diff --git a/src/main/lemondronor/circlebot.cljs b/src/main/lemondronor/circlebot.cljs
index a592b4e..4ec0556 100644
--- a/src/main/lemondronor/circlebot.cljs
+++ b/src/main/lemondronor/circlebot.cljs
@@ -463,9 +463,12 @@
                                             lon)
                              (log-warn "Skipping tweeting"))
                             (let [path (str (.toFixed (/ now 1000) 0) "-" icao ".geojson")]
-                              (util/write-file path (.stringify
-                                                     js/JSON
-                                                     (clj->js (util/->geojson recent-positions icao centroid))))))
+                              (util/write-file
+                               path
+                               (.stringify
+                                js/JSON
+                                (clj->js (util/->geojson recent-positions icao centroid)))
+                               {})))
                           (log-warn "Skipping tweet %s %s" image-path description)))))))))))