diff --git a/program/Boot.cs b/program/Boot.cs
new file mode 100644
index 0000000..62f1ffc
--- /dev/null
+++ b/program/Boot.cs
@@ -0,0 +1,15 @@
+using System;
+using System.Diagnostics;
+
+public static class Boot
+{
+    private static readonly Stopwatch _sw = Stopwatch.StartNew();
+    private static long _last;
+
+    public static void Mark(string what)
+    {
+        long now = _sw.ElapsedMilliseconds;
+        Console.WriteLine("[boot] " + now.ToString().PadLeft(6) + " ms  (+" + (now - _last) + ")  " + what);
+        _last = now;
+    }
+}
\ No newline at end of file
diff --git a/program/MainWindow.cs b/program/MainWindow.cs
index 51bd443..bdd42c2 100644
--- a/program/MainWindow.cs
+++ b/program/MainWindow.cs
@@ -62,6 +62,7 @@
     private BatteryStatus _battery = new BatteryStatus();
     private uint _batteryTimerId;
     private const uint BatteryPollMs = 10000;
+    
 
     public MainWindow() : this(CreateBuilder()) { }
 
@@ -140,10 +141,13 @@
         ConnectionAlertLabel.Name = "ConnectionAlertLabel";
         _Language.Register("ConnectionAlertLabel", ConnectionAlertLabel);
 
+        // Boot.Mark("before settings");
         _settingsWindow = new SettingsWindow(builder, _arduino, _Language);
+        // Boot.Mark("settings window");
         _settingsWindow.BackRequested += OnSettingsClosed;
 
         _mapWindow = new MapWindow(builder, _arduino, _Language);
+        // Boot.Mark("map window");
         _mapWindow.BackRequested += OnMapClosed;
 
         _Language.Changed += (s, e) => {