diff --git a/Makefile b/Makefile
index 7269515..fe34670 100644
--- a/Makefile
+++ b/Makefile
@@ -3,7 +3,10 @@ clean:
 	mkdir out/
 
 compile:
-	gcc -W -Wall -Wextra -pedantic -o out/main src/main.c -Iinclude -lpthread -Llib -lSDL3
+	gcc -W -Wall -Wextra -pedantic -o out/main src/main.c src/utils/arena.c src/utils/vector.c -Iinclude -Iutils -lpthread -Llib -lSDL3
+
+debug:
+	gcc -W -Wall -Wextra -pedantic -g -O0 -o out/main_debug src/main.c src/utils/arena.c src/utils/vector.c -Iinclude -Iutils -lpthread -Llib -lSDL3
 
 run:
 	make compile	
diff --git a/src/main.c b/src/main.c
index df063a8..c5ec36c 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1,8 +1,10 @@
 #define SDL_MAIN_USE_CALLBACKS 1
+#include "utils/arena.h"
+#include "utils/vector.h"
 #include <SDL3/SDL.h>
 #include <SDL3/SDL_main.h>
 
-#define FPS 60
+// #define FPS 60
 #define STEP_RATE_MS 500
 
 static SDL_Window *window = NULL;
@@ -10,7 +12,7 @@ static SDL_Renderer *renderer = NULL;
 
 #define WINDOW_WIDTH 640
 #define WINDOW_HEIGHT 480
-#define GRID_PADDING 2
+#define GRID_PADDING 4
 #define GRID_WIDTH 18
 #define GRID_HEIGHT 15
 #define TILE_WIDTH 24
@@ -28,22 +30,23 @@ typedef enum DIRECTION { LEFT, RIGHT, UP, DOWN } DIRECTION;
 
 typedef struct Snake {
   DIRECTION direction;
-  Uint8 length;
-  int head_index;
-  int tail_index;
+  int length;
+  Vector *body;
 } Snake;
 
 typedef struct State {
-  Uint8 grid[GRID_HEIGHT * GRID_WIDTH];
   Snake *player;
+  Vector *fruits;
   Uint64 last_frame;
 } State;
 
+static Arena arena;
+
 #define INDEX_AT(row, col) ((row) * GRID_WIDTH + (col))
-#define ROW_AT(index) (index / GRID_WIDTH)
-#define COL_AT(index) (index % GRID_WIDTH)
-#define SET_GRID_AT(grid, row, col, value) grid[INDEX_AT(row, col)] = value
-#define GET_GRID_AT(grid, row, col) grid[INDEX_AT(row, col)]
+#define ROW_AT(index) ((index) / GRID_WIDTH)
+#define COL_AT(index) ((index) % GRID_WIDTH)
+#define SET_GRID_AT(grid, row, col, value) (grid)[INDEX_AT((row), (col))] = (value)
+#define GET_GRID_AT(grid, row, col) (grid)[INDEX_AT((row), (col))]
 
 void log_game_grid(Uint8 *game_grid) {
   char buf[GRID_WIDTH * 2];
@@ -69,27 +72,25 @@ SDL_AppResult SDL_AppInit(void **appstate, int argc, char *argv[]) {
     return SDL_APP_FAILURE;
   }
 
-  State *state = SDL_malloc(sizeof(State));
+  arena_init(&arena, KB(42));
+  State *state = arena_alloc(&arena, 1, sizeof(State), _Alignof(State));
   if (!state) {
     SDL_Log("Failed to allocate state");
     return SDL_APP_FAILURE;
   }
-  SDL_memset(state->grid, EMPTY, sizeof(state->grid));
 
