diff --git a/git_commit.sh b/git_commit.sh
new file mode 100755
index 0000000..17378e7
--- /dev/null
+++ b/git_commit.sh
@@ -0,0 +1,40 @@
+#/usr/bin/env bash
+#
+# Environment Variables:
+#   NEMU_HOME
+set -x
+
+STUID=ysyx_22040000
+STUNAME=李心杨
+
+TRACER=tracer-ysyx
+GITFLAGS="-q --author=$TRACER<tracer@ysyx.org> --no-verify --allow-empty"
+
+YSYX_HOME=$NEMU_HOME/..
+WORK_BRANCH=$(git rev-parse --abbrev-ref HEAD)
+WORK_INDEX=$YSYX_HOME/.git/index.${WORK_BRANCH}
+TRACER_BRANCH=$TRACER
+
+LOCK_DIR=$YSYX_HOME/.git/
+
+git_soft_checkout () {
+    git checkout --detach -q && git reset --soft $1 -q -- && git checkout $1 -q -- ;
+}
+
+git_commit () {
+    # create tracer branch if not existent
+    git branch $TRACER_BRANCH -q 2>/dev/null || true
+    # backup git index
+    cp -a .git/index $WORK_INDEX
+    # switch to tracer branch
+    git_soft_checkout "$TRACER_BRANCH"
+    # add files to commit
+    git add . -A --ignore-errors
+    # generate commit msg, commit changes in tracer branch
+    printf "> $1 \n $STUID $STUNAME \n $(uname -a) \n $(uptime)\n" | git commit -F - $GITFLAGS
+    git_soft_checkout "$WORK_BRANCH"
+    mv $WORK_INDEX .git/index
+}
+
+git_commit $1
+
diff --git a/npc/CMakeLists.txt b/npc/CMakeLists.txt
index 8d3e4dd..d5ca275 100644
--- a/npc/CMakeLists.txt
+++ b/npc/CMakeLists.txt
@@ -5,8 +5,8 @@ set (CMAKE_CXX_STANDARD 11)
 cmake_policy(SET CMP0144 NEW)
 
 execute_process(
-  COMMAND ${CMAKE_SOURCE_DIR}/../git_commit.sh "configure\ npc"
-  WORKING_DIRECTORY ../
+  COMMAND ${CMAKE_SOURCE_DIR}/../git_commit.sh "configure npc"
+  WORKING_DIRECTORY ${CMAKE_SOURCE_DIR}/..
 )
 
 find_package(SDL2 REQUIRED)