diff --git a/installer_bi.lua b/installer_bi.lua
deleted file mode 100644
index 5c44dfc..0000000
--- a/installer_bi.lua
+++ /dev/null
@@ -1,164 +0,0 @@
-local URL_ERROR = "http://cloud.fse-media.group/d/API/TicketMachine/error.dfpwm?sign=DvQ39wQDN6Cej4KPhAkM3JyXPM466koan6w9CckPxWU=:0"
-local URL_PASS = "http://cloud.fse-media.group/d/API/TicketMachine/pass.dfpwm?sign=ZJfGDYnaxQU4JrGSh4NDzKZtjq3eMjYh9KHmMSAMKZA=:0"
-local URL_GATE = "http://cloud.fse-media.group/d/API/TicketMachine/gate.lua?sign=OWy1wKkKhUhpnxXKeX6fRLePSg1XcaQgWOLvQbMuHRQ=:0"
-
-local CONFIG_PATH = "gate_config.json"
-
-local function trim(s)
-  return (tostring(s or ""):gsub("^%s+", ""):gsub("%s+$", ""))
-end
-
-local function splitCsv(s)
-  local out = {}
-  s = trim(s)
-  if #s == 0 then return out end
-  for part in s:gmatch("[^,/%s]+") do
-    local v = trim(part)
-    if #v > 0 then table.insert(out, v) end
-  end
-  return out
-end
-
-local function writeFile(path, content, binary)
-  local mode = binary and "wb" or "w"
-  local f = fs.open(path, mode)
-  if not f then return false end
-  f.write(content)
-  f.close()
-  return true
-end
-
-local function prompt(label)
-  term.write(label)
-  return trim(read() or "")
-end
-
-local function promptOptionalUrl(label)
-  local raw = prompt(label)
-  raw = trim(raw)
-  if #raw == 0 then return nil end
-  return raw
-end
-
-local function httpGet(url)
-  if not http then return false, "HTTP API disabled" end
-  local okReq, err = pcall(function()
-    http.request({ url = url, method = "GET" })
-  end)
-  if not okReq then return false, tostring(err) end
-
-  while true do
-    local ev, p1, p2, p3 = os.pullEvent()
-    if ev == "http_success" and p1 == url then
-      local res = p2
-      if type(res) == "table" and type(res.readAll) == "function" then
-        local data = res.readAll()
-        res.close()
-        return true, data
-      end
-      return false, "invalid http response"
-    end
-    if ev == "http_failure" and p1 == url then
-      local err = p2
-      local res = p3
-      if type(p2) == "table" and type(p2.readAll) == "function" then
-        res = p2
-        err = p3
-      end
-      if type(res) == "table" and type(res.readAll) == "function" then
-        local data = res.readAll()
-        res.close()
-        return false, data
-      end
-      return false, tostring(err or "http_failure")
-    end
-  end
-end
-
-local function download(url, path, binary)
-  print("Downloading: " .. path)
-  local ok, data = httpGet(url)
-  if not ok then
-    print("Download failed: " .. tostring(data or ""))
-    return false
-  end
-  if not writeFile(path, data, binary) then
-    print("Write failed: " .. path)
-    return false
-  end
-  return true
-end
-
-local function normalizeMode(raw)
-  return (trim(raw):lower() == "exit") and "exit" or "entry"
-end
-
-term.clear()
-term.setCursorPos(1, 1)
-print("Bidirectional Ticket Gate Installer")
-print("")
-
-local stationsRaw = prompt("Station codes (comma or slash): ")
-local stationCodes = splitCsv(stationsRaw)
-if #stationCodes == 0 then
-  print("No station codes provided.")
-  return
-end
-
-print("")
-print("Set mode for each side (front/back).")
-local frontRaw = prompt("Front mode (entry/exit): ")
-local backRaw = prompt("Back mode (entry/exit): ")
-local frontMode = normalizeMode(frontRaw)
-local backMode = normalizeMode(backRaw)
-local frontStationCode = trim(prompt("Front station code (default first code): "))
-local backStationCode = trim(prompt("Back station code (default first code): "))
-if #frontStationCode == 0 then frontStationCode = stationCodes[1] end
-if #backStationCode == 0 then backStationCode = stationCodes[1] end
-
-print("")
-print("Optional server config for ticket / IC card checks.")
-local ticketServerUrl = promptOptionalUrl("Ticket check URL (blank=auto): ")
-local cardServerUrl = promptOptionalUrl("IC card check URL (blank=same server): ")
-
-local cfg = {
-  station_codes = stationCodes,
-  station_code = stationCodes[1],
-  side_modes = {
-    front = frontMode,
-    back = backMode,
-  },
-  side_station_codes = {
-    front = frontStationCode,
-    back = backStationCode,
-  }
-}
-if ticketServerUrl then cfg.server_url = ticketServerUrl end
-if cardServerUrl then cfg.card_server_url = cardServerUrl end
-local okCfg, cfgJson = pcall(textutils.serializeJSON, cfg)
-if not okCfg then
-  print("Config serialize failed.")
-  return
-end
-if not writeFile(CONFIG_PATH, cfgJson, false) then
-  print("Failed to write config.")
-  return
-end
-
-if not download(URL_PASS, "pass.dfpwm", true) then return end
-if not download(URL_ERROR, "error.dfpwm", true) then return end
-
-local okGate, gateCode = httpGet(URL_GATE)
-if not okGate then
-  print("Download failed: startup")
-  return
-end
-
-writeFile("startup.lua", gateCode, false)
-writeFile("startup", gateCode, false)
-
-print("")
-print("Done.")
-print("This gate now supports tickets and IC cards.")
-print("Attach ticket_inspection_machine on FRONT and BACK.")
-print("Reboot the computer to start the gate.")