diff --git a/run.sh b/run.sh
index 2bc2f3da19a100782815ba2d950002a5d1ea3045..5a544baf37452b68a1e530bfb6c3335e88cfa5f1 100755
--- a/run.sh
+++ b/run.sh
@@ -10,6 +10,14 @@ else
     echo "Number of iterations is niter=$ITERATIONS."
 fi
 
+if [ ! -v NOFAST ]
+then
+    echo "Use fast option (with use_dll)."
+    NOFAST=false
+else
+    echo "Do not use fast option (with use_dll)"
+fi
+
 if [ ! -v DYNARE ]
 then
     echo "Path to dynare must be provided."
@@ -38,7 +46,7 @@ do
     then
         while [ ! -f $model-done.info ]
         do
-            matlab -batch "addpath $DYNARE; addpath $WHEREAMI/matlab; MODEL='$model'; niter=$ITERATIONS; run_all_simulations;" |& tee -a $model-all.log
+            matlab -batch "addpath $DYNARE; addpath $WHEREAMI/matlab; MODEL='$model'; niter=$ITERATIONS; nofast=$NOFAST; run_all_simulations;" |& tee -a $model-all.log
         done
         printf " \u2714 $model\n"
     else