diff --git a/README.md b/README.md
index fd1285c..300816f 100644
--- a/README.md
+++ b/README.md
@@ -3,39 +3,32 @@
 [![Build Status](https://travis-ci.org/announce/crx-mortal.svg?branch=master)](https://travis-ci.org/announce/crx-mortal)
 
 
-## Getting Started
+## Getting started
 
-1. Install the Chrome Extension at [**Chrome Web Store**](https://chrome.google.com/webstore/detail/crx-mortal/plbhlfecmbmkphfgcpoijlidjapddidj?utm_source=github)
+1. Install the extension at [**Chrome Web Store**](https://chrome.google.com/webstore/detail/crx-mortal/fgnhcpkfpdiaeikgdjbgfodclmnpbjno?utm_source=github)
+2. Submit your game log at https://mjai.ekyu.moe/
+
+## How crx-mortal works
+
+This extension annotates your less optimal moves based on the Mortal's score where `πτ​(a∣s)×100 < 5.0`.
 
 ## Development
 
 Prerequisites:
 
-* Docker
 * Node v18
+* `jq` command
 
-Run:
+To run in the development mode:
 
 ```bash
-./app start
+npm run watch
 ```
 
-For the release:
+To release the extension:
 
 ```bash
-./app release
+npm run build
 ```
 
-## Project Links
-
-* Upstream work: [trunk](https://github.com/announce/crx-mortal/compare/master...ymkjp:master)
-* Demo app: [crx](https://chrome.google.com/webstore/detail/crx-mortal/plbhlfecmbmkphfgcpoijlidjapddidj?utm_source=github)
-* Release: [Chrome Developer Dashboard](https://chrome.google.com/webstore/developer/dashboard)
-
-## Documents
-
-* CRX
-  * [Declare Permissions](https://developer.chrome.com/extensions/declare_permissions)
-  * [chrome\.i18n](https://developer.chrome.com/extensions/i18n)
-* ImageMagick
-  * [Text Handling \- IM v6](http://www.imagemagick.org/Usage/text/#label_bestfit)
+Then submit the bundled package at [**Chrome Developer Dashboard**](https://chrome.google.com/webstore/developer/dashboard).
diff --git a/package.json b/package.json
index c0d1df8..05648dd 100644
--- a/package.json
+++ b/package.json
@@ -1,18 +1,18 @@
 {
   "name": "crx-mortal",
-  "version": "1.0.0",
-  "description": "crx-mortal",
-  "main": "index.js",
+  "version": "1.0.1",
+  "description": "A Chrome extension to help Mahjong players spot their less optimal moves",
   "scripts": {
     "watch": "webpack --config webpack/webpack.dev.js --watch",
     "build": "npm-run-all style clean build:** bundle",
+    "build:manifest": "./app update-manifest-version",
     "build:js": "webpack --config webpack/webpack.prod.js",
-    "bundle": "zip -r dist-$(date +%s).zip ./dist/*",
+    "bundle": "./app bundle-dist",
     "clean": "rimraf dist",
     "test": "npx jest",
     "style": "prettier --write \"src/**/*.{ts,tsx}\" \"public/**/*.{json,html,css}\""
   },
-  "author": "",
+  "author": "Kenta Yamamoto <ymkjp@jaist.ac.jp>",
   "license": "MIT",
   "repository": {
     "type": "git",
diff --git a/public/manifest.json b/public/manifest.json
index b9ce70a..962a619 100644
--- a/public/manifest.json
+++ b/public/manifest.json
@@ -1,18 +1,20 @@
 {
   "manifest_version": 3,
-
   "name": "crx-mortal",
-  "description": "annotating bad-moves",
-  "version": "1.0",
-
+  "description": "This extension helps Mahjong players spot their less optimal moves",
+  "version": "1.0.1",
   "action": {
     "default_icon": "icon.png"
   },
-
   "content_scripts": [
     {
-      "matches": ["https://mjai.ekyu.moe/*"],
-      "js": ["js/vendor.js", "js/content_script.js"]
+      "matches": [
+        "https://mjai.ekyu.moe/*"
+      ],
+      "js": [
+        "js/vendor.js",
+        "js/content_script.js"
+      ]
     }
   ]
 }
diff --git a/script/app.bash b/script/app.bash
index 067a3b3..9ac1d6d 100755
--- a/script/app.bash
+++ b/script/app.bash
@@ -3,20 +3,16 @@
 app () {
   set -u
 
-  start () {
-    export NODE_ENV=development
-    npm start
+  bundle-dist () {
+    [[ $(command -v zip) ]] || return
+    zip -r ./var/dist-$(date +%s).zip ./dist/*
   }
 
