diff --git a/src/engine/controller/controller.hh b/src/engine/controller/controller.hh
index 85979ac..f6a1f3e 100644
--- a/src/engine/controller/controller.hh
+++ b/src/engine/controller/controller.hh
@@ -14,12 +14,12 @@ class Controller {
 	};
 	virtual bool InitializeController() { return false; };
 	virtual void PollController(){};
-	virtual bool IsButtonPressed(Button button) { return 0; };
-	virtual float GetLeftJoystickXAxis() { return 0.0; };
-	virtual float GetLeftJoystickYAxis() { return 0.0; };
+	virtual bool IsButtonPressed(Button button) const { return 0; };
+	virtual float GetLeftJoystickXAxis() const { return 0.0; };
+	virtual float GetLeftJoystickYAxis() const { return 0.0; };
 	virtual ~Controller() {};
 
    protected:
-	virtual int GetButtonMask(Button button) { return 0; }
+	virtual int GetButtonMask(Button button) const { return 0; }
 };
 #endif
diff --git a/src/engine/controller/desktopController.cc b/src/engine/controller/desktopController.cc
index 9c34061..7db0689 100644
--- a/src/engine/controller/desktopController.cc
+++ b/src/engine/controller/desktopController.cc
@@ -24,19 +24,19 @@ void DesktopController::PollController() {
 	glfwGetGamepadState(GLFW_JOYSTICK_1, &controllerState);
 }
 
-bool DesktopController::IsButtonPressed(Button button) {
+bool DesktopController::IsButtonPressed(Button button) const {
 	return controllerState.buttons[GetButtonMask(button)];
 }
 
-float DesktopController::GetLeftJoystickXAxis() {
+float DesktopController::GetLeftJoystickXAxis() const {
 	return controllerState.axes[GLFW_GAMEPAD_AXIS_LEFT_X];
 }
 
-float DesktopController::GetLeftJoystickYAxis() {
+float DesktopController::GetLeftJoystickYAxis() const {
 	return controllerState.axes[GLFW_GAMEPAD_AXIS_LEFT_Y];
 }
 
-int DesktopController::GetButtonMask(Button button) {
+int DesktopController::GetButtonMask(Button button) const {
 	switch (button) {
 		case Button::A:
 			return GLFW_GAMEPAD_BUTTON_A;
diff --git a/src/engine/controller/desktopController.hh b/src/engine/controller/desktopController.hh
index 2678cef..8ecc6ea 100644
--- a/src/engine/controller/desktopController.hh
+++ b/src/engine/controller/desktopController.hh
@@ -7,10 +7,10 @@ class DesktopController : public Controller {
 	public:
 	bool InitializeController() override;
 	void PollController() override;
-	bool IsButtonPressed(Button button) override;
-	float GetLeftJoystickXAxis() override;
-	float GetLeftJoystickYAxis() override;
-	int GetButtonMask(Button button) override;
+	bool IsButtonPressed(Button button) const override;
+	float GetLeftJoystickXAxis() const override;
+	float GetLeftJoystickYAxis() const override;
+	int GetButtonMask(Button button) const override;
 	GLFWgamepadstate controllerState;
 };
 
diff --git a/src/engine/controller/dreamcastController.cc b/src/engine/controller/dreamcastController.cc
index a710200..734467f 100644
--- a/src/engine/controller/dreamcastController.cc
+++ b/src/engine/controller/dreamcastController.cc
@@ -21,19 +21,19 @@ void DreamcastController::PollController() {
 	controller_state = (cont_state_t*)maple_dev_status(controller);
 }
 
-bool DreamcastController::IsButtonPressed(Button button) {
+bool DreamcastController::IsButtonPressed(Button button) const {
 	return controller_state->buttons & GetButtonMask(button);
 }
 
-float DreamcastController::GetLeftJoystickXAxis() {
+float DreamcastController::GetLeftJoystickXAxis() const {
 	return (controller_state->joyx / 127.0f);
 }
 
-float DreamcastController::GetLeftJoystickYAxis() {
+float DreamcastController::GetLeftJoystickYAxis() const {
 	return (controller_state->joyy / 127.0f);
 }
 
