diff --git a/helper/build_config b/helper/build_config
index 525ddf87..a029ce27 100755
--- a/helper/build_config
+++ b/helper/build_config
@@ -7,9 +7,13 @@
 set -e
 set -u
 
-if [ "${#:-}" -ne 1 ] ; then
-  echo "Usage: /usr/share/ngcp-ngcpcfg/helper/build_config <input_file>" >&2
+usage() {
+  echo "Usage: /usr/share/ngcp-ngcpcfg/helper/build_config [--reuse <file>] <input_file>" >&2
   exit 1
+}
+
+if [ "${#:-}" -lt 1 ] ; then
+  usage
 fi
 
 # support for testsuite, assume defaults if unset
@@ -21,6 +25,20 @@ HELPER="${HELPER:-/usr/share/ngcp-ngcpcfg/helper/}"
 
 # main script
 
+if [ -n "${1:-}" ] ; then
+  case "$1" in
+    *--reuse*)
+      shift
+      if [ -z "${1:-}" ] ; then
+	usage
+      else
+        TT_WRAPER_ARGS="--reuse $1"
+	shift
+      fi
+      ;;
+  esac
+fi
+
 input_file="$1"       # like /etc/ngcp-config/templates/etc/mysql/my.cnf.tt2
 # calculate output file {{{
   x=${input_file##${NGCPCTL_MAIN}/templates/}     # drop leading /etc/ngcp-config
@@ -58,8 +76,8 @@ umask 0077
 TT_WRAPPER="${HELPER}/tt2-wrapper"
 
 log_debug "Output file ${output_file} based on ${input_file}"
-log_debug "Executing: $TT_WRAPPER ${input_file} ${host_conf:-} ${local_conf:-} $NGCPCTL_CONFIG ${NETWORK_CONFIG:-} ${EXTRA_CONFIG_FILES:-} $CONSTANTS_CONFIG > ${output_file}"
-if "$TT_WRAPPER" "${input_file}" ${host_conf:-} ${local_conf:-} "$NGCPCTL_CONFIG" "${NETWORK_CONFIG:-}" ${EXTRA_CONFIG_FILES:-} "$CONSTANTS_CONFIG" > "${output_file}" 2>/dev/null ; then
+log_debug "Executing: $TT_WRAPPER ${TT_WRAPER_ARGS:-} ${input_file} ${host_conf:-} ${local_conf:-} $NGCPCTL_CONFIG ${NETWORK_CONFIG:-} ${EXTRA_CONFIG_FILES:-} $CONSTANTS_CONFIG > ${output_file}"
+if "$TT_WRAPPER" ${TT_WRAPER_ARGS:-} "${input_file}" ${host_conf:-} ${local_conf:-} "$NGCPCTL_CONFIG" "${NETWORK_CONFIG:-}" ${EXTRA_CONFIG_FILES:-} "$CONSTANTS_CONFIG" > "${output_file}" 2>/dev/null ; then
   log_info "Generating ${output_file}: OK"
   RC=0
 else
diff --git a/helper/tt2-wrapper b/helper/tt2-wrapper
index 99849a17..1c6eb8d4 100755
--- a/helper/tt2-wrapper
+++ b/helper/tt2-wrapper
@@ -5,16 +5,39 @@
 use strict;
 use warnings;
 
-use YAML qw/LoadFile/;
-use Template;
+use Getopt::Long;
 use Hash::Merge qw(merge);
+use Storable;
+use Template;
+use YAML qw/LoadFile/;
+
+my $help;
+my $reuse;
+
+GetOptions(
+    'help'    => \$help,
+    'reuse=s' => \$reuse,
+) or die "Usage: $0 [--reuse <file>] <template> <config.yml> [<another.yml>]";
 
 my $tt = Template->new({ ABSOLUTE => 1, RELATIVE => 1, EVAL_PERL => 1 });
-my $template = shift(@ARGV);
+my $template = shift(@ARGV) or die "Usage: $0 [--reuse <file>] <template> <config.yml> [<another.yml>]";
 
 my $config = {};
-foreach my $file (@ARGV) {
-  $config = merge($config, LoadFile($file) || die $!);
+
+if ($reuse) {
+  if (-e $reuse) {
+    $config = retrieve($reuse);
+  } else {
+    foreach my $file (@ARGV) {
+      $config = merge($config, LoadFile($file) || die $!);
+    }
+
+    store($config, $reuse);
+  }
+} else {
+  foreach my $file (@ARGV) {
+    $config = merge($config, LoadFile($file) || die $!);
+  }
 }
 
 # NOTE: we can't rely on "$tt->process($template, $config)" because the config
diff --git a/scripts/build b/scripts/build
index 9580ec74..33862a0a 100755
--- a/scripts/build
+++ b/scripts/build
@@ -24,6 +24,13 @@ if [ -n "${1:-}" ] ; then
   esac
 fi
 
+if [ -n "${NO_REUSE:-}" ] ; then
+  log_info "Not using --reuse feature of tt2-wrapper as requested via NO_REUSE"
+else
+  tmpfile=$(mktemp --dry-run --tmpdir=/tmp/ ngcpcfgreuse.XXXXXX)
+  BUILD_CONFIG_ARGS="--reuse ${tmpfile}"
+fi
+
 # make sure encoding is OK
 for f in ${NGCPCTL_CONFIG:-} ${HOST_CONFIG:-} ${LOCAL_CONFIG:-} ${NETWORK_CONFIG:-} ${EXTRA_CONFIG_FILES:-} ${CONSTANTS_CONFIG:-} ; do
   if [ -r "$f" ] && ! file "$f" | grep -qe "UTF-8" -qe "ASCII" ; then
@@ -54,8 +61,8 @@ done
 
 build_config_files() {
   for file in $(generate_template_list $*) ; do
-    log_debug "${HELPER}/build_config $file"
-    "${HELPER}/build_config" "${file}"
+    log_debug "${HELPER}/build_config ${BUILD_CONFIG_ARGS:-} $file"
+    "${HELPER}/build_config" ${BUILD_CONFIG_ARGS:-} "${file}"
     RC=$(($RC + $?))
   done
 }
@@ -136,6 +143,14 @@ else
   fi
 fi
 
+if [ -z "${NO_REUSE:-}" ] ; then
+  if [ -n "${DEBUG:-}" ] ; then
+    log_debug "Not removing temporary rerun file ${tmpfile} since we are in debug mode"
+  else
+    rm -f "${tmpfile}"
+  fi
+fi
+
 exit "$RC"
 
 ## END OF FILE #################################################################