diff --git a/speechx/examples/README.md b/speechx/examples/README.md
index b18c88e0..1b977523 100644
--- a/speechx/examples/README.md
+++ b/speechx/examples/README.md
@@ -22,14 +22,7 @@ netron exp/deepspeech2_online/checkpoints/avg_1.jit.pdmodel  --port 8022 --host
 
 ## For Developer  
 
-> Warning: Only for developer, make sure you know what's it.
+> Reminder: Only for developer, make sure you know what's it.
 
-* dev - for speechx developer, using for test.
+* codelab - for speechx developer, using for test.
 
-## Build WFST  
-
-> Warning: Using below example when you know what's it.
-
-* text_lm - process text for build lm
-* ngram - using to build NGram ARPA lm.
-* wfst - build wfst for TLG.
diff --git a/speechx/examples/codelab/README.md b/speechx/examples/codelab/README.md
new file mode 100644
index 00000000..f89184de
--- /dev/null
+++ b/speechx/examples/codelab/README.md
@@ -0,0 +1,8 @@
+# Codelab
+
+## introduction
+
+> The below is for developing and offline testing. Do not run it only if you know what it is.
+* nnet
+* feat
+* decoder
diff --git a/speechx/examples/ds2_ol/decoder/.gitignore b/speechx/examples/codelab/decoder/.gitignore
similarity index 100%
rename from speechx/examples/ds2_ol/decoder/.gitignore
rename to speechx/examples/codelab/decoder/.gitignore
diff --git a/speechx/examples/ds2_ol/decoder/README.md b/speechx/examples/codelab/decoder/README.md
similarity index 100%
rename from speechx/examples/ds2_ol/decoder/README.md
rename to speechx/examples/codelab/decoder/README.md
diff --git a/speechx/examples/codelab/decoder/path.sh b/speechx/examples/codelab/decoder/path.sh
new file mode 100644
index 00000000..9d229174
--- /dev/null
+++ b/speechx/examples/codelab/decoder/path.sh
@@ -0,0 +1,14 @@
+# This contains the locations of binarys build required for running the examples.
+
+SPEECHX_ROOT=$PWD/../../../
+SPEECHX_BUILD=$SPEECHX_ROOT/build/speechx
+
+SPEECHX_TOOLS=$SPEECHX_ROOT/tools
+TOOLS_BIN=$SPEECHX_TOOLS/valgrind/install/bin
+
+[ -d $SPEECHX_BUILD ] || { echo "Error: 'build/speechx' directory not found. please ensure that the project build successfully"; }
+
+export LC_AL=C
+
+SPEECHX_BIN=$SPEECHX_ROOT/build/speechx/decoder:$SPEECHX_ROOT/build/speechx/frontend/audio
+export PATH=$PATH:$SPEECHX_BIN:$TOOLS_BIN
diff --git a/speechx/examples/ds2_ol/decoder/run.sh b/speechx/examples/codelab/decoder/run.sh
similarity index 94%
rename from speechx/examples/ds2_ol/decoder/run.sh
rename to speechx/examples/codelab/decoder/run.sh
index 40501eb4..a911eb03 100755
--- a/speechx/examples/ds2_ol/decoder/run.sh
+++ b/speechx/examples/codelab/decoder/run.sh
@@ -54,7 +54,7 @@ cmvn=$exp_dir/cmvn.ark
 export GLOG_logtostderr=1
 
 # dump json cmvn to kaldi
-cmvn-json2kaldi \
+cmvn_json2kaldi_main \
     --json_file  $ckpt_dir/data/mean_std.json \
     --cmvn_write_path $cmvn \
     --binary=false
@@ -62,17 +62,17 @@ echo "convert json cmvn to kaldi ark."
 
 
 # generate linear feature as streaming
-linear-spectrogram-wo-db-norm-ol \
+compute_linear_spectrogram_main \
     --wav_rspecifier=scp:$data/wav.scp \
     --feature_wspecifier=ark,t:$feat_wspecifier \
     --cmvn_file=$cmvn
 echo "compute linear spectrogram feature."
 
 # run ctc beam search decoder as streaming
-ctc-prefix-beam-search-decoder-ol \
+ctc_prefix_beam_search_decoder_main \
     --result_wspecifier=ark,t:$exp_dir/result.txt \
     --feature_rspecifier=ark:$feat_wspecifier \
     --model_path=$model_dir/avg_1.jit.pdmodel \
     --param_path=$model_dir/avg_1.jit.pdiparams \
     --dict_file=$vocb_dir/vocab.txt \
-    --lm_path=$lm
\ No newline at end of file
+    --lm_path=$lm
diff --git a/speechx/examples/ds2_ol/decoder/valgrind.sh b/speechx/examples/codelab/decoder/valgrind.sh
similarity index 100%
rename from speechx/examples/ds2_ol/decoder/valgrind.sh
rename to speechx/examples/codelab/decoder/valgrind.sh
diff --git a/speechx/examples/ds2_ol/feat/README.md b/speechx/examples/codelab/feat/README.md
similarity index 58%
rename from speechx/examples/ds2_ol/feat/README.md
rename to speechx/examples/codelab/feat/README.md
index 89cb79ec..e59e02bf 100644
--- a/speechx/examples/ds2_ol/feat/README.md
+++ b/speechx/examples/codelab/feat/README.md
@@ -2,6 +2,6 @@
 
 ASR audio feature test bins. We using theses bins to test linaer/fbank/mfcc asr feature as streaming manner.
 
-* linear_spectrogram_without_db_norm_main.cc
+* compute_linear_spectrogram_main.cc
 
-compute linear spectrogram w/o db norm in streaming manner.
+compute linear spectrogram without db norm in streaming manner.
diff --git a/speechx/examples/ds2_ol/decoder/path.sh b/speechx/examples/codelab/feat/path.sh
similarity index 82%
rename from speechx/examples/ds2_ol/decoder/path.sh
rename to speechx/examples/codelab/feat/path.sh
index 8e26e6e7..3b89d01e 100644
--- a/speechx/examples/ds2_ol/decoder/path.sh
+++ b/speechx/examples/codelab/feat/path.sh
@@ -10,5 +10,5 @@ TOOLS_BIN=$SPEECHX_TOOLS/valgrind/install/bin
 
 export LC_AL=C
 
-SPEECHX_BIN=$SPEECHX_EXAMPLES/ds2_ol/decoder:$SPEECHX_EXAMPLES/ds2_ol/feat
+SPEECHX_BIN=$SPEECHX_ROOT/build/speechx/decoder:$SPEECHX_ROOT/build/speechx/frontend/audio
 export PATH=$PATH:$SPEECHX_BIN:$TOOLS_BIN
diff --git a/speechx/examples/ds2_ol/feat/run.sh b/speechx/examples/codelab/feat/run.sh
similarity index 95%
rename from speechx/examples/ds2_ol/feat/run.sh
rename to speechx/examples/codelab/feat/run.sh
index 75777927..1fa37f98 100755
--- a/speechx/examples/ds2_ol/feat/run.sh
+++ b/speechx/examples/codelab/feat/run.sh
@@ -41,14 +41,14 @@ mkdir -p $exp_dir
 # 3. run feat
 export GLOG_logtostderr=1
 
