diff --git a/README.md b/README.md
index ac4e764..be8c1c4 100644
--- a/README.md
+++ b/README.md
@@ -36,7 +36,7 @@ The executable jar file will be created at `target/gis-<version>.jar`
 
 For more details, just run:
 ```shell script
-./gis
+./gis --help
 ```
 
 # Comparison
@@ -70,3 +70,23 @@ for i in {1..100}; do { time git submodule foreach git fetch; } 2>> git_fe_repor
 for i in {1..100}; do { time giss fe; } 2>> gis_fe_report done
 # took 5m11s832ms
 ```
+
+# Code quality
+
+Use Sonarqube to analyze code:
+```shell script
+docker run -d --name sonarqube -e SONAR_ES_BOOTSTRAP_CHECKS_DISABLE=true -p 9000:9000 sonarqube:8.9.10-community
+```
+
+Then go to `http://localhost:9000`
+- login (admin/admin), then change your password
+- go to `http://localhost:9000/projects` and click "Add a project"
+- choose "Manually"
+- input "Project key" and "Display name" e.g., "gis" then click "Set Up"
+- "Generate a token": enter a name for this token then click "Generate"
+- you will get something like this: 302481a5dee289283af983ac713174e2f2ed13da. Click "Continue"
+- as shown in the 2nd step, with maven:
+    ```shell script
+    mvn sonar:sonar -Dsonar.projectKey=gis -Dsonar.host.url=http://localhost:9000 -Dsonar.login=302481a5dee289283af983ac713174e2f2ed13da
+    ```
+- after the maven command above succcess, you will have a dashboard about `gis` project
diff --git a/src/main/java/org/nqm/command/GitCommand.java b/src/main/java/org/nqm/command/GitCommand.java
index c79599a..20a3fd3 100644
--- a/src/main/java/org/nqm/command/GitCommand.java
+++ b/src/main/java/org/nqm/command/GitCommand.java
@@ -26,6 +26,7 @@ public class GitCommand {
 
   private static final String ALL_MODULES = "***";
   private static final String ALL_SUBMODULES = "/**";
+  private static final String ORIGIN = "origin";
 
   public static final String GIT_STATUS = "status";
 
@@ -50,7 +51,7 @@ void fetch() {
 
   @Command(name = "fetch-origin", aliases = "fo")
   void fetchOrigin(@Parameters(index = "0", paramLabel = "<branch name>") String branch) {
-    forEachModuleDo(path -> deployVertx(path, "fetch", "origin", "%s:%s".formatted(branch, branch)));
+    forEachModuleDo(path -> deployVertx(path, "fetch", ORIGIN, "%s:%s".formatted(branch, branch)));
   }
 
   @Command(name = "checkout", aliases = "co")
@@ -114,7 +115,7 @@ void push(@Parameters(index = "0", paramLabel = "<branch name>") String branch,
     if (!isConfirmed("Sure you want to push to remote '%s' [Y/n]".formatted(branch))) {
       return;
     }
-    var args = isNewRemoteBranch ? new String[] { "push", "-u", "origin", branch } : shouldForcePush(isForce);
+    var args = isNewRemoteBranch ? new String[] { "push", "-u", ORIGIN, branch } : shouldForcePush(isForce);
     forEachModuleWith(
       path -> isSameBranchUnderPath(branch, path),
       path -> deployVertx(path, args));
@@ -122,7 +123,7 @@ void push(@Parameters(index = "0", paramLabel = "<branch name>") String branch,
 
   @Command(name = "remote-prune-origin", aliases = "rpo")
   void remotePruneOrigin() {
-    forEachModuleDo(path -> deployVertx(path, "remote", "prune", "origin"));
+    forEachModuleDo(path -> deployVertx(path, "remote", "prune", ORIGIN));
   }
 
   @Command(name = "stash")
diff --git a/src/main/java/org/nqm/utils/StdOutUtils.java b/src/main/java/org/nqm/utils/StdOutUtils.java
index 0606b90..ec620cd 100644
--- a/src/main/java/org/nqm/utils/StdOutUtils.java
+++ b/src/main/java/org/nqm/utils/StdOutUtils.java
@@ -130,7 +130,7 @@ private static String[] preProcessUntrackFile(String[] fileStats) {
     var newStats = new String[length + 1];
     newStats[0] = fileStats[0];
     newStats[1] = " " + UNTRACKED_SYM;
-    for (int i = 1; i < length; i++) {
+    for (var i = 1; i < length; i++) {
       newStats[i + 1] = fileStats[i];
     }
     return newStats;
diff --git a/src/main/java/org/nqm/vertx/CommandVerticle.java b/src/main/java/org/nqm/vertx/CommandVerticle.java
index 1262c50..2926017 100644
--- a/src/main/java/org/nqm/vertx/CommandVerticle.java
+++ b/src/main/java/org/nqm/vertx/CommandVerticle.java
@@ -43,7 +43,7 @@ private String[] buildCommandWithArgs(String... args) {
     var cmdWithArgs = new String[args.length + 1];
     cmdWithArgs[0] = GisConfig.GIT_HOME_DIR;
     var n = args.length;
-    for (int i = 0; i < n - 1; i++) {
+    for (var i = 0; i < n - 1; i++) {
       cmdWithArgs[i + 1] = args[i];
     }
     // for better performance it is to required all '--gis' options to be at the end of cmd
@@ -85,11 +85,15 @@ private void safelyPrint(Process pr) {
     var input = new BufferedReader(new InputStreamReader(pr.getInputStream()));
     var sb = new StringBuilder(infof("%s", "" + path.getFileName()));
     var isOneLineOpt = "--gis-one-line".equals(gisOption);
+    var isStatusCmd = commandWithArgs[1].equals(GitCommand.GIT_STATUS);
     try {
       while (isNotBlank(line = input.readLine())) {
-        sb.append(commandWithArgs[1].equals(GitCommand.GIT_STATUS)
-          ? isOneLineOpt ? gitStatusOneLine(line) : gitStatus(line)
-          : "%n  %s".formatted(line));
+        if (isStatusCmd) {
+          sb.append(isOneLineOpt ? gitStatusOneLine(line) : gitStatus(line));
+        }
+        else {
+          sb.append("%n  %s".formatted(line));
+        }
       }
       out.println(sb.toString());
       Optional.of(pr.waitFor())