizen - " + gameNameDB).c_str());
 }
 
@@ -405,11 +442,14 @@ void KaizenGui::run() {
         case SDL_EVENT_WINDOW_RESTORED:
           minimized = false;
           break;
+        default:
       }
       QueryDevices(e);
       HandleInput(e);
     }
 
+    SDL_GetWindowSize(window.getHandle(), &width, &height);
+
     emuThread.run();
     RenderUI();
   }
diff --git a/src/frontend/KaizenGui.hpp b/src/frontend/KaizenGui.hpp
index a884ac8b..7e9f1c05 100644
--- a/src/frontend/KaizenGui.hpp
+++ b/src/frontend/KaizenGui.hpp
@@ -27,10 +27,23 @@ public:
   static void LoadTAS(const std::string &path) noexcept;
   void LoadROM(const std::string &path) noexcept;
 private:
+  int width{}, height{};
   bool aboutOpen = false;
   bool fileDialogOpen = false;
   bool quit = false;
+  bool shouldDisplaySpinner = false;
+  std::string fileToLoad;
   void RenderUI();
-  void HandleInput(SDL_Event event);
-  void QueryDevices(SDL_Event event);
+  void HandleInput(const SDL_Event &event);
+  void QueryDevices(const SDL_Event &event);
+
+  [[noreturn]] void FileWorker() {
+    while (true) {
+      if (!fileToLoad.empty()) {
+        LoadROM(fileToLoad);
+        shouldDisplaySpinner = false;
+        fileToLoad = "";
+      }
+    }
+  }
 };
diff --git a/src/frontend/main.cpp b/src/frontend/main.cpp
index 533e6bfa..65833999 100644
--- a/src/frontend/main.cpp
+++ b/src/frontend/main.cpp
@@ -1,7 +1,7 @@
 #include <KaizenGui.hpp>
 #include <cflags.hpp>
 
-int main(int argc, char **argv) {
+int main(const int argc, char **argv) {
   KaizenGui kaizenGui; 
   cflags::cflags flags;
   flags.add_string_callback('\0', "rom", [&kaizenGui](const std::string& v) { kaizenGui.LoadROM(v); }, "Rom to launch from command-line");
diff --git a/src/utils/ErrorData.hpp b/src/utils/ErrorData.hpp
index 54529b39..43de5032 100644
--- a/src/utils/ErrorData.hpp
+++ b/src/utils/ErrorData.hpp
@@ -14,7 +14,7 @@ struct Error {
             UNRECOVERABLE,
         } as_enum;
 
-        const char* as_c_str() {
+        [[nodiscard]] const char* as_c_str() const {
             switch(as_enum) {
                 case NONE: return "";
                 case WARN: return "Warning";
@@ -70,7 +70,7 @@ struct Error {
         } as_enum;
 
         
-        const char* as_c_str() {
+        [[nodiscard]] const char* as_c_str() const {
             switch(as_enum) {
                 case SCHEDULER_EOL: return "SCHEDULER_EOL";
                 case SCHEDULER_UNKNOWN: return "SCHEDULER_UNKNOWN";
@@ -108,11 +108,9 @@ struct Error {
     };
 
     template <class... Args>
-    void Throw (Severity severity,
-                Type type,
-                std::optional<u64> lastPC,
-                std::optional<MemoryAccess> memoryAccess,
-                const std::format_string<Args...> fmt, Args... args) {
+    void Throw (const Severity severity, const Type type, const std::optional<u64> lastPC,
+               const std::optional<MemoryAccess> memoryAccess,
+               const std::format_string<Args...> fmt, Args... args) {
         this->severity = severity;
         this->lastPC = lastPC;
         this->memoryAccess = memoryAccess;
@@ -128,7 +126,7 @@ struct Error {
     static std::string& GetError() { return GetInstance().err; }
     static Severity& GetSeverity() { return GetInstance().severity; }
     static Type& GetType() { return GetInstance().type; }
-    static std::optional<u64>& GetLastPC() { return GetInstance().lastPC; }
+    static std::optional<s64>& GetLastPC() { return GetInstance().lastPC; }
     static std::optional<MemoryAccess>& GetMemoryAccess() { return GetInstance().memoryAccess; }
     static bool IsHandled() {
         return GetSeverity().as_enum == Severity::NONE;
@@ -145,7 +143,7 @@ private:
     std::string err;
     Severity severity = {};
     Type type = {};
-    std::optional<u64> lastPC = {};
+    std::optional<s64> lastPC = {};
     std::optional<MemoryAccess> memoryAccess = {};
 };
 }
\ No newline at end of file