-cmvn-json2kaldi \
+cmvn_json2kaldi_main \
     --json_file  $model_dir/data/mean_std.json \
     --cmvn_write_path $exp_dir/cmvn.ark \
     --binary=false
 echo "convert json cmvn to kaldi ark."
 
 
-linear-spectrogram-wo-db-norm-ol \
+compute_linear_spectrogram_main \
     --wav_rspecifier=scp:$data_dir/wav.scp \
     --feature_wspecifier=ark,t:$exp_dir/feats.ark \
     --cmvn_file=$exp_dir/cmvn.ark
diff --git a/speechx/examples/ds2_ol/feat/valgrind.sh b/speechx/examples/codelab/feat/valgrind.sh
similarity index 93%
rename from speechx/examples/ds2_ol/feat/valgrind.sh
rename to speechx/examples/codelab/feat/valgrind.sh
index f8aab63f..ea50fdc2 100755
--- a/speechx/examples/ds2_ol/feat/valgrind.sh
+++ b/speechx/examples/codelab/feat/valgrind.sh
@@ -17,7 +17,7 @@ feat_wspecifier=./feats.ark
 cmvn=./cmvn.ark
 
 valgrind --tool=memcheck --track-origins=yes --leak-check=full --show-leak-kinds=all \
-  linear_spectrogram_main \
+  compute_linear_spectrogram_main \
   --wav_rspecifier=scp:$model_dir/wav.scp \
   --feature_wspecifier=ark,t:$feat_wspecifier \
   --cmvn_write_path=$cmvn
diff --git a/speechx/examples/ds2_ol/nnet/.gitignore b/speechx/examples/codelab/nnet/.gitignore
similarity index 100%
rename from speechx/examples/ds2_ol/nnet/.gitignore
rename to speechx/examples/codelab/nnet/.gitignore
diff --git a/speechx/examples/ds2_ol/nnet/README.md b/speechx/examples/codelab/nnet/README.md
similarity index 100%
rename from speechx/examples/ds2_ol/nnet/README.md
rename to speechx/examples/codelab/nnet/README.md
diff --git a/speechx/examples/ds2_ol/nnet/path.sh b/speechx/examples/codelab/nnet/path.sh
similarity index 81%
rename from speechx/examples/ds2_ol/nnet/path.sh
rename to speechx/examples/codelab/nnet/path.sh
index 0ee8b478..7d395d64 100644
--- a/speechx/examples/ds2_ol/nnet/path.sh
+++ b/speechx/examples/codelab/nnet/path.sh
@@ -1,7 +1,7 @@
 # This contains the locations of binarys build required for running the examples.
 
 SPEECHX_ROOT=$PWD/../../../
-SPEECHX_EXAMPLES=$SPEECHX_ROOT/build/examples
+SPEECHX_BUILD=$SPEECHX_ROOT/build/speechx
 
 SPEECHX_TOOLS=$SPEECHX_ROOT/tools
 TOOLS_BIN=$SPEECHX_TOOLS/valgrind/install/bin
@@ -10,5 +10,5 @@ TOOLS_BIN=$SPEECHX_TOOLS/valgrind/install/bin
 
 export LC_AL=C
 
-SPEECHX_BIN=$SPEECHX_EXAMPLES/ds2_ol/nnet
+SPEECHX_BIN=$SPEECHX_BUILD/codelab/nnet
 export PATH=$PATH:$SPEECHX_BIN:$TOOLS_BIN
diff --git a/speechx/examples/ds2_ol/nnet/run.sh b/speechx/examples/codelab/nnet/run.sh
similarity index 75%
rename from speechx/examples/ds2_ol/nnet/run.sh
rename to speechx/examples/codelab/nnet/run.sh
index 10029f7e..842499ba 100755
--- a/speechx/examples/ds2_ol/nnet/run.sh
+++ b/speechx/examples/codelab/nnet/run.sh
@@ -20,19 +20,10 @@ if [ ! -f data/model/asr0_deepspeech2_online_aishell_ckpt_0.2.0.model.tar.gz ];
     popd
 fi
 
-# produce wav scp
-if [ ! -f data/wav.scp ]; then
-    mkdir -p data
-    pushd data
-    wget -c https://paddlespeech.bj.bcebos.com/PaddleAudio/zh.wav
-    echo "utt1 " $PWD/zh.wav > wav.scp
-    popd 
-fi
-
 ckpt_dir=./data/model
 model_dir=$ckpt_dir/exp/deepspeech2_online/checkpoints/
 
-ds2-model-ol-test \
+ds2_model_test_main \
     --model_path=$model_dir/avg_1.jit.pdmodel \
     --param_path=$model_dir/avg_1.jit.pdiparams
 
diff --git a/speechx/examples/ds2_ol/nnet/valgrind.sh b/speechx/examples/codelab/nnet/valgrind.sh
similarity index 71%
rename from speechx/examples/ds2_ol/nnet/valgrind.sh
rename to speechx/examples/codelab/nnet/valgrind.sh
index 2a08c608..a5aab663 100755
--- a/speechx/examples/ds2_ol/nnet/valgrind.sh
+++ b/speechx/examples/codelab/nnet/valgrind.sh
@@ -12,9 +12,10 @@ if [ ! -d ${SPEECHX_TOOLS}/valgrind/install ]; then
   exit 1
 fi
 
-model_dir=../paddle_asr_model
+ckpt_dir=./data/model
+model_dir=$ckpt_dir/exp/deepspeech2_online/checkpoints/
 
 valgrind --tool=memcheck --track-origins=yes --leak-check=full --show-leak-kinds=all \
-  pp-model-test \
+  ds2_model_test_main \
   --model_path=$model_dir/avg_1.jit.pdmodel \
-  --param_path=$model_dir/avg_1.jit.pdparams
\ No newline at end of file
+  --param_path=$model_dir/avg_1.jit.pdparams
diff --git a/speechx/examples/custom_asr/run.sh b/speechx/examples/custom_asr/run.sh
index 8d88000d..dddcf9fd 100644
--- a/speechx/examples/custom_asr/run.sh
+++ b/speechx/examples/custom_asr/run.sh
@@ -7,7 +7,7 @@ export GLOG_logtostderr=1
 . ./path.sh || exit 1;
 
