diff --git a/dbc.hpp b/dbc.hpp
index a964b75..759793b 100644
--- a/dbc.hpp
+++ b/dbc.hpp
@@ -1,3 +1,5 @@
+#pragma once
+
 #include <string>
 #include <fmt/core.h>
 #include <functional>
diff --git a/escape_turings_tarpit.cpp b/escape_turings_tarpit.cpp
index 32cf91f..5bcf2ad 100644
--- a/escape_turings_tarpit.cpp
+++ b/escape_turings_tarpit.cpp
@@ -1,4 +1,5 @@
 #include "dbc.hpp"
+#include "gui.hpp"
 #include "game_engine.hpp"
 #include <chrono>                     // for milliseconds
 #include <efsw/efsw.hpp>
@@ -35,14 +36,8 @@ namespace fs = std::filesystem;
 
 const auto ERROR = fmt::emphasis::bold | fg(fmt::color::red);
 
-vector<string> lines;
-
 #define BUF_MAX 1024
 
-void output(const string &msg) {
-  lines.push_back(msg);
-}
-
 class UpdateListener : public efsw::FileWatchListener {
   public:
     bool changes = false;
@@ -131,88 +126,6 @@ void run_build(GameEngine &game, const char* command) {
 }
 
 
-ButtonOption Style() {
-  auto option = ButtonOption::Animated();
-  option.transform = [](const EntryState& s) {
-    auto element = paragraph(s.label);
-    if (s.focused) {
-      element |= bold;
-    }
-    return element | center | borderEmpty | flex;
-  };
-  return option;
-}
-
-int main_loop(UpdateListener* listener, efsw::FileWatcher* fileWatcher, GameEngine &game, const char *build_cmd) {
-  auto screen = ScreenInteractive::Fullscreen();
-  screen.TrackMouse(true);
-
-  // Create a component counting the number of frames drawn and event handled.
-  float scroll_x = 0.1;
-  float scroll_y = 1.0;
-
-  auto status = Renderer([&] {
-      return vbox({
-        paragraph(fmt::format("HP {}", game.hit_points)),
-        separator(),
-        hbox({
-            text("HP"),
-            gauge(game.hit_points / 100.0f),
-          }),
-      });
-  });
-
-  auto content = Renderer([&] {
-      vector<Element> output;
-
-      for(const auto line : lines) {
-        output.push_back(text(line));
-      }
-
-      return vbox(output);
-    });
-
-  auto scrollable_content = Renderer(content,
-      [&, content] {
-      return content->Render()
-        | focusPositionRelative(scroll_x, scroll_y)
-        | frame | flex;
-  });
-
-  auto component = Renderer(scrollable_content, [&] {
-    return vbox({
-        status->Render(),
-        separator(),
-        scrollable_content->Render() | vscroll_indicator | yframe | size(HEIGHT, LESS_THAN, 20),
-        }) |
-    border;
-  });
-
-  component |= CatchEvent([&](Event) -> bool {
-    return false;
-  });
-
-  Loop loop(&screen, component);
-
-  while (!loop.HasQuitted()) {
-    fileWatcher->watch();
-
-    if(listener->changes) {
-      std::this_thread::sleep_for(std::chrono::milliseconds(1000));
-      output(format("CHANGES! Running build {}", build_cmd));
-      run_build(game, build_cmd);
-      listener->reset_state();
-    }
-
-    loop.RunOnce();
-    screen.Post(Event::Custom);
-    std::this_thread::sleep_for(std::chrono::milliseconds(10));
-  }
-
-  return EXIT_SUCCESS;
-}
-
-
 int main(int argc, char *argv[])
 {
   git_repository* repo = nullptr;
@@ -239,7 +152,18 @@ int main(int argc, char *argv[])
 
     GameEngine game{100};
 
