diff --git a/src/entry_linux.c b/src/entry_linux.c
index f2c270a..d6b07ec 100644
--- a/src/entry_linux.c
+++ b/src/entry_linux.c
@@ -59,6 +59,13 @@ void RunThreadFunc(pthread_t *th, u32 *u, void *func)
 	pthread_create(th, NULL, func, u);
 }
 
+#define BIL 1000000000L
+
+u64 GetDiff(struct timespec *start, struct timespec *end)
+{
+	return BIL * (end->tv_sec - start->tv_sec) + end->tv_nsec - start->tv_nsec;
+}
+
 int main(int argc, char **argv) 
 {
 	u8 *mem = (u8 *)MemAllocZeroed(MB(64));
diff --git a/src/game.c b/src/game.c
index 92e3674..4e61f43 100644
--- a/src/game.c
+++ b/src/game.c
@@ -8,11 +8,11 @@ static void InitializeGame(Arena *arena, GameContext *ctx, Arena *ctx_arena)
 	ctx->gui.indices_len = 0;
 	ctx->gui.instance_count = 0;
 
-	ctx->window.p0.x = 0.0f;
-	ctx->window.p0.y = 0.0f;
+	ctx->windows = ArenaAlloc(ctx_arena, sizeof(GUIWindow) * 32);
+	ctx->window_len = 0;
 
-	ctx->window.p1.x = 100.0f;
-	ctx->window.p1.y = 100.0f;
+	ctx->buttons = ArenaAlloc(ctx_arena, sizeof(GUIButton) * 64);
+	ctx->btn_len = 0;
 
 	ctx->arena = arena;
 }
@@ -24,6 +24,7 @@ static void DestroyGame()
 
 u32 selected_rect = 0;
 b8 mouse_pressed = false;
+b8 mouse_clicked = false;
 i16 mouse_prev_pos_x = 0;
 i16 mouse_prev_pos_y = 0;
 i16 mouse_pos_x = 0;
@@ -31,6 +32,8 @@ i16 mouse_pos_y = 0;
 
 static void HandleInputs(GameInput *inputs, u32 count)
 {
+	mouse_clicked = false;
+
 	for (u32 i = 0; i < count; i++)
 	{
 		if (inputs[i].type == GI_KEYBOARD)
@@ -59,7 +62,11 @@ static void HandleInputs(GameInput *inputs, u32 count)
 		else if (inputs[i].type == GI_MOUSE)
 		{
 			if (inputs[i].m_code == M_LEFT_CLICK)
+			{
 				mouse_pressed = inputs[i].pressed;
+				if (!inputs[i].pressed)
+					mouse_clicked = true;
+			}
 		}
 		else if (inputs[i].type == GI_MOTION)
 		{
@@ -71,46 +78,188 @@ static void HandleInputs(GameInput *inputs, u32 count)
 	}
 }
 