 # ds2 means deepspeech2 (acoutic model type)
-dir=$PWD/ds2_graph_with_slot
+dir=$PWD/exp/ds2_graph_with_slot
 data=$PWD/data
 stage=0
 stop_stage=10
@@ -80,9 +80,9 @@ if [ ${stage} -le 4 ] && [ ${stop_stage} -ge 4 ]; then
     --word_symbol_table=$graph/words.txt \
     --graph_path=$graph/TLG.fst --max_active=7500 \
     --acoustic_scale=12 \
-    --result_wspecifier=ark,t:./result_run.txt
+    --result_wspecifier=ark,t:./exp/result_run.txt
 
     # the data/wav.trans is the label.
-    utils/compute-wer.py --char=1 --v=1 data/wav.trans result_run.txt > wer_run
-    tail -n 7 wer_run
+    utils/compute-wer.py --char=1 --v=1 data/wav.trans exp/result_run.txt > exp/wer_run
+    tail -n 7 exp/wer_run
 fi
diff --git a/speechx/examples/ds2_ol/CMakeLists.txt b/speechx/examples/ds2_ol/CMakeLists.txt
deleted file mode 100644
index 08c19484..00000000
--- a/speechx/examples/ds2_ol/CMakeLists.txt
+++ /dev/null
@@ -1,6 +0,0 @@
-cmake_minimum_required(VERSION 3.14 FATAL_ERROR)
-
-add_subdirectory(feat)
-add_subdirectory(nnet)
-add_subdirectory(decoder)
-add_subdirectory(websocket)
diff --git a/speechx/examples/ds2_ol/aishell/local/text_to_lexicon.py b/speechx/examples/ds2_ol/aishell/local/text_to_lexicon.py
deleted file mode 100755
index ba5ab60a..00000000
--- a/speechx/examples/ds2_ol/aishell/local/text_to_lexicon.py
+++ /dev/null
@@ -1,37 +0,0 @@
-#!/usr/bin/env python3
-import argparse
-from collections import Counter
-
-
-def main(args):
-    counter = Counter()
-    with open(args.text, 'r') as fin, open(args.lexicon, 'w') as fout:
-        for line in fin:
-            line = line.strip()
-            if args.has_key:
-                utt, text = line.split(maxsplit=1)
-                words = text.split()
-            else:
-                words = line.split()
-
-            counter.update(words)
-
-        for word in counter:
-            val = " ".join(list(word))
-            fout.write(f"{word}\t{val}\n")
-            fout.flush()
-
-
-if __name__ == '__main__':
-    parser = argparse.ArgumentParser(
-        description='text(line:utt1 中国 人) to lexicon（line:中国 中 国).')
-    parser.add_argument(
-        '--has_key', default=True, help='text path, with utt or not')
-    parser.add_argument(
-        '--text', required=True, help='text path. line: utt1 中国 人 or 中国 人')
-    parser.add_argument(
-        '--lexicon', required=True, help='lexicon path. line:中国 中 国')
-    args = parser.parse_args()
-    print(args)
-
-    main(args)
diff --git a/speechx/examples/ds2_ol/aishell/path.sh b/speechx/examples/ds2_ol/aishell/path.sh
index 1807a277..69c78e74 100755
--- a/speechx/examples/ds2_ol/aishell/path.sh
+++ b/speechx/examples/ds2_ol/aishell/path.sh
@@ -1,13 +1,13 @@
 # This contains the locations of binarys build required for running the examples.
 
 MAIN_ROOT=`realpath $PWD/../../../../`
-SPEECHX_ROOT=$PWD/../../..
-SPEECHX_EXAMPLES=$SPEECHX_ROOT/build/examples
+SPEECHX_ROOT=$PWD/../../../
+SPEECHX_BUILD=$SPEECHX_ROOT/build/speechx
 
 SPEECHX_TOOLS=$SPEECHX_ROOT/tools
 TOOLS_BIN=$SPEECHX_TOOLS/valgrind/install/bin
 
-[ -d $SPEECHX_EXAMPLES ] || { echo "Error: 'build/examples' directory not found. please ensure that the project build successfully"; }
+[ -d $SPEECHX_BUILD ] || { echo "Error: 'build/speechx' directory not found. please ensure that the project build successfully"; }
 
 export LC_AL=C
 
@@ -20,5 +20,5 @@ export LIBLBFGS=${MAIN_ROOT}/tools/liblbfgs-1.10
 export LD_LIBRARY_PATH=${LD_LIBRARY_PATH:-}:${LIBLBFGS}/lib/.libs
 export SRILM=${MAIN_ROOT}/tools/srilm
 
-SPEECHX_BIN=$SPEECHX_EXAMPLES/ds2_ol/decoder:$SPEECHX_EXAMPLES/ds2_ol/feat:$SPEECHX_EXAMPLES/ds2_ol/websocket
+SPEECHX_BIN=$SPEECHX_BUILD/decoder:$SPEECHX_BUILD/frontend/audio:$SPEECHX_BUILD/websocket
 export PATH=$PATH:$SPEECHX_BIN:$TOOLS_BIN:${SRILM}/bin:${SRILM}/bin/i686-m64:$KALDI_DIR/lmbin:$KALDI_DIR/fstbin:$OPENFST_DIR/bin
diff --git a/speechx/examples/ds2_ol/aishell/run.sh b/speechx/examples/ds2_ol/aishell/run.sh
index 650cb140..e1001e25 100755
--- a/speechx/examples/ds2_ol/aishell/run.sh
+++ b/speechx/examples/ds2_ol/aishell/run.sh
@@ -69,12 +69,12 @@ export GLOG_logtostderr=1
 cmvn=$data/cmvn.ark
 if [ ${stage} -le 1 ] && [ ${stop_stage} -ge 1 ]; then
     # 3. gen linear feat
-    cmvn-json2kaldi --json_file=$ckpt_dir/data/mean_std.json --cmvn_write_path=$cmvn
+    cmvn_json2kaldi_main --json_file=$ckpt_dir/data/mean_std.json --cmvn_write_path=$cmvn
 
