diff --git a/adjust_time.coffee b/adjust_time.coffee
deleted file mode 100644
index 755a3ba..0000000
--- a/adjust_time.coffee
+++ /dev/null
@@ -1,84 +0,0 @@
-util = require 'util'
-{ spawn, execSync } = require 'child_process'
-dayjs = require 'dayjs'
-delay = require './delay'
-dayjs.extend require './dayjs_format_ms'
-platform = require('os').platform()
-
-
-adjust_time = (delta, adjust_command) ->
-  console.log 'Adjust time...'
-  shell = spawn spawn_args...
-  shell.stderr.on 'data', (data) -> console.error "> " + "#{data}".trim()
-  shell.stdout.on 'data', (data) -> console.debug "> " + "#{data}".trim()
-  shell.on 'close', (code) ->
-    shell.stdin.end()
-    console.log 'Done'
-    process.exit 0
-  wait_data = util.promisify (cb) ->
-    shell.stdout.once 'data', (chunk) ->
-      setTimeout ->
-        cb null, chunk
-      , 1
-  input_line = util.promisify (cmd, cb) ->
-    console.debug "$ #{cmd}"
-    shell.stdin.write "#{cmd}\n", (p...) ->
-      await wait_data() if platform in ['win32']
-      cb p...
-  if platform in ['win32']
-    await wait_data()
-    new_time = dayjs().add(delta, 'ms')
-    cmd = new_time.format adjust_command
-  else
-    adjust_command = adjust_command.replace /ss\.S+/, 'ss'
-    new_time = dayjs().add(delta, 'ms')
-    ms = new_time.get('millisecond')
-    if ms > 0
-      wait_time = 1000 - ms
-      new_time = new_time.add(wait_time, 'ms')
-      delay wait_time
-    cmd = new_time.format adjust_command
-  await input_line cmd
-  await input_line 'exit'
-
-
-# win32: get local date format by command:
-# reg query "HKCU\Control Panel\International" /v sShortDate
-#* @see # https://calendars.wikia.org/wiki/Date_format_by_country
-if platform isnt 'win32'
-  adjust_time.COMMAND = '[date -s ]"YYYY-MM-DD HH:mm:ss"'
-else
-  date_format = 'MM-DD-YY'
-  try
-    date_format_raw = ('' + execSync(
-      'reg query "HKCU\\Control Panel\\International" /v sShortDate'
-    )).trim().split(/[\n\r]+/).pop()?.trim().split(/\s+/).pop()
-  catch err
-    null
-  if date_format_raw and date_format_raw isnt ''
-    date_format = date_format_raw.
-      replace(/[^YMDymd]+/g, '-').
-      replace(/y+/gi, 'YY').
-      replace(/m+/gi, 'MM').
-      replace(/d+/gi, 'DD')
-  adjust_time.COMMAND = '[time ]HH:mm:ss.SS[ && date ]' + date_format
-
-
-SHELL_ARGS = {
-  win32: [
-    'cmd'
-    ['/q', '/k', 'prompt $H && chcp 65001 > nul']
-    {
-      windowsHide: true
-    }
-  ]
-  linux: [
-    'sh'
-  ]
-}
-spawn_args = SHELL_ARGS[platform] or SHELL_ARGS.linux
-if not /UTF\-8/i.test (process.env.LANGUAGE or '')
-  process.env.LANGUAGE = 'C.UTF-8'
-
-
-module.exports = adjust_time
\ No newline at end of file