+static inline void PrepareGUICtx(GameContext *ctx)
+{
+	ctx->gui.has_grabbed = false;
+}
+
+static inline u32 StrToU32(char *str)
+{
+	u32 result = 0;
+	for (; *str != '\0'; str++)
+	{
+		result += (u32)(*str);
+	}
+	return result;
+}
+
+static b32 UIButton(GameContext *ctx, char *label, f32 x0, f32 y0, f32 x1, f32 y1)
+{
+	GUIButton *btn = NULL;
+	u32 id = StrToU32(label) + (u32)(x0 + y0 + x1 + y1);
+	if (ctx->btn_len == 0)
+	{
+		ctx->buttons[0].p0.x = x0;
+		ctx->buttons[0].p0.y = y0;
+		ctx->buttons[0].p1.x = x1;
+		ctx->buttons[0].p1.y = y1;
+		ctx->buttons[0].id = id;
+		ctx->buttons[0].pressed = false;
+		ctx->buttons[0].pressed_prev = false;
+
+		btn = &ctx->buttons[0];
+		ctx->btn_len += 1;
+	}
+	else 
+	{
+		for (u32 i = 0; i < ctx->btn_len; i++)
+		{
+			if (ctx->buttons[i].id == id)
+			{
+				btn = &ctx->buttons[i];
+				break;
+			}
+		}
+
+		if (btn == NULL)
+		{
+			ctx->btn_len += 1;
+			btn = &ctx->buttons[ctx->btn_len];
+
+			btn->p0.x = x0;
+			btn->p0.y = y0;
+			btn->p1.x = x1;
+			btn->p1.y = y1;
+			btn->id = id;
+			btn->pressed = false;
+			btn->pressed_prev = false;
+		}
+	}
+
+	Assert(btn != NULL, "button is null");
+
+	if (mouse_clicked
+		  && !ctx->gui.has_grabbed
+			&& mouse_pos_x > btn->p0.x
+			&& mouse_pos_x < btn->p1.x
+			&& mouse_pos_y > btn->p0.y
+			&& mouse_pos_y < btn->p1.y)
+	{
+		btn->pressed = !btn->pressed;
+	}
+
+	DrawRect(&ctx->gui, btn->p0, btn->p1, (Vec4){ .r = 0.1f, .g = 0.9f, .b = 0.4f, .a = 1.0f });
+
+	return btn->pressed;
+}
+
+static b32 UIWindow(GameContext *ctx, char *title, f32 x0, f32 y0, f32 x1, f32 y1)
+{
+	GUIWindow *win = NULL;
+	u32 id = StrToU32(title) + (u32)(x0 + y0 + x1 + y1);
+	if (ctx->window_len == 0)
+	{
+		ctx->windows[0].p0.x = x0;
+		ctx->windows[0].p0.y = y0;
+		ctx->windows[0].p1.x = x1;
+		ctx->windows[0].p1.y = y1;
+		ctx->windows[0].id = id;
+
+		win = &ctx->windows[0];
+		ctx->window_len += 1;
+	}
+	else 
+	{
+		for (u32 i = 0; i < ctx->window_len; i++)
+		{
+			if (ctx->windows[i].id == id)
+			{
+				win = &ctx->windows[i];
+				break;
+			}
+		}
+
+		if (win == NULL)
+		{
+			ctx->window_len += 1;
+			win = &ctx->windows[ctx->window_len];
+
+			win->p0.x = x0;
+			win->p0.y = y0;
+			win->p1.x = x1;
+			win->p1.y = y1;
+			win->id = id;
+		}
+	}
+
+	Assert(win != NULL, "window is null");
+
+	if (mouse_pressed && !win->grabbed 
+		&& mouse_pos_x > win->p0.x 
+		&& mouse_pos_x < win->p1.x 
+		&& mouse_pos_y > win->p0.y
+		&& mouse_pos_y < win->p1.y
+		&& !ctx->gui.has_grabbed)
+	{
+		win->grabbed = true;
+		ctx->gui.has_grabbed = true;
+
+		win->grabbed_pos.x = (f32)mouse_pos_x - win->p0.x;
+		win->grabbed_pos.y = (f32)mouse_pos_y - win->p0.y;
+	}
+	else if (!mouse_pressed && win->grabbed)
+	{
+		win->grabbed = false;
+
+		win->grabbed_pos.x = 0.0f;
+		win->grabbed_pos.y = 0.0f;
+	}
+
+	if (win->grabbed)
+	{
+		f32 w = win->p1.x - win->p0.x;
+		f32 h = win->p1.y - win->p0.y;
+
+		win->p0.x = (f32)(mouse_pos_x) - win->grabbed_pos.x;
+		win->p0.y = (f32)(mouse_pos_y) - win->grabbed_pos.y;
+		win->p1.x = win->p0.x + w;
+		win->p1.y = win->p0.y + h;
+
+		ctx->gui.has_grabbed = true;
+	}
+
+	DrawRect(&ctx->gui, win->p0, win->p1, (Vec4){ .r = 0.1f, .g = 0.3f, .b = 0.8f, .a = 1.0f });
+
+	return true;
+}
+
 static void RunCycle(GameContext *ctx, GameInput *inputs, u32 i_count)
 {
 	__atomic_store_n(&renderer.vk.imm.job_count, 0, __ATOMIC_RELEASE);
 	__atomic_store_n(&renderer.vk.imm.remaining_count, 0, __ATOMIC_RELEASE);
 
-	GetViewportSize(&ctx->pc.res);
+	PrepareGUICtx(ctx);
 
 	HandleInputs(inputs, i_count);
 