     ./local/split_data.sh $data $data/$aishell_wav_scp $aishell_wav_scp $nj
 
     utils/run.pl JOB=1:$nj $data/split${nj}/JOB/feat.log \
-    linear-spectrogram-wo-db-norm-ol \
+    compute_linear_spectrogram_main \
         --wav_rspecifier=scp:$data/split${nj}/JOB/${aishell_wav_scp} \
         --feature_wspecifier=ark,scp:$data/split${nj}/JOB/feat.ark,$data/split${nj}/JOB/feat.scp \
         --cmvn_file=$cmvn \
@@ -85,7 +85,7 @@ fi
 if [ ${stage} -le 2 ] && [ ${stop_stage} -ge 2 ]; then
     #  recognizer
     utils/run.pl JOB=1:$nj $data/split${nj}/JOB/recog.wolm.log \
-    ctc-prefix-beam-search-decoder-ol \
+    ctc_prefix_beam_search_decoder_main \
         --feature_rspecifier=scp:$data/split${nj}/JOB/feat.scp \
         --model_path=$model_dir/avg_1.jit.pdmodel \
         --param_path=$model_dir/avg_1.jit.pdiparams \
@@ -102,7 +102,7 @@ fi
 if [ ${stage} -le 3 ] && [ ${stop_stage} -ge 3 ]; then
     #  decode with lm
     utils/run.pl JOB=1:$nj $data/split${nj}/JOB/recog.lm.log \
-    ctc-prefix-beam-search-decoder-ol \
+    ctc_prefix_beam_search_decoder_main \
         --feature_rspecifier=scp:$data/split${nj}/JOB/feat.scp \
         --model_path=$model_dir/avg_1.jit.pdmodel \
         --param_path=$model_dir/avg_1.jit.pdiparams \
@@ -132,7 +132,7 @@ fi
 if [ ${stage} -le 4 ] && [ ${stop_stage} -ge 4 ]; then
     #  TLG decoder
     utils/run.pl JOB=1:$nj $data/split${nj}/JOB/recog.wfst.log \
-    wfst-decoder-ol \
+    tlg_decoder_main \
         --feature_rspecifier=scp:$data/split${nj}/JOB/feat.scp \
         --model_path=$model_dir/avg_1.jit.pdmodel \
         --param_path=$model_dir/avg_1.jit.pdiparams \
@@ -151,7 +151,7 @@ fi
 if [ ${stage} -le 5 ] && [ ${stop_stage} -ge 5 ]; then
     #  TLG decoder
     utils/run.pl JOB=1:$nj $data/split${nj}/JOB/recognizer.log \
-    recognizer_test_main \
+    recognizer_main \
         --wav_rspecifier=scp:$data/split${nj}/JOB/${aishell_wav_scp} \
         --cmvn_file=$cmvn \
         --model_path=$model_dir/avg_1.jit.pdmodel \
diff --git a/speechx/examples/ds2_ol/aishell/run_build_tlg.sh b/speechx/examples/ds2_ol/aishell/run_build_tlg.sh
index 4394ac5a..2e148657 100755
--- a/speechx/examples/ds2_ol/aishell/run_build_tlg.sh
+++ b/speechx/examples/ds2_ol/aishell/run_build_tlg.sh
@@ -118,7 +118,7 @@ export GLOG_logtostderr=1
 if [ ${stage} -le 4 ] && [ ${stop_stage} -ge 4 ]; then
     #  TLG decoder
     utils/run.pl JOB=1:$nj $data/split${nj}/JOB/check_tlg.log \
-    recognizer_test_main \
+    recognizer_main \
         --wav_rspecifier=scp:$data/split${nj}/JOB/${aishell_wav_scp} \
         --cmvn_file=$cmvn \
         --model_path=$model_dir/avg_5.jit.pdmodel \
diff --git a/speechx/examples/ds2_ol/aishell/run_fbank.sh b/speechx/examples/ds2_ol/aishell/run_fbank.sh
index 483fbfdf..6e131677 100755
--- a/speechx/examples/ds2_ol/aishell/run_fbank.sh
+++ b/speechx/examples/ds2_ol/aishell/run_fbank.sh
@@ -69,7 +69,7 @@ export GLOG_logtostderr=1
 cmvn=$data/cmvn_fbank.ark
 if [ ${stage} -le 1 ] && [ ${stop_stage} -ge 1 ]; then
     # 3. gen linear feat
-    cmvn-json2kaldi --json_file=$ckpt_dir/data/mean_std.json --cmvn_write_path=$cmvn --binary=false
+    cmvn_json2kaldi_main --json_file=$ckpt_dir/data/mean_std.json --cmvn_write_path=$cmvn --binary=false
 
     ./local/split_data.sh $data $data/$aishell_wav_scp $aishell_wav_scp $nj
 
@@ -84,7 +84,7 @@ fi
 if [ ${stage} -le 2 ] && [ ${stop_stage} -ge 2 ]; then
     #  recognizer
     utils/run.pl JOB=1:$nj $data/split${nj}/JOB/recog.fbank.wolm.log \
-    ctc-prefix-beam-search-decoder-ol \
+    ctc_prefix_beam_search_decoder_main \
         --feature_rspecifier=scp:$data/split${nj}/JOB/fbank_feat.scp \
         --model_path=$model_dir/avg_5.jit.pdmodel \
         --param_path=$model_dir/avg_5.jit.pdiparams \
@@ -100,12 +100,12 @@ fi
 if [ ${stage} -le 3 ] && [ ${stop_stage} -ge 3 ]; then
     #  decode with lm
     utils/run.pl JOB=1:$nj $data/split${nj}/JOB/recog.fbank.lm.log \
-    ctc-prefix-beam-search-decoder-ol \
+    ctc_prefix_beam_search_decoder_main \
         --feature_rspecifier=scp:$data/split${nj}/JOB/fbank_feat.scp \
         --model_path=$model_dir/avg_5.jit.pdmodel \
         --param_path=$model_dir/avg_5.jit.pdiparams \
         --model_output_names=softmax_0.tmp_0,tmp_5,concat_0.tmp_0,concat_1.tmp_0 \
-	--model_cache_shapes="5-1-2048,5-1-2048" \
+	    --model_cache_shapes="5-1-2048,5-1-2048" \
         --dict_file=$vocb_dir/vocab.txt \
         --lm_path=$lm \
         --result_wspecifier=ark,t:$data/split${nj}/JOB/fbank_result_lm
@@ -129,13 +129,13 @@ fi
 if [ ${stage} -le 4 ] && [ ${stop_stage} -ge 4 ]; then
     #  TLG decoder
     utils/run.pl JOB=1:$nj $data/split${nj}/JOB/recog.fbank.wfst.log \
-    wfst-decoder-ol \
+    tlg_decoder_main \
         --feature_rspecifier=scp:$data/split${nj}/JOB/fbank_feat.scp \
         --model_path=$model_dir/avg_5.jit.pdmodel \
         --param_path=$model_dir/avg_5.jit.pdiparams \
         --word_symbol_table=$wfst/words.txt \
         --model_output_names=softmax_0.tmp_0,tmp_5,concat_0.tmp_0,concat_1.tmp_0 \
-	--model_cache_shapes="5-1-2048,5-1-2048" \
+	    --model_cache_shapes="5-1-2048,5-1-2048" \
         --graph_path=$wfst/TLG.fst --max_active=7500 \
         --acoustic_scale=1.2 \
         --result_wspecifier=ark,t:$data/split${nj}/JOB/result_tlg
@@ -148,7 +148,7 @@ fi
 
