diff --git a/frontend/apps/filemanager/filemanagerhistory.lua b/frontend/apps/filemanager/filemanagerhistory.lua
index a79999f66..cd266a46b 100644
--- a/frontend/apps/filemanager/filemanagerhistory.lua
+++ b/frontend/apps/filemanager/filemanagerhistory.lua
@@ -1,7 +1,6 @@
 local InputContainer = require("ui/widget/container/inputcontainer")
 local CenterContainer = require("ui/widget/container/centercontainer")
 local ButtonDialog = require("ui/widget/buttondialog")
-local ReaderUI = require("apps/reader/readerui")
 local lfs = require("libs/libkoreader-lfs")
 local UIManager = require("ui/uimanager")
 local DocSettings = require("docsettings")
@@ -79,6 +78,7 @@ function FileManagerHistory:addToMainMenu(tab_item_table)
 end
 
 function FileManagerHistory:updateItemTable()
+    local ReaderUI = require("apps/reader/readerui")
     self.hist = {}
 
     for f in lfs.dir(history_dir) do
diff --git a/frontend/apps/filemanager/filemanagersearch.lua b/frontend/apps/filemanager/filemanagersearch.lua
index 773077ab8..d4add2dc1 100644
--- a/frontend/apps/filemanager/filemanagersearch.lua
+++ b/frontend/apps/filemanager/filemanagersearch.lua
@@ -3,7 +3,6 @@ local InputContainer = require("ui/widget/container/inputcontainer")
 local DocumentRegistry = require("document/documentregistry")
 local InputDialog = require("ui/widget/inputdialog")
 local InfoMessage = require("ui/widget/infomessage")
-local ReaderUI = require("apps/reader/readerui")
 local lfs = require("libs/libkoreader-lfs")
 local UIManager = require("ui/uimanager")
 local Menu = require("ui/widget/menu")
@@ -498,6 +497,7 @@ function Search:onMenuHold(item)
 end
 
 function Search:showresults()
+    local ReaderUI = require("apps/reader/readerui")
     local menu_container = CenterContainer:new{
         dimen = Screen:getSize(),
     }
@@ -544,6 +544,7 @@ function Search:showresults()
 end
 
 function Search:browse(option,run,chosen)
+    local ReaderUI = require("apps/reader/readerui")
     local restart_me = false
     local menu_container = CenterContainer:new{
         dimen = Screen:getSize(),
diff --git a/frontend/ui/device.lua b/frontend/ui/device.lua
index 4e36f8d5d..cba781791 100644
--- a/frontend/ui/device.lua
+++ b/frontend/ui/device.lua
@@ -1,8 +1,4 @@
-local AndroidPowerd = require("ui/device/androidpowerd")
-local KindlePowerD = require("ui/device/kindlepowerd")
 local isAndroid, android = pcall(require, "android")
-local KoboPowerD = require("ui/device/kobopowerd")
-local BasePowerD = require("ui/device/basepowerd")
 local lfs = require("libs/libkoreader-lfs")
 local Screen = require("ui/device/screen")
 local util = require("ffi/util")
@@ -288,12 +284,16 @@ function Device:getPowerDevice()
     else
         local model = self:getModel()
         if model == "KindleTouch" or model == "KindlePaperWhite" or model == "KindlePaperWhite2" then
+            local KindlePowerD = require("ui/device/kindlepowerd")
             self.powerd = KindlePowerD:new{model = model}
         elseif self:isKobo() then
+            local KoboPowerD = require("ui/device/kobopowerd")
             self.powerd = KoboPowerD:new()
         elseif self.isAndroid then
+            local AndroidPowerd = require("ui/device/androidpowerd")
             self.powerd = AndroidPowerd:new()
         else -- emulated FrontLight
+            local BasePowerD = require("ui/device/basepowerd")
             self.powerd = BasePowerD:new()
         end
     end
@@ -322,4 +322,13 @@ function Device:isSpecialOffers()
     return self.is_special_offers
 end
 
+-- FIXME: this is a dirty hack, normally we don't need to get power device this early,
+-- but Kobo devices somehow may need to init the frontlight module at startup?
+-- because `kobolight = require("ffi/kobolight")` used to be in the `koreader-base` script
+-- and run as the first line of koreader script no matter which device you are running on, 
+-- which is utterly ugly. So I refactored it into the `init` method of `kobopowerd` and
+-- `kobolight` will be init here. It's pretty safe to comment this line for non-kobo devices
+-- so if kobo users find this line is useless, please don't hesitate to get rid of it.
+local dummy_powerd = Device:getPowerDevice()
+
 return Device
diff --git a/frontend/ui/device/kobopowerd.lua b/frontend/ui/device/kobopowerd.lua
index 0816276d0..103ed5446 100644
--- a/frontend/ui/device/kobopowerd.lua
+++ b/frontend/ui/device/kobopowerd.lua
@@ -5,7 +5,7 @@ local KoboPowerD = BasePowerD:new{
     flIntensity = 20,
     restore_settings = true,
     fl = nil,
-    
+
     batt_capacity_file = "/sys/devices/platform/pmic_battery.1/power_supply/mc13892_bat/capacity",
     is_charging_file = "/sys/devices/platform/pmic_battery.1/power_supply/mc13892_bat/charge_now",
     battCapacity = nil,
@@ -13,6 +13,7 @@ local KoboPowerD = BasePowerD:new{
 }
 
 function KoboPowerD:init()
+    local kobolight = require("ffi/kobolight")
     local ok, light = pcall(kobolight.open)
     if ok then self.fl = light end
 end
diff --git a/reader.lua b/reader.lua
index ef59703fd..f463fcba1 100755
--- a/reader.lua
+++ b/reader.lua
@@ -1,4 +1,4 @@
-#!./koreader-base
+#!./luajit
 
 require "defaults"
 pcall(dofile, "defaults.persistent.lua")
@@ -100,6 +100,7 @@ local function showusage()
     return
 end
 
+local ARGV = arg
 local argidx = 1
 while argidx <= #ARGV do
     local arg = ARGV[argidx]
diff --git a/wtest.lua b/utils/wtest.lua
similarity index 99%
rename from wtest.lua
rename to utils/wtest.lua
index 24ec22c3a..e9112f7fd 100755
--- a/wtest.lua
+++ b/utils/wtest.lua
@@ -1,4 +1,5 @@
-#!./koreader-base
+-- widget test utility
+-- usage: ./luajit util/wtest.lua
 
 require "defaults"
 print(package.path)