-  release () {
-    export NODE_ENV=production
-    npm run build
-  }
-
-  die () {
-    MESSAGE="${1:-Something went wrong.}"
-    echo "[$(basename "$0")] ERROR: ${MESSAGE}" >&2
-    exit 1
+  update-manifest-version () {
+    [[ $(command -v jq) ]] || return
+    PACKAGE_VERSION="$(jq '.version' package.json)"
+    MANIFEST="$(jq ".version = ${PACKAGE_VERSION}" public/manifest.json)"
+    echo -e "${MANIFEST}" > public/manifest.json
   }
 
   usage () {
diff --git a/src/content_script.tsx b/src/content_script.tsx
index b202906..adbc944 100644
--- a/src/content_script.tsx
+++ b/src/content_script.tsx
@@ -1,48 +1,56 @@
 /**
  * https://mjai.ekyu.moe/report/888288d74f7ed24c.html#kyoku-6-0
  */
+class CrxMortal {
+  static DEFAULT_THRESHOLD = 5.0;
+  createSpan = (text: string) => {
+    const span = document.createElement("span");
+    span.innerText = text;
+    span.style.background = `#ffd5d5`;
+    span.style.margin = `auto .5rem`;
+    span.style.fontWeight = `bold`;
+    return span;
+  };
 
-const THRESHOLD = 5.0;
-const createSpan = (text: string) => {
-  const suggestion = document.createElement("span");
-  suggestion.innerText = text;
-  suggestion.style.background = `#ffd5d5`;
-  suggestion.style.margin = `auto .5rem`;
-  suggestion.style.fontWeight = `bold`;
-  return suggestion;
-};
+  main = () => {
+    const scores = [...document.querySelectorAll(`body section details.entry`)]
+      .map((element) => {
+        const tile = element.querySelector(`span svg.tile use`) as SVGAElement;
+        if (tile === null) {
+          return null;
+        }
+        // '#pai-9s'
+        const score = element
+          .querySelector(`table [href*="${tile.href.baseVal}"]`)
+          ?.closest(`tr`)
+          ?.querySelector(`td:nth-child(3)`) as HTMLElement;
+        const scoreNum = parseFloat(score.textContent || ``);
+        if (scoreNum < CrxMortal.DEFAULT_THRESHOLD) {
+          const suggestion = this.createSpan(score.textContent || ``);
+          element.querySelector(`:scope > span`)?.appendChild(suggestion);
+        } else {
+          element.removeAttribute(`open`);
+        }
+        return scoreNum;
+      })
+      .filter((score) => score !== null);
 
-const scores = [...document.querySelectorAll(`body section details.entry`)]
-  .map((element) => {
-    const tile = element.querySelector(`span svg.tile use`) as SVGAElement;
-    if (tile === null) {
-      return null;
-    }
-    // '#pai-9s'
-    const score = element
-      .querySelector(`table [href*="${tile.href.baseVal}"]`)
-      ?.closest(`tr`)
-      ?.querySelector(`td:nth-child(3)`) as HTMLElement;
-    const scoreNum = parseFloat(score.textContent || ``);
-    if (scoreNum < THRESHOLD) {
-      const suggestion = createSpan(score.textContent || ``);
-      element.querySelector(`:scope > span`)?.appendChild(suggestion);
-    } else {
-      element.removeAttribute(`open`);
-    }
-    return scoreNum;
-  })
-  .filter((score) => score !== null);
-
-const badMoves = scores.filter(
-  (score) => score !== null && score < THRESHOLD
-).length;
-const totalMoves = scores.length;
-
-const metrics = createSpan(
-  `${badMoves}/${totalMoves} = ${Math.round((badMoves / totalMoves) * 100)}%`
-);
-document
-  .querySelector("body > details.collapse:nth-child(6) > summary")
-  ?.appendChild(metrics);
+    const totalMoves = scores.length;
+    const badMoves = scores.filter(
+      (score) => score !== null && score < CrxMortal.DEFAULT_THRESHOLD
+    ).length;
+    const metrics = this.createSpan(
+      `${badMoves}/${totalMoves} = ${
+        totalMoves > 0 ? Math.round((badMoves / totalMoves) * 100) : NaN
+      }%`
+    );
+    document
+      .querySelector("body > details.collapse:nth-child(6) > summary")
+      ?.appendChild(metrics);
+  };
+}
 
+if (require.main === module) {
+  const crx = new CrxMortal();
+  crx.main();
+}
diff --git a/src/popup.tsx b/src/popup.tsx
index d4244f1..3444136 100644
--- a/src/popup.tsx
+++ b/src/popup.tsx
@@ -8,7 +8,7 @@ const Popup = () => {
   useEffect(() => {
     (async () => {
       await chrome.action.setBadgeText({ text: count.toString() });
-    })()
+    })();
   }, [count]);
 
   useEffect(() => {