diff --git a/tools/build.sh b/tools/build.sh
new file mode 100755
index 00000000000..29224e992dd
--- /dev/null
+++ b/tools/build.sh
@@ -0,0 +1,171 @@
+#!/usr/bin/env bash
+# tools/build.sh
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+function cleanup()
+{
+  # keep the mapping but change to the link since:
+  # 1.root can't access mount point created by normal user
+  # 2.debugger could find the source code without manual setting
+  fusermount -u ${MOUNTDIR}
+  rmdir ${MOUNTDIR}
+  ln -s ${ROOTDIR} ${MOUNTDIR}
+}
+
+function mount_unionfs()
+{
+  echo -e "Mount command line:"
+  echo -e "  unionfs-fuse -o cow ${OUTDIR}=RW:${ROOTDIR}=RO ${MOUNTDIR}"
+
+  rm -f ${MOUNTDIR}
+  mkdir -p ${MOUNTDIR}
+  unionfs-fuse -o cow ${OUTDIR}=RW:${ROOTDIR}=RO ${MOUNTDIR}
+}
+
+function build_board()
+{
+  echo -e "Build command line:"
+  echo -e "  ${TOOLSDIR}/configure.sh -e $*"
+  echo -e "  make -C ${NUTTXDIR} EXTRAFLAGS=-Wno-cpp ${@:2}"
+  echo -e "  make -C ${NUTTXDIR} savedefconfig"
+
+  if [ ! -f "${ROOTDIR}/prebuilts/kconfig-frontends/bin/kconfig-conf" ]; then
+    pushd ${ROOTDIR}/prebuilts/kconfig-frontends
+    ./configure --prefix=${ROOTDIR}/prebuilts/kconfig-frontends 1>/dev/null
+    touch aclocal.m4 Makefile.in
+    make install 1>/dev/null
+    popd
+  fi
+  export PATH=${ROOTDIR}/prebuilts/kconfig-frontends/bin:$PATH
+
+  if ! ${TOOLSDIR}/configure.sh -e $*; then
+    echo "Error: ############# config ${1} fail ##############"
+    exit 1
+  fi
+
+  ARCH=`sed -n 's/CONFIG_ARCH="\(.*\)"/\1/p' ${NUTTXDIR}/.config`
+  export PATH=${ROOTDIR}/prebuilts/gcc/linux/$ARCH/bin:$PATH
+
+  if ! make -C ${NUTTXDIR} EXTRAFLAGS=-Wno-cpp ${@:2}; then
+    echo "Error: ############# build ${1} fail ##############"
+    exit 2
+  fi
+
+  if [ "${2}" = "distclean" ]; then
+    return;
+  fi
+
+   if ! make -C ${NUTTXDIR} savedefconfig; then
+    echo "Error: ############# save ${1} fail ##############"
+    exit 3
+  fi
+  cp ${NUTTXDIR}/defconfig ${ROOTDIR}/nuttx/boards/*/*/${1/[:|\/]//configs/}
+}
+
+function pack_sdk()
+{
+  VENDOR=(\
+      "realtek" \
+      "allwinner" )
+  BOARDS=(\
+      "
+      amebaZ
+      " \
+      "
+      perf1-r328
+      " \
+      )
+
+  if [ "${2}" != "export" ]; then
+    exit 0
+  fi
+
+  if [ ! -f $OUTDIR/nuttx/.version ]; then
+    exit 1
+  fi
+
+  source $OUTDIR/nuttx/.version
+
+  local exportzip=$OUTDIR/nuttx/nuttx-export-$CONFIG_VERSION_STRING.zip
+
+  echo $exportzip
+  if [ ! -f $exportzip ]; then
+    exit 1
+  fi
+
+  local version=$CONFIG_VERSION_STRING.$CONFIG_VERSION_BUILD
+  local packname=`echo nuttx-sdk-$1-$version.zip | sed 's/\//-/g'`
+  local board=`echo $1 | awk -F '[:|\/]' '{print $1}'`
+  local vendor=
+
+  for (( i = 0; i < ${#BOARDS[*]}; i++)); do
+    if [ $board == ${BOARDS[$i]} ]; then
+      vendor=vendor/${VENDOR[$i]}
+      break
+    fi
+  done
+
+  cp $exportzip .
+  zip -r $packname sdk $vendor `basename $exportzip` -x "sdk/.git*" 1>/dev/null 2>&1
+
+  if [ $? -eq 0 ]; then
+    echo "############## Export SDK Success: $packname ##############"
+  fi
+
+  rm `basename $exportzip`
+}
+
+if [ $# == 0 ]; then
+  echo "Usage: $0 [-m] <board-name>:<config-name> [make options]"
+  echo ""
+  echo "Where:"
+  echo "  -m: out of tree build. Or default in tree build without it."
+  exit 1
+fi
+
+ROOTDIR=$(dirname $(readlink -f ${0}))
+ROOTDIR=$(realpath ${ROOTDIR}/../..)
+
+if [ $1 == "-m" ]; then
+  # out of tree build
+  configdir=`echo ${2} | cut -s -d':' -f2`
+  if [ -z "${configdir}" ]; then
+    boarddir=`echo ${2} | rev | cut -d'/' -f3 | rev`
+    configdir=`echo ${2} | rev | cut -d'/' -f1 | rev`
+    if [ -z "${configdir}" ]; then
+      boarddir=`echo ${2} | rev | cut -d'/' -f4 | rev`
+      configdir=`echo ${2} | rev | cut -d'/' -f2 | rev`
+    fi
+  else
+    boarddir=`echo ${2} | cut -d':' -f1`
+  fi
+
+  OUTDIR=${ROOTDIR}/out/${boarddir}/${configdir}
+  MOUNTDIR=${OUTDIR}/.unionfs
+  NUTTXDIR=${MOUNTDIR}/nuttx
+
+  trap cleanup EXIT
+  mount_unionfs
+  shift
+else
+  # in tree build
+  OUTDIR=${ROOTDIR}
+  NUTTXDIR=${ROOTDIR}/nuttx
+fi
+
+TOOLSDIR=${NUTTXDIR}/tools
+
+build_board $*
+pack_sdk $*