diff --git a/sand.flan b/sand.flan
index 6afc3b6..3df4e51 100644
--- a/sand.flan
+++ b/sand.flan
@@ -12,8 +12,8 @@
 (defn dyn->f64 [v f64] f64 v)
 (defn dyn->u32 [v i64] u32 (u32 v))
 
-(defvar gravity dyn 0.05)
-(defvar colors dyn
+(def gravity dyn 0.05)
+(def colors dyn
   (let [v (vec-new dyn)]
     (push v 0xFFF00FFF)
     (push v 0x3B6E8CFF)
@@ -21,9 +21,9 @@
     (push v 0xCC6B1FFF)
     v))
 
-(defvar grid     [rows [cols u32]])
-(defvar velocity [rows [cols f32]])
-(defvar current-color dyn 0)
+(defonce grid     [rows [cols u32]])
+(defonce velocity [rows [cols f32]])
+(defonce current-color dyn 0)
 
 (defn clear-grid [] ()
   (set grid     (zeroed))
@@ -112,8 +112,8 @@
                              (rl/get-color c))))))
   (rl/draw-fps 20 20))
 
-(defvar frame Allocator (arena-new 262144))
-(defvar game-data dyn
+(defonce frame Allocator (arena-new 262144))
+(def game-data dyn
   (handler-case (edn/read-file "game-data.edn")
     [(FileError [c] nil)]))