 if [ ${stage} -le 5 ] && [ ${stop_stage} -ge 5 ]; then
     utils/run.pl JOB=1:$nj $data/split${nj}/JOB/fbank_recognizer.log \
-    recognizer_test_main \
+    recognizer_main \
         --wav_rspecifier=scp:$data/split${nj}/JOB/${aishell_wav_scp} \
         --cmvn_file=$cmvn \
         --model_path=$model_dir/avg_5.jit.pdmodel \
diff --git a/speechx/examples/ds2_ol/decoder/CMakeLists.txt b/speechx/examples/ds2_ol/decoder/CMakeLists.txt
deleted file mode 100644
index 62dd6862..00000000
--- a/speechx/examples/ds2_ol/decoder/CMakeLists.txt
+++ /dev/null
@@ -1,22 +0,0 @@
-cmake_minimum_required(VERSION 3.14 FATAL_ERROR)
-
-set(bin_name ctc-prefix-beam-search-decoder-ol)
-add_executable(${bin_name} ${CMAKE_CURRENT_SOURCE_DIR}/${bin_name}.cc)
-target_include_directories(${bin_name} PRIVATE ${SPEECHX_ROOT} ${SPEECHX_ROOT}/kaldi)
-target_link_libraries(${bin_name} PUBLIC nnet decoder fst utils gflags glog kaldi-base kaldi-matrix kaldi-util ${DEPS})
-
-
-set(bin_name wfst-decoder-ol)
-add_executable(${bin_name} ${CMAKE_CURRENT_SOURCE_DIR}/${bin_name}.cc)
-target_include_directories(${bin_name} PRIVATE ${SPEECHX_ROOT} ${SPEECHX_ROOT}/kaldi)
-target_link_libraries(${bin_name} PUBLIC nnet decoder fst utils gflags glog kaldi-base kaldi-matrix kaldi-util kaldi-decoder ${DEPS})
-
-
-set(bin_name nnet-logprob-decoder-test)
-add_executable(${bin_name} ${CMAKE_CURRENT_SOURCE_DIR}/${bin_name}.cc)
-target_include_directories(${bin_name} PRIVATE ${SPEECHX_ROOT} ${SPEECHX_ROOT}/kaldi)
-target_link_libraries(${bin_name} PUBLIC nnet decoder fst utils gflags glog kaldi-base kaldi-matrix kaldi-util ${DEPS})
-
-add_executable(recognizer_test_main ${CMAKE_CURRENT_SOURCE_DIR}/recognizer_test_main.cc)
-target_include_directories(recognizer_test_main PRIVATE ${SPEECHX_ROOT} ${SPEECHX_ROOT}/kaldi)
-target_link_libraries(recognizer_test_main PUBLIC frontend kaldi-feat-common nnet decoder fst utils gflags glog kaldi-base kaldi-matrix kaldi-util kaldi-decoder ${DEPS})
diff --git a/speechx/examples/ds2_ol/decoder/local/model.sh b/speechx/examples/ds2_ol/decoder/local/model.sh
deleted file mode 100644
index 5c609a6c..00000000
--- a/speechx/examples/ds2_ol/decoder/local/model.sh
+++ /dev/null
@@ -1,3 +0,0 @@
-#!/bin/bash 
-
-
diff --git a/speechx/examples/ds2_ol/feat/.gitignore b/speechx/examples/ds2_ol/feat/.gitignore
deleted file mode 100644
index 566f2d97..00000000
--- a/speechx/examples/ds2_ol/feat/.gitignore
+++ /dev/null
@@ -1,2 +0,0 @@
-exp
-data
diff --git a/speechx/examples/ds2_ol/feat/CMakeLists.txt b/speechx/examples/ds2_ol/feat/CMakeLists.txt
deleted file mode 100644
index 632f22e8..00000000
--- a/speechx/examples/ds2_ol/feat/CMakeLists.txt
+++ /dev/null
@@ -1,16 +0,0 @@
-cmake_minimum_required(VERSION 3.14 FATAL_ERROR)
-
-set(bin_name linear-spectrogram-wo-db-norm-ol)
-add_executable(${bin_name} ${CMAKE_CURRENT_SOURCE_DIR}/${bin_name}.cc)
-target_include_directories(${bin_name} PRIVATE ${SPEECHX_ROOT} ${SPEECHX_ROOT}/kaldi)
-target_link_libraries(${bin_name} frontend kaldi-util kaldi-feat-common gflags glog)
-
-set(bin_name compute_fbank_main)
-add_executable(${bin_name} ${CMAKE_CURRENT_SOURCE_DIR}/${bin_name}.cc)
-target_include_directories(${bin_name} PRIVATE ${SPEECHX_ROOT} ${SPEECHX_ROOT}/kaldi)
-target_link_libraries(${bin_name} frontend kaldi-util kaldi-feat-common gflags glog)
-
-set(bin_name cmvn-json2kaldi)
-add_executable(${bin_name} ${CMAKE_CURRENT_SOURCE_DIR}/${bin_name}.cc)
-target_include_directories(${bin_name} PRIVATE ${SPEECHX_ROOT} ${SPEECHX_ROOT}/kaldi)
-target_link_libraries(${bin_name} utils kaldi-util kaldi-matrix gflags glog)
diff --git a/speechx/examples/ds2_ol/feat/path.sh b/speechx/examples/ds2_ol/feat/path.sh
deleted file mode 100644
index ad2b6a4e..00000000
--- a/speechx/examples/ds2_ol/feat/path.sh
+++ /dev/null
@@ -1,14 +0,0 @@
-# This contains the locations of binarys build required for running the examples.
-
-SPEECHX_ROOT=$PWD/../../../
-SPEECHX_EXAMPLES=$SPEECHX_ROOT/build/examples
-
-SPEECHX_TOOLS=$SPEECHX_ROOT/tools
-TOOLS_BIN=$SPEECHX_TOOLS/valgrind/install/bin
-
-[ -d $SPEECHX_EXAMPLES ] || { echo "Error: 'build/examples' directory not found. please ensure that the project build successfully"; }
-
-export LC_AL=C
-
-SPEECHX_BIN=$SPEECHX_EXAMPLES/ds2_ol/feat
-export PATH=$PATH:$SPEECHX_BIN:$TOOLS_BIN
diff --git a/speechx/examples/ds2_ol/websocket/CMakeLists.txt b/speechx/examples/ds2_ol/websocket/CMakeLists.txt
deleted file mode 100644
index ed542aad..00000000
--- a/speechx/examples/ds2_ol/websocket/CMakeLists.txt
+++ /dev/null
@@ -1,9 +0,0 @@
-cmake_minimum_required(VERSION 3.14 FATAL_ERROR)
-
-add_executable(websocket_server_main ${CMAKE_CURRENT_SOURCE_DIR}/websocket_server_main.cc)
-target_include_directories(websocket_server_main PRIVATE ${SPEECHX_ROOT} ${SPEECHX_ROOT}/kaldi)
-target_link_libraries(websocket_server_main PUBLIC frontend kaldi-feat-common nnet decoder fst utils gflags glog kaldi-base kaldi-matrix kaldi-util kaldi-decoder websocket ${DEPS})
-
-add_executable(websocket_client_main ${CMAKE_CURRENT_SOURCE_DIR}/websocket_client_main.cc)
-target_include_directories(websocket_client_main PRIVATE ${SPEECHX_ROOT} ${SPEECHX_ROOT}/kaldi)
-target_link_libraries(websocket_client_main PUBLIC frontend kaldi-feat-common nnet decoder fst utils gflags glog kaldi-base kaldi-matrix kaldi-util kaldi-decoder websocket ${DEPS})
\ No newline at end of file
diff --git a/speechx/examples/ds2_ol/websocket/path.sh b/speechx/examples/ds2_ol/websocket/path.sh
index d66b5dcc..3ad03203 100755
--- a/speechx/examples/ds2_ol/websocket/path.sh
+++ b/speechx/examples/ds2_ol/websocket/path.sh
@@ -1,14 +1,14 @@
 # This contains the locations of binarys build required for running the examples.
 