-  SET_GRID_AT(state->grid, GRID_HEIGHT / 2, GRID_WIDTH / 2, SNAKE);
-  SET_GRID_AT(state->grid, GRID_HEIGHT / 2, GRID_WIDTH / 2 - 1, SNAKE);
-  SET_GRID_AT(state->grid, GRID_HEIGHT / 2, GRID_WIDTH / 2 - 2, SNAKE);
-
-  state->player = SDL_malloc(sizeof(Snake));
+  state->player = arena_alloc(&arena, 1, sizeof(Snake), _Alignof(Snake));
+  if (!state->player) {
+    SDL_Log("Failed to allocate player");
+    return SDL_APP_FAILURE;
+  }
   state->player->direction = UP;
   state->player->length = 3;
-  state->player->head_index = INDEX_AT(GRID_HEIGHT / 2, GRID_WIDTH / 2);
-  state->player->tail_index = INDEX_AT(GRID_HEIGHT / 2, GRID_WIDTH / 2 - 2);
-
-  SET_GRID_AT(state->grid, 4, 12, FRUIT);
-  SET_GRID_AT(state->grid, 13, 5, FRUIT);
-
-  log_game_grid(state->grid);
+  state->player->body = (Vector *)arena_alloc(&arena, 1, sizeof(Vector), _Alignof(Vector));
+  if (!state->player->body) {
+    SDL_Log("Failed to allocate player body");
+    return SDL_APP_FAILURE;
+  }
 
   state->last_frame = SDL_GetTicks();
   *appstate = state;
@@ -126,71 +127,67 @@ SDL_AppResult SDL_AppEvent(void *appstate, SDL_Event *event) {
   }
 }
 
-void game_step(Uint8 **game_grid, Snake *player) {
-  SDL_Log("snek: %d %d %d %d", player->direction, player->length, player->head_index,
-          player->tail_index);
+void game_step(State *stateptr) {
+  // SDL_Log("snek: %d %d %d %d", player->direction, player->length, player->head_index,
+  //         player->tail_index);
+  Snake *playerptr = stateptr->player;
+  int head = vector_pop(stateptr->player->body);
+  vector_push(stateptr->player->body, head);
 
-  switch (player->direction) {
+  switch (playerptr->direction) {
   case RIGHT:
-    player->head_index = INDEX_AT(ROW_AT(player->head_index), COL_AT(player->head_index) + 1);
+    vector_push(playerptr->body, head + 1);
     break;
   case UP:
-    player->head_index = INDEX_AT(ROW_AT(player->head_index) - 1, COL_AT(player->head_index));
+    vector_push(playerptr->body, head - GRID_WIDTH);
     break;
   case LEFT:
-    player->head_index = INDEX_AT(ROW_AT(player->head_index), COL_AT(player->head_index) - 1);
+    vector_push(playerptr->body, head - 1);
     break;
   case DOWN:
-    player->head_index = INDEX_AT(ROW_AT(player->head_index) + 1, COL_AT(player->head_index));
+    vector_push(playerptr->body, head + GRID_WIDTH);
     break;
   }
 }
 
 SDL_AppResult SDL_AppIterate(void *appstate) {
   State *stateptr = appstate;
-  Uint8 *game_grid = stateptr->grid;
-  Snake *player = stateptr->player;
+  Snake *playerptr = stateptr->player;
 
   const Uint64 now = SDL_GetTicks();
 
   // step multiple times if we are behind
   while (now - stateptr->last_frame >= STEP_RATE_MS) {
-    game_step(&game_grid, player);
+    game_step(stateptr);
     stateptr->last_frame += STEP_RATE_MS;
   }
 
-  SET_GRID_AT(game_grid, ROW_AT(player->head_index), COL_AT(player->head_index), SNAKE);
-  SET_GRID_AT(game_grid, ROW_AT(player->tail_index), COL_AT(player->tail_index), SNAKE);
-
-  SDL_SetRenderDrawColor(renderer, COLOR_BG);
-  SDL_RenderClear(renderer);
-
   SDL_FRect rect;
   rect.w = TILE_WIDTH;
   rect.h = TILE_HEIGHT;
   const int startx = (WINDOW_WIDTH - GRID_WIDTH * (TILE_WIDTH + GRID_PADDING)) / 2;
   const int starty = (WINDOW_HEIGHT - GRID_HEIGHT * (TILE_HEIGHT + GRID_PADDING)) / 2;
 
