diff --git a/system/fwupd/fwupd.SlackBuild b/system/fwupd/fwupd.SlackBuild
index cc3383c16c..30a6de9755 100644
--- a/system/fwupd/fwupd.SlackBuild
+++ b/system/fwupd/fwupd.SlackBuild
@@ -87,8 +87,9 @@ meson --prefix=/usr \
   -Dplugin_uefi=false \
   build
 
-ninja -C build
-DESTDIR=$PKG ninja -C build install
+"${NINJA:=ninja}"
+$NINJA -C build
+DESTDIR=$PKG $NINJA -C build install
 
 find $PKG -print0 | xargs -0 file | grep -e "executable" -e "shared object" | grep ELF \
   | cut -f 1 -d : | xargs strip --strip-unneeded 2> /dev/null || true