             type: 'POST'
 
     pause: (killTasks, duration) =>
+        data =
+            user:      app.getUsername()
+            killTasks: killTasks
+        duration = @_parseDuration(duration)
+        if duration
+            data[durationMillis] = duration
         $.ajax
             url:         "#{ @url() }/pause"
             type:        'POST'
             contentType: 'application/json'
-            data:         JSON.stringify
-                user:      app.getUsername()
-                killTasks: killTasks
-                durationMillis: @_parseDuration(duration)
+            data: JSON.stringify data
 
     run: (confirmedOrPromptData) ->
         options =

        $.ajax options

    scale: (confirmedOrPromptData) =>
        $.ajax
          url: "#{ @url() }/scale?user=#{ app.getUsername() }"
          type: "PUT"
          contentType: 'application/json'
          data: JSON.stringify
              instances: confirmedOrPromptData.instances
              durationMillis: @_parseDuration(confirmedOrPromptData.duration)

    makeScalePermanent: (callback) =>
        $.ajax(

        ).then callback

    bounce: (incremental, duration) =>
        data =
            incremental: incremental
        duration = @_parseDuration(duration)
        if duration
            data[durationMillis] = duration
        $.ajax
            type: "POST"
            url:  "#{ @url() }/bounce?user=#{ app.getUsername() }"
            contentType: 'application/json'
            data: JSON.stringify data

    exitCooldown: =>
        $.ajax