-int DreamcastController::GetButtonMask(Button button) {
+int DreamcastController::GetButtonMask(Button button) const {
 	switch (button) {
 		case Button::A:
 			return CONT_A;
diff --git a/src/engine/controller/dreamcastController.hh b/src/engine/controller/dreamcastController.hh
index e8c47a0..1e02498 100644
--- a/src/engine/controller/dreamcastController.hh
+++ b/src/engine/controller/dreamcastController.hh
@@ -8,10 +8,10 @@ class DreamcastController : public Controller {
 	DreamcastController();
 	bool InitializeController() override;
 	void PollController() override;
-	bool IsButtonPressed(Button button) override;
-	float GetLeftJoystickXAxis() override;
-	float GetLeftJoystickYAxis() override;
-	int GetButtonMask(Button button) override;
+	bool IsButtonPressed(Button button) const override;
+	float GetLeftJoystickXAxis() const override;
+	float GetLeftJoystickYAxis() const override;
+	int GetButtonMask(Button button) const override;
 	maple_device_t* controller = nullptr;
 	cont_state_t* controller_state = nullptr;
 };
diff --git a/src/engine/engine.cc b/src/engine/engine.cc
index 6e89bbd..ac5021f 100644
--- a/src/engine/engine.cc
+++ b/src/engine/engine.cc
@@ -68,6 +68,7 @@ void Engine::deltaTimeLoop(T&& callback, struct timeval& beginningOfFrame,
 void Engine::initializeGameLoop() {
 	struct timeval beginningOfFrame, endOfFrame;
 
+	start();
 	while (!ShouldWindowClose()) {
 		deltaTimeLoop(&Engine::gameLoop, beginningOfFrame, endOfFrame);
 	}
diff --git a/src/engine/engine.hh b/src/engine/engine.hh
index 2caa9a5..db90971 100644
--- a/src/engine/engine.hh
+++ b/src/engine/engine.hh
@@ -28,6 +28,7 @@ class Engine {
 
 	virtual void initScreen();
 	virtual void gameLoop(){};
+	virtual void start() {};
 	void printSystemInformation();
 	void SwapBuffers() const;
 	bool ShouldWindowClose() const;
diff --git a/src/engine/entity.hh b/src/engine/entity.hh
index 8b9faa8..800fd57 100644
--- a/src/engine/entity.hh
+++ b/src/engine/entity.hh
@@ -22,12 +22,12 @@ class Entity {
 	void updatePosition(Engine::Vector3 position);
 	Engine::Vector3 getScale() const;
 	void updateScale(Engine::Vector3 scale);
+	void DestroyChildren();
 
    private:
 	Engine::Vector3 position = Engine::Vector3::zero;
 	Engine::Vector3 globalPosition = Engine::Vector3::zero;
 	Engine::Vector3 scale = {1, 1, 1};
-	void DestroyChildren();
 	static void drawChildrenEntity(Entity* entity);
 	static void updateChildrenEntity(Entity* entity);
 };
diff --git a/src/engine/meson.build b/src/engine/meson.build
index 7d62a40..e66f4f3 100644
--- a/src/engine/meson.build
+++ b/src/engine/meson.build
@@ -10,5 +10,17 @@ endif
 
 subdir('controller')
 
-engine = static_library('engine', ['dreamcastEngine.cc', 'desktopEngine.cc', 'entity.cc', 'engine.cc'], dependencies: engine_deps, include_directories: incdirs)
+engine_src = []
+
+if host_machine.system() == 'dreamcast'
+	engine_src += 'dreamcastEngine.cc'
+endif
+
+if host_machine.system() != 'dreamcast'
+	engine_src += 'desktopEngine.cc'
+endif
+
+engine_src += ['entity.cc', 'engine.cc']
+
+engine = static_library('engine', engine_src, dependencies: engine_deps, include_directories: incdirs)
 engine_dep = declare_dependency(link_with: [engine, controller], include_directories: incdirs)
diff --git a/src/flappyBird/Bird.cc b/src/flappyBird/Bird.cc
index 49aa1fc..1197e80 100644
--- a/src/flappyBird/Bird.cc
+++ b/src/flappyBird/Bird.cc
@@ -21,7 +21,7 @@ void Bird::draw() {
 
