diff --git a/517random.mu b/517random.mu
index 0e907442..1f75b068 100644
--- a/517random.mu
+++ b/517random.mu
@@ -9,3 +9,10 @@ fn next-random prev: int -> _/edi: int {
   next <- remainder next, m
   return next
 }
+
+fn remainder a: int, b: int -> _/eax: int {
+  var q/eax: int <- copy 0
+  var r/edx: int <- copy 0
+  q, r <- integer-divide a, b
+  return r
+}
diff --git a/apps/tile.mu b/apps/tile.mu
index c7067e83..6ac49d39 100644
--- a/apps/tile.mu
+++ b/apps/tile.mu
@@ -308,10 +308,3 @@ fn render-tile-without-margin screen: (addr screen), _tile: (addr tile), start-x
     loop
   }
 }
-
-fn remainder a: int, b: int -> _/eax: int {
-  var q/eax: int <- copy 0
-  var r/edx: int <- copy 0
-  q, r <- integer-divide a, b
-  return r
-}