+  SDL_SetRenderDrawColor(renderer, COLOR_BG);
+  SDL_RenderClear(renderer);
+
+  SDL_SetRenderDrawColor(renderer, COLOR_EMPTY);
   for (int i = 0; i < GRID_HEIGHT; i++) {
     for (int j = 0; j < GRID_WIDTH; j++) {
-      switch (GET_GRID_AT(game_grid, i, j)) {
-      case EMPTY:
-        SDL_SetRenderDrawColor(renderer, COLOR_EMPTY);
-        break;
-      case SNAKE:
-        SDL_SetRenderDrawColor(renderer, COLOR_SNAKE);
-        break;
-      case FRUIT:
-        SDL_SetRenderDrawColor(renderer, COLOR_FRUIT);
-        break;
-      }
       rect.x = startx + j * (rect.w + GRID_PADDING);
       rect.y = starty + i * (rect.h + GRID_PADDING);
       // SDL_Log("x: %f, y: %f, w: %f, h: %f", rect.x, rect.y, rect.w, rect.h);
       SDL_RenderFillRect(renderer, &rect);
     }
   }
-  // SDL_Log("---");
+
+  SDL_SetRenderDrawColor(renderer, COLOR_SNAKE);
+  for (int i = 0; i < playerptr->length; i++) {
+    int b = playerptr->body->data[i];
+    rect.x = startx + ROW_AT(b) * (rect.w + GRID_PADDING);
+    rect.y = starty + COL_AT(b) * (rect.h + GRID_PADDING);
+    SDL_RenderFillRect(renderer, &rect);
+  }
 
   SDL_RenderPresent(renderer);
 
@@ -199,6 +196,5 @@ SDL_AppResult SDL_AppIterate(void *appstate) {
 
 void SDL_AppQuit(void *appstate, SDL_AppResult result) {
   /* SDL will clean up the window/renderer for us. */
-  SDL_free(((State *)appstate)->player);
-  SDL_free(appstate);
-}
\ No newline at end of file
+  arena_free(&arena);
+}
diff --git a/src/utils/arena.c b/src/utils/arena.c
index e11c817..1d2e7b6 100644
--- a/src/utils/arena.c
+++ b/src/utils/arena.c
@@ -46,17 +46,17 @@ void arena_free(Arena *a) {
   free(a);
 }
 
-int main(void) {
-  printf("this is the `arena.c` utility main method.\n");
+// int main(void) {
+//   printf("this is the `arena.c` utility main method.\n");
 
-  Arena a = {0};
-  arena_init(&a, KB(2));
+//   Arena a = {0};
+//   arena_init(&a, KB(2));
 
-  int *t = arena_alloc(&a, 6, sizeof(int), _Alignof(int));
+//   int *t = arena_alloc(&a, 6, sizeof(int), _Alignof(int));
 
-  for (int *i = t; i < t + 6; i++) {
-    printf("%d ", *i);
-  }
+//   for (int *i = t; i < t + 6; i++) {
+//     printf("%d ", *i);
+//   }
 
-  return 0;
-}
+//   return 0;
+// }
diff --git a/src/utils/vector.c b/src/utils/vector.c
index 3a751d3..2c8b16c 100644
--- a/src/utils/vector.c
+++ b/src/utils/vector.c
@@ -48,6 +48,10 @@ void vector_pusha(Vector *v, int *vals, int n) {
 }
 
 int vector_pop(Vector *v) {
+  if (v->size < 1) {
+    printf("vector_pop: popping empty vector");
+    return 0;
+  }
   int val = v->data[v->size - 1];
   v->size--;
   return val;
@@ -68,13 +72,13 @@ void vector_print(Vector v) {
   printf("\n");
 }
 
-int main(int argc, char *argv[]) {
-  Vector *v = vector_new();
-  vector_push(v, 20);
-  vector_pusha(v, (int[]){1, 2, 3}, 3);
-  vector_print(*v);
-  printf("oops, i removed %d\n", vector_pop(v));
-  vector_print(*v);
-  vector_free(v);
-  return 0;
-}
+// int main(int argc, char *argv[]) {
+//   Vector *v = vector_new();
+//   vector_push(v, 20);
+//   vector_pusha(v, (int[]){1, 2, 3}, 3);
+//   vector_print(*v);
+//   printf("oops, i removed %d\n", vector_pop(v));
+//   vector_print(*v);
+//   vector_free(v);
+//   return 0;
+// }