diff --git a/releng/README.releng b/releng/README.releng
index 74ff4484..aa05908d 100644
--- a/releng/README.releng
+++ b/releng/README.releng
@@ -14,6 +14,7 @@ Release Engineering Che[at|ck] List
 * DELIVERING A NEW TEST SCRIPT
  + start a new test over the top of template_new_releng
  + file name starts with releng_
+ + any generated data to be stored in ./$0.result directory
  + mandatory options -rc [-clean]
  + well documented configuration file test.conf{.template}
  + throw FAIL string to stdout if any failure is detected
diff --git a/releng/releng_build_isojigdo b/releng/releng_build_isojigdo
index 4bd0503f..5b57bf41 100755
--- a/releng/releng_build_isojigdo
+++ b/releng/releng_build_isojigdo
@@ -13,7 +13,7 @@ ISOLINUX_BIN=""
 BOOT_CAT=""
 CONFFILE=$HOME/releng_build_isojigdo.conf
 CLEAN=0
-
+GEN_DATA_DIR=$0.result
 RES=""
 
 print_help() {
@@ -28,6 +28,12 @@ HLP
 }
 
 #####################################################################
+if [ -d "${GEN_DATA_DIR}" ]; then
+ printf "\n$0: %s exists!\n" ${GEN_DATA_DIR}
+ exit 2
+else
+ mkdir "${GEN_DATA_DIR}"
+fi
 # help
 if [ ! "${1}" ]; then print_help && exit 10; fi
 # config file
@@ -90,7 +96,7 @@ fi
 # create MD5 list in base64 format
 if which jigdo-gen-md5-list >/dev/null 2>&1; then
  printf "$0: Creating MD5 list in hex format..."
- jigdo-gen-md5-list ${DIR} > ${IMG}.md5
+ jigdo-gen-md5-list ${DIR} > ${GEN_DATA_DIR}/${IMG}.md5
  printf "Done.\n"
 else
  printf "\n$0: Not found: jigdo-gen-md5-list. Install jigit."
@@ -102,7 +108,7 @@ fi
 CMD="${XOR} \
  -as mkisofs \
  -quiet \
- -o ${IMG}.iso \
+ -o ${GEN_DATA_DIR}/${IMG}.iso \
  -R \
  -V ISOJIGDO \
  -partition_offset 16 \
@@ -125,10 +131,10 @@ CMD+="\
  -jigdo-template-compress gzip \
  -checksum_algorithm_iso md5,sha1,sha256,sha512 \
  -checksum_algorithm_template md5,sha1,sha256,sha512 \
- -jigdo-jigdo ${IMG}.jigdo \
- -jigdo-template ${IMG}.template \
+ -jigdo-jigdo ${GEN_DATA_DIR}/${IMG}.jigdo \
+ -jigdo-template ${GEN_DATA_DIR}/${IMG}.template \
  -jigdo-map Debian=${DIR} \
- -md5-list  ${IMG}.md5 \
+ -md5-list  ${GEN_DATA_DIR}/${IMG}.md5 \
  -jigdo-min-file-size 1024 \
 "
 
@@ -142,10 +148,10 @@ ${CMD}
 if which jigit-mkimage >/dev/null 2>&1; then
  printf "$0: Creating new ISO from jigdo files..."
  jigit-mkimage \
-  -t ${IMG}.template \
-  -j ${IMG}.jigdo \
+  -t ${GEN_DATA_DIR}/${IMG}.template \
+  -j ${GEN_DATA_DIR}/${IMG}.jigdo \
   -m Debian=${DIR} \
-  -o ${IMG}.new
+  -o ${GEN_DATA_DIR}/${IMG}.new
  printf "Done.\n"
 else
  printf "\n$0: Not found: jigit-mkimage. Install jigit."
@@ -154,11 +160,11 @@ else
 fi
 
 # trap the exit code of diff and let the Universe explode
-diff ${IMG}.iso ${IMG}.new
+diff ${GEN_DATA_DIR}/${IMG}.iso ${GEN_DATA_DIR}/${IMG}.new
 DIFF_RET="$?"
 case ${DIFF_RET} in
      0)
-      echo -e "$0: diff ${IMG}.iso ${IMG}.new matched.\n"
+      echo -e "$0: diff ${GEN_DATA_DIR}/${IMG}.iso ${GEN_DATA_DIR}/${IMG}.new matched.\n"
      ;;
      *)
       echo -e "$0: FAIL: diff returned code: $DIFF_RET\n"
@@ -170,10 +176,10 @@ if [ ${CLEAN} -eq 1 ]; then
  # safety net, just in case -> we want to be in the starting
  # directory before removing whatever self-generated stuff
  cd "${START_DIR_DONT_CHANGE}" || exit 80
- rm -f ${RES}
- printf "$0: removed %s\n" ${RES}
+ rm -rf ${GEN_DATA_DIR}
+ printf "$0: removed %s\n" ${GEN_DATA_DIR}
 else
- printf "$0: left %s\n" ${RES}
+ printf "$0: left %s\n" ${GEN_DATA_DIR}
 fi
 
 # last hints