-	if (mouse_pressed && !ctx->window.grabbed 
-		&& mouse_pos_x > ctx->window.p0.x 
-		&& mouse_pos_x < ctx->window.p1.x 
-		&& mouse_pos_y > ctx->window.p0.y
-		&& mouse_pos_y < ctx->window.p1.y)
+	if (UIButton(ctx, "Show 2", 150.0f, 150.0f, 200.0f, 200.0f))
 	{
-		ctx->window.grabbed = true;
-
-		ctx->window.grabbed_pos.x = (f32)mouse_pos_x - ctx->window.p0.x;
-		ctx->window.grabbed_pos.y = (f32)mouse_pos_y - ctx->window.p0.y;
-	}
-	else if (!mouse_pressed && ctx->window.grabbed)
-	{
-		ctx->window.grabbed = false;
-
-		ctx->window.grabbed_pos.x = 0.0f;
-		ctx->window.grabbed_pos.y = 0.0f;
+		UIWindow(ctx, "Window 2", 500.0f, 500.0f, 600.0f, 600.0f);
 	}
 
-	if (ctx->window.grabbed)
+	if (UIButton(ctx, "Show 1", 50.0f, 50.0f, 100.0f, 100.0f))
 	{
-		f32 w = ctx->window.p1.x - ctx->window.p0.x;
-		f32 h = ctx->window.p1.y - ctx->window.p0.y;
-
-		ctx->window.p0.x = (f32)(mouse_pos_x) - ctx->window.grabbed_pos.x;
-		ctx->window.p0.y = (f32)(mouse_pos_y) - ctx->window.grabbed_pos.y;
-		ctx->window.p1.x = ctx->window.p0.x + w;
-		ctx->window.p1.y = ctx->window.p0.y + h;
+		UIWindow(ctx, "Window 1", 200.0f, 200.0f, 400.0f, 400.0f);
 	}
 
-	DrawRect(&ctx->gui, ctx->window.p0, ctx->window.p1, (Vec4){ .r = 0.1f, .g = 0.3f, .b = 0.8f, .a = 1.0f });
+	if (UIButton(ctx, "Show 3", 150.0f, 300.0f, 200.0f, 350.0f))
+	{
+		UIWindow(ctx, "Window 3", 250.0f, 500.0f, 400.0f, 650.0f);
+	}
+
+
+	GetViewportSize(&ctx->pc.res);
+
 
 	RenderBuffer *vertex_buffer = ArenaAlloc(ctx->arena, sizeof(RenderBuffer));
 	vertex_buffer->type = RENDER_BUFFER_TYPE_VERTEX;
diff --git a/src/game.h b/src/game.h
index a3d8164..df80eb7 100644
--- a/src/game.h
+++ b/src/game.h
@@ -5,15 +5,28 @@ typedef struct GUIWindow_t
 	Vec2 p0;
 	Vec2 p1;
 	Vec2 grabbed_pos;
+	u32 id;
 	b8 grabbed;
 } GUIWindow;
 
+typedef struct GUIButton_t
+{
+	Vec2 p0;
+	Vec2 p1;
+	u32	 id;
+	b8 	 pressed;
+	b8 	 pressed_prev;
+} GUIButton;
+
 typedef struct GameContext_t 
 {
 	GUIContext gui;
-	PushConst pc;
-	Arena *arena;
-	GUIWindow window;
+	PushConst  pc;
+	Arena      *arena;
+	GUIWindow  *windows;
+	u32        window_len;
+	GUIButton  *buttons;
+	u32        btn_len;
 } GameContext;
 
 static void RunCycle(GameContext *ctx, GameInput *inputs, u32 i_count);
diff --git a/src/platform/platform_linux.c b/src/platform/platform_linux.c
index cb1b478..8ccb46b 100644
--- a/src/platform/platform_linux.c
+++ b/src/platform/platform_linux.c
@@ -323,7 +323,7 @@ u8 *OSOpenFile(const char *)
 	return bytes;
 }
 
-b32 _ShouldQuit()
+b32 ShouldQuit()
 {
 	return false;
 }
diff --git a/src/platform/platform_windows.c b/src/platform/platform_windows.c
index 31ed4c0..8853060 100644
--- a/src/platform/platform_windows.c
+++ b/src/platform/platform_windows.c
@@ -201,7 +201,7 @@ void WaitForWindowEvent()
 	}
 }
 
-b32 _ShouldQuit()
+b32 ShouldQuit()
 {
 	return global_quit;
 }
diff --git a/src/shared_types.h b/src/shared_types.h
index c7aa5ac..7f62ddb 100644
--- a/src/shared_types.h
+++ b/src/shared_types.h
@@ -255,4 +255,5 @@ typedef struct
 	u32 *indices;
 	u32 indices_len;
 	u32 instance_count;
+	b8 	has_grabbed;
 } GUIContext;