diff --git a/conf/clear.cfg b/conf/clear.cfg
index 299b040..566cd83 100644
--- a/conf/clear.cfg
+++ b/conf/clear.cfg
@@ -6,6 +6,8 @@ config_opts['dist'] = 'clear'  # only useful for --resultdir variable subst
 config_opts['extra_chroot_dirs'] = [ '/run/lock', ]
 config_opts['useradd'] = '/usr/sbin/useradd -m -u %(uid)s -g %(gid)s -d %(home)s  %(user)s'
 config_opts['plugin_conf']['ccache_enable'] = False
+config_opts['plugin_conf']['root_cache_opts']['compress_program'] = 'zstd -5'
+config_opts['plugin_conf']['root_cache_opts']['extension'] = '.zst'
 config_opts['releasever'] = 'clear'
 config_opts['package_manager'] = 'dnf'
 config_opts['chrootgroup'] = 'mockbuild'