diff --git a/lib/functions.bash b/lib/functions.bash
index 0d328f3..2d7c857 100644
--- a/lib/functions.bash
+++ b/lib/functions.bash
@@ -7,10 +7,22 @@ function assert_root {
   true
 }
 
+function assert_container {
+  cat /proc/self/cgroup | awk -F / '{print $NF}' | grep -qE '^(session-c|\.lxc)'
+}
+
 function assert_system_mode {
-  [[ -L "$MIAOU_BASH_DIR" ]] && >&2 echo "ERROR: development mode: $(realpath $MIAOU_BASH_DIR)" && return 3
+  [[ -L "$MIAOU_BASH_DIR" ]] &&
+    >&2 echo "ERROR: development mode: $(realpath "$MIAOU_BASH_DIR")" &&
+    return 3
+
+  assert_container && [[ ! -w $MIAOU_BASH_DIR ]] &&
+    >&2 echo "ERROR: hosted mode" &&
+    return 4
+
   true
 }
+
 ## ===============
 ## ARRAY Functions
 ## ===============
diff --git a/lib/self-upgrade.bash b/lib/self-upgrade.bash
index 2b913bf..ae7b97d 100755
--- a/lib/self-upgrade.bash
+++ b/lib/self-upgrade.bash
@@ -11,6 +11,7 @@ function self_upgrade {
   mv "$MIAOU_BASH_DIR" "$MIAOU_BASH_DIR".before_upgrade
   "$MIAOU_BASH_DIR".before_upgrade/install.sh upgraded
   rm -rf "$MIAOU_BASH_DIR".before_upgrade
+  echo -n "version: "
   . "$MIAOU_BASH_DIR"/bin/miaou-bash --version
 }