diff --git a/src/simulation.cpp b/src/simulation.cpp
index d38075a..54e769b 100644
--- a/src/simulation.cpp
+++ b/src/simulation.cpp
@@ -1,15 +1,15 @@
 #include "simulation.h"
 #include "input.h"
-#include <cstdint>
-#include <ranges>
-#include <random>
-#include <algorithm>
-#include <clay/clay.h>
 #include <SDL3/SDL_log.h>
 #include <SDL3/SDL_render.h>
+#include <algorithm>
+#include <clay/clay.h>
+#include <cstdint>
+#include <set>
+#include <vector>
 
 namespace simulation {
-std::set<Cell> living{};
+static std::set<Cell> living{};
 static std::vector<Cell> overpopulated{};
 static std::vector<Cell> underpopulated{};
 static std::vector<Cell> born{};