diff --git a/run.sh b/run.sh
index 991b9f174f543cb691dc22b1c1a670fd8a748a4f..dba9c8c812c7f223d521c1f0ffc7fd808cd9a53d 100755
--- a/run.sh
+++ b/run.sh
@@ -30,6 +30,10 @@ function check-cepcsw-envvar() {
 function build-dir() {
     local blddir=build
 
+    if [ -n "${bldtool}" ]; then
+        blddir=${blddir}.${bldtool}
+    fi
+
     # If detect the extra env var, append it to the build dir
     if [ -n "${lcg_version}" ]; then
         blddir=${blddir}.${lcg_version}
@@ -65,6 +69,8 @@ function run-job() {
 lcg_platform=x86_64-centos7-gcc8-opt
 lcg_version=98.0.0
 
+bldtool=${CEPCSW_BLDTOOL} # make, ninja # set in env var
+
 check-cepcsw-envvar || exit -1
 
 check-working-builddir || exit -1