diff --git a/run.sh b/run.sh
index 0b04297..ae72481 100755
--- a/run.sh
+++ b/run.sh
@@ -1,7 +1,11 @@
 #!/usr/bin/env bash
 
 help () {
-  echo 'dchr-run <chroot-dir> [command]'
+  echo 'dchr-run [options] <chroot-dir> [command]'
+  echo '-- options:'
+  echo '   -u uid[:gid]  invoke command in chroot as a different user'
+  # TODO:
+  #echo '   -x11          apply options for correctly starting GUI apps'
   echo 'https://dchr.dc09.ru'
 }
 
@@ -28,22 +32,43 @@ setup () {
 
 runcmd () {
   echo -e '-- \e[1;32mOK\e[0m -- running chroot'
-  chrdir="$1"
-  shift
+  userspec="--userspec=$1"
+  chrdir="$2"
+  shift 2
   chrcmd=("$@")
-  chroot "$chrdir" "${chrcmd[@]}"
+  chroot "$userspec" "$chrdir" "${chrcmd[@]}"
 }
 
 main () {
   [[ "$1" == "--help" || "$1" == "" ]] && help && exit 0
 
+  userspec="$(id -u):$(id -g)"
+
+  while [[ "$1" == -* ]]
+  do
+    case "$1" in
+      -u)
+        userspec="$2"
+        shift 2
+        ;;
+      #-x11);; TODO
+      *)
+        echo -ne '-- \e[1mInvalid option:\e[0m '
+        echo "$1"
+        echo '-- Use ./ or full path if your chroot-dir starts with dash (-)'
+        help
+        exit 2
+        ;;
+    esac
+  done
+
   chrdir=$(readlink -f "$1")
   shift
 
   trap "clean \"$chrdir\"" EXIT
 
   setup "$chrdir"
-  runcmd "$chrdir" "$@"
+  runcmd "$userspec" "$chrdir" "$@"
   exit $?
 }