diff --git a/mem/include/arena/mem_arena.h b/mem/include/arena/mem_arena.h
index 29d76b2..5494ebc 100644
--- a/mem/include/arena/mem_arena.h
+++ b/mem/include/arena/mem_arena.h
@@ -11,7 +11,7 @@ extern "C" {
 
 typedef struct growing_arena Arena;
 
-Allocator wapp_mem_arena_allocator(Arena *arena);
+Allocator wapp_mem_arena_allocator(const Arena *arena);
 bool wapp_mem_arena_init(Arena **arena, u64 base_capacity);
 void *wapp_mem_arena_alloc(Arena *arena, u64 size);
 void *wapp_mem_arena_alloc_aligned(Arena *arena, u64 size, u64 alignment);
diff --git a/mem/src/arena/mem_arena.c b/mem/src/arena/mem_arena.c
index f7e07ff..13a1bca 100644
--- a/mem/src/arena/mem_arena.c
+++ b/mem/src/arena/mem_arena.c
@@ -59,7 +59,7 @@ internal void *mem_arena_realloc_aligned(void *ptr, u64 size, u64 alignment,
 
 // PUBLIC API
 
-Allocator wapp_mem_arena_allocator(Arena *arena) {
+Allocator wapp_mem_arena_allocator(const Arena *arena) {
   return (Allocator){
       .obj = (void *)arena,
       .alloc = mem_arena_alloc,