diff --git a/README.md b/README.md
--- a/README.md
+++ b/README.md
@@ -14,8 +14,7 @@
 
 ### Installation
 
-`dprox` should build and work on all unix-like OS with [ghc](https://www.haskell.org/ghc/) support, but it's only
-been tested on Linux and macOS.
+`dprox` should build and work on all unix-like OS with [ghc](https://www.haskell.org/ghc/) support, as well as Windows.
 
 While `dprox` can be built with [cabal](https://www.haskell.org/cabal/) like any other Hackage packages, for a
 reliable compilation with pinned dependencies, [stack](https://docs.haskellstack.org/en/stable/README/#how-to-install) is generally recommended.
@@ -35,7 +34,6 @@
 Here is the list of implemented dnsmasq options (with `server`, `local`, `address` and `bogus-nxdomain` options allowed in configuration file):
 
 ```
--u, --user=<username>
 -p, --port=<port>
 -a, --listen-address=<ipaddr>
 -C, --conf-file=<file>
diff --git a/dprox.cabal b/dprox.cabal
--- a/dprox.cabal
+++ b/dprox.cabal
@@ -5,7 +5,7 @@
 -- see: https://github.com/sol/hpack
 
 name:           dprox
-version:        0.4.0
+version:        0.4.1
 synopsis:       a lightweight DNS proxy server, compatible with dnsmasq-china-list
 description:    Please see the README on GitHub at <https://github.com/bjin/dprox#readme>
 category:       DNS
@@ -58,7 +58,6 @@
     , psqueues >=0.2.3
     , streaming-commons >=0.2
     , time >=1.8
-    , unix >=2.7
   default-language: Haskell2010
   if flag(static)
     ghc-options: -optl-static
@@ -90,7 +89,6 @@
     , psqueues >=0.2.3
     , streaming-commons >=0.2
     , time >=1.8
-    , unix >=2.7
   default-language: Haskell2010
   if flag(static)
     ghc-options: -optl-static
diff --git a/src/Config.hs b/src/Config.hs
--- a/src/Config.hs
+++ b/src/Config.hs
@@ -34,8 +34,7 @@
 import Paths_dprox
 
 data GlobalConfig = GlobalConfig
-    { setUser       :: Maybe String
-    , localPort     :: Maybe PortNumber
+    { localPort     :: Maybe PortNumber
     , listenAddress :: Maybe HostPreference
     , cacheSize     :: Int
     , cacheTTL      :: DNS.TTL
@@ -171,8 +170,7 @@
 invalidIPAddress = "::"
 
 globalOption :: Parser GlobalConfig
-globalOption = GlobalConfig <$> userOption
-                            <*> portOption
+globalOption = GlobalConfig <$> portOption
                             <*> listenOption
                             <*> cacheOption
                             <*> ttlOption
@@ -180,12 +178,6 @@
                             <*> ipsetMatchOption
                             <*> ipsetServerOption
   where
-    userOption = optional $ strOption
-        ( long "user"
-       <> short 'u'
-       <> metavar "<username>"
-       <> help "Specify the userid to which dprox will change after startup")
-
     portOption = optional $ option auto
         ( long "port"
        <> short 'p'
diff --git a/src/Main.hs b/src/Main.hs
--- a/src/Main.hs
+++ b/src/Main.hs
@@ -21,8 +21,6 @@
 import Data.Version              (showVersion)
 import Network.DNS               qualified as DNS
 import Network.Socket.ByteString (recvFrom, sendTo)
-import System.Posix.User
-    (UserEntry (..), getUserEntryForName, setUserID)
 
 import Config
 import DomainRoute
@@ -161,9 +159,6 @@
                             return (Right (ttl, v))
     return process
 
-setuid :: String -> IO ()
-setuid user = getUserEntryForName user >>= setUserID . userID
-
 main :: IO ()
 main = getConfig >>= \(GlobalConfig{..}, conf) -> withLogger (LogStdout 4096) loglevel $ \logger -> do
     logger INFO $ "dprox " <> toLogStr (showVersion version) <> " started"
@@ -214,8 +209,6 @@
         logger INFO $ "creating resolver: " <> toLogStr (show $ fst k) <> ":" <> toLogStr (show $ snd k)
         rs <- DNS.makeResolvSeed v
         return (k, rs)
-
-    F.mapM_ setuid setUser
 
     resolverCache <- makeResolverCache cacheSize cacheTTL
     ipsetCache <- newCache 4096 maxBound