diff --git a/node.lua b/node.lua
index b7fd7eb..50da3d6 100644
--- a/node.lua
+++ b/node.lua
@@ -96,12 +96,6 @@ local function check_next_talks()
             all_next_talks[#all_next_talks+1] = talk
         end
     end
-
-    local function sort_talks(a, b)
-        return a.start_ts < b.start_ts or (a.start_ts == b.start_ts and a.room < b.room)
-    end
-
-    table.sort(all_next_talks, sort_talks)
 end
 
 local function wrap(str, font, size, max_w)
diff --git a/service b/service
index a7266f9..d3f5965 100755
--- a/service
+++ b/service
@@ -151,6 +151,7 @@ def main():
                             "color": color,
                         }
                     )
+                schedule["talks"] = sorted(schedule["talks"], key=lambda t: t["start_ts"])
                 node.write_json("schedule.json", schedule)
                 log("updated schedule json")
         elif config["json_flavour"] == "voc-schema":
@@ -236,6 +237,7 @@ def main():
                             talk["persons"] = persons
 
                             schedule["talks"].append(talk)
+                schedule["talks"] = sorted(schedule["talks"], key=lambda t: t["start_ts"])
                 node.write_json("schedule.json", schedule)
                 log("updated schedule json")
         else:
diff --git a/tile.lua b/tile.lua
index 7d1becc..318d810 100644
--- a/tile.lua
+++ b/tile.lua
@@ -151,13 +151,6 @@ local function check_next_talks()
         end
     end
 
-    local function sort_talks(a, b)
-        return a.start_ts < b.start_ts or (a.start_ts == b.start_ts and a.room < b.room)
-    end
-
-    table.sort(room_next_talks, sort_talks)
-    table.sort(all_next_talks, sort_talks)
-
     log(tostring(#all_next_talks) .. " talks to come")
     log(tostring(#room_next_talks) .. " in this room")
 end