diff --git a/arena.h b/arena.h
index 03db2ce..a6561b6 100644
--- a/arena.h
+++ b/arena.h
@@ -32,7 +32,7 @@ struct Arena_Region {
     uint8_t data[];
 };
 
-typedef struct {
+typedef struct Arena {
     Arena_Region *head;
     Arena_Region *tail;
     size_t region_capacity;