-    int rc = main_loop(listener, fileWatcher, game, build_cmd);
+    int rc = main_loop(game, [&] {
+      fileWatcher->watch();
+
+      if(listener->changes) {
+        std::this_thread::sleep_for(std::chrono::milliseconds(1000));
+        output(format("CHANGES! Running build {}", build_cmd));
+        run_build(game, build_cmd);
+        listener->reset_state();
+      }
+      return 0;
+    });
+
     dbc::check(rc == 0, "Invalid return from main_loop.");
 
     git_libgit2_shutdown();
diff --git a/game_engine.hpp b/game_engine.hpp
index abbf3d4..1311c0f 100644
--- a/game_engine.hpp
+++ b/game_engine.hpp
@@ -1,3 +1,5 @@
+#pragma once
+
 #include <string>
 #include <map>
 #include <vector>
diff --git a/gui.cpp b/gui.cpp
new file mode 100644
index 0000000..7faa860
--- /dev/null
+++ b/gui.cpp
@@ -0,0 +1,99 @@
+#include "gui.hpp"
+#include <stdlib.h>                   // for EXIT_SUCCESS
+#include <chrono>                     // for milliseconds
+#include <fmt/core.h>
+#include <ftxui/component/event.hpp>  // for Event
+#include <ftxui/component/mouse.hpp>  // for ftxui
+#include <ftxui/dom/elements.hpp>  // for text, separator, Element, operator|, vbox, border
+#include <memory>                  // for allocator, shared_ptr
+#include <string>                  // for operator+, to_string
+#include <thread>                  // for sleep_for
+
+#include "ftxui/component/component.hpp"  // for CatchEvent, Renderer, operator|=
+#include "ftxui/component/loop.hpp"       // for Loop
+#include "ftxui/component/screen_interactive.hpp"  // for ScreenInteractive
+#include <vector>
+
+using namespace ftxui;
+using namespace std;
+using namespace fmt;
+namespace fs = std::filesystem;
+
+vector<string> lines;
+
+void output(const string &msg) {
+  lines.push_back(msg);
+}
+
+ButtonOption Style() {
+  auto option = ButtonOption::Animated();
+  option.transform = [](const EntryState& s) {
+    auto element = paragraph(s.label);
+    if (s.focused) {
+      element |= bold;
+    }
+    return element | center | borderEmpty | flex;
+  };
+  return option;
+}
+
+int main_loop(GameEngine &game, std::function<bool()> runner) {
+  auto screen = ScreenInteractive::Fullscreen();
+  screen.TrackMouse(true);
+
+  // Create a component counting the number of frames drawn and event handled.
+  float scroll_x = 0.1;
+  float scroll_y = 1.0;
+
+  auto status = Renderer([&] {
+      return vbox({
+        paragraph(fmt::format("HP {}", game.hit_points)),
+        separator(),
+        hbox({
+            text("HP"),
+            gauge(game.hit_points / 100.0f),
+          }),
+      });
+  });
+
+  auto content = Renderer([&] {
+      vector<Element> output;
+
+      for(const auto line : lines) {
+        output.push_back(text(line));
+      }
+
+      return vbox(output);
+    });
+
+  auto scrollable_content = Renderer(content,
+      [&, content] {
+      return content->Render()
+        | focusPositionRelative(scroll_x, scroll_y)
+        | frame | flex;
+  });
+
+  auto component = Renderer(scrollable_content, [&] {
+    return vbox({
+        status->Render(),
+        separator(),
+        scrollable_content->Render() | vscroll_indicator | yframe | size(HEIGHT, LESS_THAN, 20),
+        }) |
+    border;
+  });
+
+  component |= CatchEvent([&](Event) -> bool {
+    return false;
+  });
+
+  Loop loop(&screen, component);
+
+  while (!loop.HasQuitted()) {
+    int run_error = runner();
+    loop.RunOnce();
+    screen.Post(Event::Custom);
+    std::this_thread::sleep_for(std::chrono::milliseconds(10));
+  }
+
+  return EXIT_SUCCESS;
+}
diff --git a/gui.hpp b/gui.hpp
new file mode 100644
index 0000000..e29d1b0
--- /dev/null
+++ b/gui.hpp
@@ -0,0 +1,10 @@
+#pragma once
+
+#include <efsw/efsw.hpp>
+#include "game_engine.hpp"
+#include <filesystem>
+#include <string>
+
+void output(const string &msg);
+
+int main_loop(GameEngine &game, std::function<bool()> runner);
diff --git a/meson.build b/meson.build
index 73e5c78..da24eeb 100644
--- a/meson.build
+++ b/meson.build
@@ -29,6 +29,7 @@ dependencies = [
 
 executable('escape_turings_tarpit',
   ['game_engine.cpp',
+    'gui.cpp',
     'escape_turings_tarpit.cpp'],
   dependencies: dependencies)