-SPEECHX_ROOT=$PWD/../../..
-SPEECHX_EXAMPLES=$SPEECHX_ROOT/build/examples
+SPEECHX_ROOT=$PWD/../../../
+SPEECHX_BUILD=$SPEECHX_ROOT/build/speechx
 
 SPEECHX_TOOLS=$SPEECHX_ROOT/tools
 TOOLS_BIN=$SPEECHX_TOOLS/valgrind/install/bin
 
-[ -d $SPEECHX_EXAMPLES ] || { echo "Error: 'build/examples' directory not found. please ensure that the project build successfully"; }
+[ -d $SPEECHX_BUILD ] || { echo "Error: 'build/speechx' directory not found. please ensure that the project build successfully"; }
 
 export LC_AL=C
 
-SPEECHX_BIN=$SPEECHX_EXAMPLES/ds2_ol/websocket:$SPEECHX_EXAMPLES/ds2_ol/feat
+SPEECHX_BIN=$SPEECHX_BUILD/websocket
 export PATH=$PATH:$SPEECHX_BIN:$TOOLS_BIN
diff --git a/speechx/speechx/CMakeLists.txt b/speechx/speechx/CMakeLists.txt
index b4da095d..a9a8a398 100644
--- a/speechx/speechx/CMakeLists.txt
+++ b/speechx/speechx/CMakeLists.txt
@@ -37,3 +37,9 @@ ${CMAKE_CURRENT_SOURCE_DIR}
 ${CMAKE_CURRENT_SOURCE_DIR}/websocket
 )
 add_subdirectory(websocket)
+
+include_directories(
+${CMAKE_CURRENT_SOURCE_DIR}
+${CMAKE_CURRENT_SOURCE_DIR}/codelab
+)
+add_subdirectory(codelab)
diff --git a/speechx/examples/CMakeLists.txt b/speechx/speechx/codelab/CMakeLists.txt
similarity index 52%
rename from speechx/examples/CMakeLists.txt
rename to speechx/speechx/codelab/CMakeLists.txt
index bcb23edd..95043263 100644
--- a/speechx/examples/CMakeLists.txt
+++ b/speechx/speechx/codelab/CMakeLists.txt
@@ -1,3 +1,4 @@
 cmake_minimum_required(VERSION 3.14 FATAL_ERROR)
 
