diff --git a/scripts/install-multi-user.sh b/scripts/install-multi-user.sh
index 19f787ab5..b65e08682 100644
--- a/scripts/install-multi-user.sh
+++ b/scripts/install-multi-user.sh
@@ -56,6 +56,9 @@ readonly NIX_INSTALLED_CACERT="@cacert@"
 #readonly NIX_INSTALLED_CACERT="/nix/store/7dxhzymvy330i28ii676fl1pqwcahv2f-nss-cacert-3.49.2"
 readonly EXTRACTED_NIX_PATH="$(dirname "$0")"
 
+# allow to override identity change command
+readonly NIX_BECOME=${NIX_BECOME:-sudo}
+
 readonly ROOT_HOME=~root
 
 if [ -t 0 ] && [ -z "${NIX_INSTALLER_YES:-}" ]; then
@@ -123,7 +126,7 @@ uninstall_directions() {
             cat <<EOF
 $step. Restore $profile_target$PROFILE_BACKUP_SUFFIX back to $profile_target
 
-  sudo mv $profile_target$PROFILE_BACKUP_SUFFIX $profile_target
+  $NIX_BECOME mv $profile_target$PROFILE_BACKUP_SUFFIX $profile_target
 
 (after this one, you may need to re-open any terminals that were
 opened while it existed.)
@@ -136,7 +139,7 @@ EOF
     cat <<EOF
 $step. Delete the files Nix added to your system:
 
-  sudo rm -rf "/etc/nix" "$NIX_ROOT" "$ROOT_HOME/.nix-profile" "$ROOT_HOME/.nix-defexpr" "$ROOT_HOME/.nix-channels" "$ROOT_HOME/.local/state/nix" "$ROOT_HOME/.cache/nix" "$HOME/.nix-profile" "$HOME/.nix-defexpr" "$HOME/.nix-channels" "$HOME/.local/state/nix" "$HOME/.cache/nix"
+  $NIX_BECOME rm -rf "/etc/nix" "$NIX_ROOT" "$ROOT_HOME/.nix-profile" "$ROOT_HOME/.nix-defexpr" "$ROOT_HOME/.nix-channels" "$ROOT_HOME/.local/state/nix" "$ROOT_HOME/.cache/nix" "$HOME/.nix-profile" "$HOME/.nix-defexpr" "$HOME/.nix-channels" "$HOME/.local/state/nix" "$HOME/.cache/nix"
 
 and that is it.
 
@@ -343,7 +346,7 @@ __sudo() {
 
     echo "I am executing:"
     echo ""
-    printf "    $ sudo %s\\n" "$cmd"
+    printf "    $ $NIX_BECOME %s\\n" "$cmd"
     echo ""
     echo "$expl"
     echo ""
@@ -361,7 +364,9 @@ _sudo() {
     if is_root; then
         env "$@"
     else
-        sudo "$@"
+        # env sets environment variables for sudo alternatives
+        # that don't support "VAR=value command" syntax
+        $NIX_BECOME env "$@"
     fi
 }
 
diff --git a/scripts/install-nix-from-tarball.sh b/scripts/install-nix-from-tarball.sh
index 007fe85ee..8d127a9c5 100644
--- a/scripts/install-nix-from-tarball.sh
+++ b/scripts/install-nix-from-tarball.sh
@@ -9,6 +9,8 @@ self="$(dirname "$0")"
 nix="@nix@"
 cacert="@cacert@"
 
+# allow to override identity change command
+readonly NIX_BECOME="${NIX_BECOME:-sudo}"
 
 if ! [ -e "$self/.reginfo" ]; then
     echo "$0: incomplete installer (.reginfo is missing)" >&2
@@ -63,7 +65,6 @@ while [ $# -gt 0 ]; do
                 exit 1
             fi
             INSTALL_MODE=no-daemon
-            # intentional tail space
             ACTION=install
             ;;
         --yes)
@@ -135,8 +136,8 @@ echo "performing a single-user installation of Nix..." >&2
 
 if ! [ -e "$dest" ]; then
     cmd="mkdir -m 0755 $dest && chown $USER $dest"
-    echo "directory $dest does not exist; creating it by running '$cmd' using sudo" >&2
-    if ! sudo sh -c "$cmd"; then
+    echo "directory $dest does not exist; creating it by running '$cmd' using $NIX_BECOME" >&2
+    if ! $NIX_BECOME sh -c "$cmd"; then
         echo "$0: please manually run '$cmd' as root to create $dest" >&2
         exit 1
     fi