diff --git a/etc/guix-install.sh b/etc/guix-install.sh
index 2944cb97f6a..68e96166a4c 100755
--- a/etc/guix-install.sh
+++ b/etc/guix-install.sh
@@ -51,6 +51,8 @@
 # installation required the user to extract Guix packs under /gnu to
 # satisfy its dependencies.
 
+# shellcheck shell=bash
+
 # shellcheck disable=2268 # try to support vintage shells
 if [ "x$BASH_VERSION" = "x" ]; then
     exec bash "$0" "$@"
@@ -510,7 +512,7 @@ sys_create_build_user()
 	fi
 
 	create_account guix-daemon guix-daemon		\
-		       guix-daemon$KVMGROUP		\
+		       guix-daemon"$KVMGROUP"		\
 		       "Unprivileged Guix Daemon User"
 
 	# ‘tar xf’ creates root:root files.  Change that.