-add_subdirectory(ds2_ol)
+add_subdirectory(glog)
+add_subdirectory(nnet)
diff --git a/speechx/speechx/codelab/README.md b/speechx/speechx/codelab/README.md
new file mode 100644
index 00000000..aee60de6
--- /dev/null
+++ b/speechx/speechx/codelab/README.md
@@ -0,0 +1,7 @@
+
+## For Developer  
+
+> Reminder: Only for developer.
+
+* codelab - for speechx developer, using for test.
+
diff --git a/speechx/speechx/codelab/glog/CMakeLists.txt b/speechx/speechx/codelab/glog/CMakeLists.txt
new file mode 100644
index 00000000..08a98641
--- /dev/null
+++ b/speechx/speechx/codelab/glog/CMakeLists.txt
@@ -0,0 +1,8 @@
+cmake_minimum_required(VERSION 3.14 FATAL_ERROR)
+
+add_executable(glog_main ${CMAKE_CURRENT_SOURCE_DIR}/glog_main.cc)
+target_link_libraries(glog_main glog)
+
+
+add_executable(glog_logtostderr_main ${CMAKE_CURRENT_SOURCE_DIR}/glog_logtostderr_main.cc)
+target_link_libraries(glog_logtostderr_main glog)
diff --git a/speechx/speechx/codelab/glog/README.md b/speechx/speechx/codelab/glog/README.md
new file mode 100644
index 00000000..3282c920
--- /dev/null
+++ b/speechx/speechx/codelab/glog/README.md
@@ -0,0 +1,38 @@
+# [GLOG](https://rpg.ifi.uzh.ch/docs/glog.html)
+
+Unless otherwise specified, glog writes to the filename `/tmp/<program name>.<hostname>.<user name>.log.<severity level>.<date>.<time>.<pid>` (e.g., "/tmp/hello_world.example.com.hamaji.log.INFO.20080709-222411.10474"). By default, glog copies the log messages of severity level ERROR or FATAL to standard error (stderr) in addition to log files.
+
+Several flags influence glog's output behavior. If the Google gflags library is installed on your machine, the configure script (see the INSTALL file in the package for detail of this script) will automatically detect and use it, allowing you to pass flags on the command line. For example, if you want to turn the flag --logtostderr on, you can start your application with the following command line:
+
+   `./your_application --logtostderr=1`
+
+If the Google gflags library isn't installed, you set flags via environment variables, prefixing the flag name with "GLOG_", e.g.
+
+   `GLOG_logtostderr=1 ./your_application`
+
+You can also modify flag values in your program by modifying global variables `FLAGS_*` . Most settings start working immediately after you update `FLAGS_*` . The exceptions are the flags related to destination files. For example, you might want to set `FLAGS_log_dir` before calling `google::InitGoogleLogging` . Here is an example:
+∂∂
+```c++
+   LOG(INFO) << "file";
+   // Most flags work immediately after updating values.
+   FLAGS_logtostderr = 1;
+   LOG(INFO) << "stderr";
+   FLAGS_logtostderr = 0;
+   // This won't change the log destination. If you want to set this
+   // value, you should do this before google::InitGoogleLogging .
+   FLAGS_log_dir = "/some/log/directory";
+   LOG(INFO) << "the same file";
+```
+
+* this is the test script:
+```
+# run 
+glog_test
+
+echo "------"
+export FLAGS_logtostderr=1 
+glog_test
+
+echo "------"
+glog_logtostderr_test
+```
diff --git a/speechx/speechx/codelab/glog/glog_logtostderr_main.cc b/speechx/speechx/codelab/glog/glog_logtostderr_main.cc
new file mode 100644
index 00000000..b0616a7d
--- /dev/null
+++ b/speechx/speechx/codelab/glog/glog_logtostderr_main.cc
@@ -0,0 +1,25 @@
+// Copyright (c) 2022 PaddlePaddle Authors. All Rights Reserved.
+//
+// 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.
+
+#include <glog/logging.h>
+
+int main(int argc, char* argv[]) {
+    // Initialize Google’s logging library.
+    google::InitGoogleLogging(argv[0]);
+
+    FLAGS_logtostderr = 1;
+
+    LOG(INFO) << "Found " << 10 << " cookies";
+    LOG(ERROR) << "Found " << 10 << " error";
+}
\ No newline at end of file
diff --git a/speechx/speechx/codelab/glog/glog_main.cc b/speechx/speechx/codelab/glog/glog_main.cc
new file mode 100644
index 00000000..b6275119
--- /dev/null
+++ b/speechx/speechx/codelab/glog/glog_main.cc
@@ -0,0 +1,23 @@
+// Copyright (c) 2022 PaddlePaddle Authors. All Rights Reserved.
+//
+// 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.
+
+#include <glog/logging.h>
+
+int main(int argc, char* argv[]) {
+    // Initialize Google’s logging library.
+    google::InitGoogleLogging(argv[0]);
+
+    LOG(INFO) << "Found " << 10 << " cookies";
+    LOG(ERROR) << "Found " << 10 << " error";
+}
\ No newline at end of file
diff --git a/speechx/examples/ds2_ol/nnet/CMakeLists.txt b/speechx/speechx/codelab/nnet/CMakeLists.txt
similarity index 87%
rename from speechx/examples/ds2_ol/nnet/CMakeLists.txt
rename to speechx/speechx/codelab/nnet/CMakeLists.txt
index 6745a51a..dcad8a9c 100644
--- a/speechx/examples/ds2_ol/nnet/CMakeLists.txt
+++ b/speechx/speechx/codelab/nnet/CMakeLists.txt
@@ -1,6 +1,6 @@
 cmake_minimum_required(VERSION 3.14 FATAL_ERROR)
 