 void Bird::update() {
 	if (pipes != nullptr) {
-		for (int i = 0; i < pipes->children.size(); i++) {
+		for (size_t i = 0; i < pipes->children.size(); i++) {
 			if (getGlobalPosition().x >=
 					pipes->children[i]->getGlobalPosition().x - 0.1f &&
 				getGlobalPosition().x <=
diff --git a/src/flappyBird/FlappyBird.cc b/src/flappyBird/FlappyBird.cc
index 5e35ca9..2b3a303 100644
--- a/src/flappyBird/FlappyBird.cc
+++ b/src/flappyBird/FlappyBird.cc
@@ -1,5 +1,7 @@
 #include "FlappyBird.hh"
 
+#include <chrono>
+#include <mutex>
 #include <thread>
 
 #include "MainMenu.hh"
@@ -10,19 +12,21 @@ void FlappyBird::gameLoop() {
 		return;
 	}
 
+	if (!thread) {
+		thread = new std::thread(&FlappyBird::spawnPipes, this);
+	}
+
 	mainGameLoop();
 }
 
 void FlappyBird::spawnPipes() {
 	threadRunning = true;
 	while (threadRunning) {
-		addNewPipe = true;
-		while (addNewPipe) {
-			if (!threadRunning) {
-				return;
-			}
-			std::this_thread::yield();
-		}
+		doneSpawningPipes = false;
+		pipesContainer->children.push_back(
+			Pipes::CreatePipes(this, pipesContainer));
+		doneSpawningPipes = true;
+		cv.notify_one();
 		std::this_thread::sleep_for(std::chrono::seconds(2));
 	}
 }
@@ -34,21 +38,18 @@ void FlappyBird::mainGameLoop() {
 		SwapBuffers();
 		return;
 	}
-	if (!thread) {
-		thread = new std::thread(&FlappyBird::spawnPipes, this);
-	}
+
 	for (size_t i = 0; i < pipesContainer->children.size(); i++) {
 		if (pipesContainer->children[i]->destroyed) {
-			// delete pipesContainer->children[i];
+			delete pipesContainer->children[i];
 			pipesContainer->children.erase(pipesContainer->children.begin() +
 										   i);
 		}
 	}
-	if (addNewPipe) {
-		pipesContainer->children.push_back(
-			Pipes::CreatePipes(this, pipesContainer));
-		addNewPipe = false;
-	}
+
+	std::unique_lock lock(mutex);
+	cv.wait(lock, [&]{return doneSpawningPipes;});
+	rendering = true;
 	glClear(GL_COLOR_BUFFER_BIT);
 	controller->PollController();
 	Entity::updateEntity(this->bird);
@@ -64,7 +65,10 @@ void FlappyBird::mainMenuLoop() {
 		thread->detach();
 		delete thread;
 		thread = nullptr;
+		pipesContainer->DestroyChildren();
 		pipesContainer->children.clear();
+		SwapBuffers();
+		return;
 	}
 	controller->PollController();
 	Entity::updateEntity(this->mainMenu);
diff --git a/src/flappyBird/FlappyBird.hh b/src/flappyBird/FlappyBird.hh
index 9a569b0..9cd213e 100644
--- a/src/flappyBird/FlappyBird.hh
+++ b/src/flappyBird/FlappyBird.hh
@@ -1,5 +1,7 @@
 #ifndef FLAPPY_BIRD_HH
 #define FLAPPY_BIRD_HH
+#include <condition_variable>
+#include <mutex>
 #include <thread>
 #include <engine/engine.hh>
 #include <engine/entity.hh>
@@ -19,7 +21,10 @@ class FlappyBird : public Engine {
 	MainMenu* mainMenu;
 	std::thread* thread = nullptr;
 	bool threadRunning;
-	bool addNewPipe;
+	bool doneSpawningPipes = true;
+	bool rendering = false;
+	std::mutex mutex;
+	std::condition_variable cv;
 	FlappyBird();
 	~FlappyBird();
 };