-set(bin_name ds2-model-ol-test)
+set(bin_name ds2_model_test_main)
 add_executable(${bin_name} ${CMAKE_CURRENT_SOURCE_DIR}/${bin_name}.cc)
 target_include_directories(${bin_name} PRIVATE ${SPEECHX_ROOT} ${SPEECHX_ROOT}/kaldi)
-target_link_libraries(${bin_name} PUBLIC nnet gflags glog ${DEPS})
\ No newline at end of file
+target_link_libraries(${bin_name} PUBLIC nnet gflags glog ${DEPS})
diff --git a/speechx/examples/ds2_ol/nnet/ds2-model-ol-test.cc b/speechx/speechx/codelab/nnet/ds2_model_test_main.cc
similarity index 100%
rename from speechx/examples/ds2_ol/nnet/ds2-model-ol-test.cc
rename to speechx/speechx/codelab/nnet/ds2_model_test_main.cc
diff --git a/speechx/speechx/decoder/CMakeLists.txt b/speechx/speechx/decoder/CMakeLists.txt
index 06bf4020..1df93511 100644
--- a/speechx/speechx/decoder/CMakeLists.txt
+++ b/speechx/speechx/decoder/CMakeLists.txt
@@ -10,3 +10,16 @@ add_library(decoder STATIC
   recognizer.cc
 )
 target_link_libraries(decoder PUBLIC kenlm utils fst frontend nnet kaldi-decoder)
+
+set(BINS 
+  ctc_prefix_beam_search_decoder_main
+  nnet_logprob_decoder_main
+  recognizer_main
+  tlg_decoder_main
+)
+
+foreach(bin_name IN LISTS BINS)
+  add_executable(${bin_name} ${CMAKE_CURRENT_SOURCE_DIR}/${bin_name}.cc)
+  target_include_directories(${bin_name} PRIVATE ${SPEECHX_ROOT} ${SPEECHX_ROOT}/kaldi)
+  target_link_libraries(${bin_name} PUBLIC nnet decoder fst utils gflags glog kaldi-base kaldi-matrix kaldi-util ${DEPS})
+endforeach()
diff --git a/speechx/examples/ds2_ol/decoder/ctc-prefix-beam-search-decoder-ol.cc b/speechx/speechx/decoder/ctc_prefix_beam_search_decoder_main.cc
similarity index 100%
rename from speechx/examples/ds2_ol/decoder/ctc-prefix-beam-search-decoder-ol.cc
rename to speechx/speechx/decoder/ctc_prefix_beam_search_decoder_main.cc
diff --git a/speechx/examples/ds2_ol/decoder/nnet-logprob-decoder-test.cc b/speechx/speechx/decoder/nnet_logprob_decoder_main.cc
similarity index 100%
rename from speechx/examples/ds2_ol/decoder/nnet-logprob-decoder-test.cc
rename to speechx/speechx/decoder/nnet_logprob_decoder_main.cc
diff --git a/speechx/examples/ds2_ol/decoder/recognizer_test_main.cc b/speechx/speechx/decoder/recognizer_main.cc
similarity index 100%
rename from speechx/examples/ds2_ol/decoder/recognizer_test_main.cc
rename to speechx/speechx/decoder/recognizer_main.cc
diff --git a/speechx/examples/ds2_ol/decoder/wfst-decoder-ol.cc b/speechx/speechx/decoder/tlg_decoder_main.cc
similarity index 100%
rename from speechx/examples/ds2_ol/decoder/wfst-decoder-ol.cc
rename to speechx/speechx/decoder/tlg_decoder_main.cc
diff --git a/speechx/speechx/frontend/audio/CMakeLists.txt b/speechx/speechx/frontend/audio/CMakeLists.txt
index 745832fe..0aec68fa 100644
--- a/speechx/speechx/frontend/audio/CMakeLists.txt
+++ b/speechx/speechx/frontend/audio/CMakeLists.txt
@@ -9,5 +9,22 @@ add_library(frontend STATIC
   feature_pipeline.cc
   fbank.cc
 )
-
 target_link_libraries(frontend PUBLIC kaldi-matrix kaldi-feat-common kaldi-fbank)
+
+
+
+set(bin_name cmvn_json2kaldi_main)
+add_executable(${bin_name} ${CMAKE_CURRENT_SOURCE_DIR}/${bin_name}.cc)
+target_include_directories(${bin_name} PRIVATE ${SPEECHX_ROOT} ${SPEECHX_ROOT}/kaldi)
+target_link_libraries(${bin_name} utils kaldi-util kaldi-matrix gflags glog)
+
+set(BINS 
+  compute_linear_spectrogram_main
+  compute_fbank_main
+)
+
+foreach(bin_name IN LISTS BINS)
+  add_executable(${bin_name} ${CMAKE_CURRENT_SOURCE_DIR}/${bin_name}.cc)
+  target_include_directories(${bin_name} PRIVATE ${SPEECHX_ROOT} ${SPEECHX_ROOT}/kaldi)
+  target_link_libraries(${bin_name} PUBLIC frontend utils kaldi-util gflags glog)
+endforeach()
\ No newline at end of file
diff --git a/speechx/examples/ds2_ol/feat/cmvn-json2kaldi.cc b/speechx/speechx/frontend/audio/cmvn_json2kaldi_main.cc
similarity index 100%
rename from speechx/examples/ds2_ol/feat/cmvn-json2kaldi.cc
rename to speechx/speechx/frontend/audio/cmvn_json2kaldi_main.cc
diff --git a/speechx/examples/ds2_ol/feat/compute_fbank_main.cc b/speechx/speechx/frontend/audio/compute_fbank_main.cc
similarity index 100%
rename from speechx/examples/ds2_ol/feat/compute_fbank_main.cc
rename to speechx/speechx/frontend/audio/compute_fbank_main.cc
diff --git a/speechx/examples/ds2_ol/feat/linear-spectrogram-wo-db-norm-ol.cc b/speechx/speechx/frontend/audio/compute_linear_spectrogram_main.cc
similarity index 99%
rename from speechx/examples/ds2_ol/feat/linear-spectrogram-wo-db-norm-ol.cc
rename to speechx/speechx/frontend/audio/compute_linear_spectrogram_main.cc
index bbf0e690..943b74b8 100644
--- a/speechx/examples/ds2_ol/feat/linear-spectrogram-wo-db-norm-ol.cc
+++ b/speechx/speechx/frontend/audio/compute_linear_spectrogram_main.cc
@@ -12,8 +12,6 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// todo refactor, repalce with gtest
-
 #include "base/flags.h"
 #include "base/log.h"
 #include "kaldi/feat/wave-reader.h"
diff --git a/speechx/speechx/websocket/CMakeLists.txt b/speechx/speechx/websocket/CMakeLists.txt
index 582a3803..c3454c39 100644
--- a/speechx/speechx/websocket/CMakeLists.txt
+++ b/speechx/speechx/websocket/CMakeLists.txt
@@ -5,3 +5,11 @@ add_library(websocket STATIC
   websocket_client.cc
 )
 target_link_libraries(websocket PUBLIC frontend decoder nnet)
+
+add_executable(websocket_server_main ${CMAKE_CURRENT_SOURCE_DIR}/websocket_server_main.cc)
+target_include_directories(websocket_server_main PRIVATE ${SPEECHX_ROOT} ${SPEECHX_ROOT}/kaldi)
+target_link_libraries(websocket_server_main PUBLIC fst websocket ${DEPS})
+
+add_executable(websocket_client_main ${CMAKE_CURRENT_SOURCE_DIR}/websocket_client_main.cc)
+target_include_directories(websocket_client_main PRIVATE ${SPEECHX_ROOT} ${SPEECHX_ROOT}/kaldi)
+target_link_libraries(websocket_client_main PUBLIC fst websocket ${DEPS})
diff --git a/speechx/examples/ds2_ol/websocket/websocket_client_main.cc b/speechx/speechx/websocket/websocket_client_main.cc
similarity index 100%
rename from speechx/examples/ds2_ol/websocket/websocket_client_main.cc
rename to speechx/speechx/websocket/websocket_client_main.cc
diff --git a/speechx/examples/ds2_ol/websocket/websocket_server_main.cc b/speechx/speechx/websocket/websocket_server_main.cc
similarity index 100%
rename from speechx/examples/ds2_ol/websocket/websocket_server_main.cc
rename to speechx/speechx/websocket/websocket_server_main.cc
diff --git a/utils/README.md b/utils/README.md
index 163be850..db2064ef 100644
--- a/utils/README.md
+++ b/utils/README.md
@@ -1,4 +1,4 @@
 # Utils
 
 * [kaldi utils](https://github.com/kaldi-asr/kaldi/blob/cbed4ff688/egs/wsj/s5/utils)
-* [espnet utils)(https://github.com/espnet/espnet/tree/master/utils)
+* [espnet utils](https://github.com/espnet/espnet/tree/master/utils)