diff --git a/local-cli/cli.json b/local-cli/cli.json
index 32a04d6..1c9c03a 100644
--- a/local-cli/cli.json
+++ b/local-cli/cli.json
@@ -25,33 +25,45 @@
       "description": "Bundle javascript and copy assets."
     },
     "bundle": {
-      "description": "Bundle javascript code only."
+      "description": "Bundle javascript code only.",
+      "options": {
+        "dev": {
+          "default": false
+        },
+        "platform": {
+          "hasValue": true
+        },
+        "entryFile": {
+          "default": "index.${platform}.js",
+          "hasValue": true
+        },
+        "intermediaDir": {
+          "default": "build/intermedia/${platform}",
+          "hasValue": true
+        },
+        "output": {
+          "default": "build/output/${platform}.${hash}.ppk",
+          "hasValue": true
+        },
+        "verbose": {
+
+        }
+      }
     },
     "release": {
       "description": "Push builded file to server."
+    },
+    "diff": {
+      "description": "Create diff patch",
+      "options": {
+        "output": {
+          "default": "build/output/diff",
+          "hasValue": true
+        }
+      }
     }
   },
   "globalOptions":{
-    "dev": {
-      "default": false
-    },
-    "platform": {
-      "hasValue": true
-    },
-    "entryFile": {
-      "default": "index.${platform}.js",
-      "hasValue": true
-    },
-    "intermediaDir": {
-      "default": "build/intermedia/${platform}",
-      "hasValue": true
-    },
-    "output": {
-      "default": "build/output/${platform}.${hash}.ppk",
-      "hasValue": true
-    },
-    "verbose": {
 
-    }
   }
 }
diff --git a/local-cli/src/bundle.js b/local-cli/src/bundle.js
index 22bf3b0..adda502 100644
--- a/local-cli/src/bundle.js
+++ b/local-cli/src/bundle.js
@@ -10,6 +10,7 @@ import {
 } from './utils';
 import * as fs from 'fs';
 import {ZipFile} from 'yazl';
+import {open as openZipFile} from 'yauzl';
 
 import crypto from 'crypto';
 
@@ -54,8 +55,9 @@ async function calcMd5ForDirectory(dir) {
 }
 
 async function pack(dir, output){
-  await mkdir(path.dirname(output))
   const hash = await calcMd5ForDirectory(dir);
+  const realOutput = output.replace(/\$\{hash\}/g, hash);
+  await mkdir(path.dirname(realOutput))
   await new Promise((resolve, reject) => {
     var zipfile = new ZipFile();
 
@@ -83,7 +85,7 @@ async function pack(dir, output){
     addDirectory(dir, '');
 
     zipfile.outputStream.on('error', err => reject(err));
-    zipfile.outputStream.pipe(fs.createWriteStream(output.replace(/\$\{hash\}/g, hash)))
+    zipfile.outputStream.pipe(fs.createWriteStream(realOutput))
       .on("close", function() {
         resolve();
       });
@@ -92,6 +94,27 @@ async function pack(dir, output){
   console.log('Bundled with hash: ' + hash);
 }
 
+function enumZipEntries(zipFn, callback) {
+  return new Promise((resolve, reject) => {
+    openZipFile(zipFn, {lazyEntries:true}, (err, zipfile) => {
+      if (err) {
+        return reject(err);
+      }
+      zipfile.on('end', resolve);
+      zipfile.on('error', reject);
+      zipfile.on('entry', entry => {
+        const result = callback(entry, zipfile);
+        if (result && typeof(result.then) === 'function') {
+          result.then(() => zipfile.readEntry());
+        } else {
+          zipfile.readEntry();
+        }
+      });
+      zipfile.readEntry();
+    });
+  });
+}
+
 export const commands = {
   bundle: async function({options}){
     const {
@@ -142,5 +165,79 @@ export const commands = {
     console.log('Packing');
 
     await pack(intermediaDir, output);
+  },
+
+  async diff({args, options}) {
+    const [origin, next] = args;
+    const {output} = options;
+
+    if (!origin || !next) {
+      console.error('pushy diff <origin> <next>');
+      process.exit(1);
+    }
+
+    //Read crc32 map from origin
+    const originMap = {};
+    const originEntries = {};
+
+    await enumZipEntries(origin, entry => {
+      if (!/\/$/.test(entry.fileName)) {
+        // isFile
+        originEntries[entry.fileName] = entry.crc32;
+        originMap[entry.crc32] = entry.fileName;
+      }
+    });
+
+    const copies = {};
+
+    var zipfile = new ZipFile();
+
+    const writePromise = new Promise((resolve, reject)=>{
+      zipfile.outputStream.on('error', err => {throw err;});
+      zipfile.outputStream.pipe(fs.createWriteStream(output))
+        .on("close", function() {
+          resolve();
+        });
+    });
+
+    await enumZipEntries(next, (entry, nextZipfile) => {
+      if (/\/$/.test(entry.fileName)) {
+        // Directory
+        zipfile.addEmptyDirectory(entry.fileName);
+      } else {
+        // If same file.
+        if (originEntries[entry.fileName] === entry.crc32) {
+          console.log('keep:', entry.fileName);
+          copies[entry.fileName] = 1;
+          return;
+        }
+        // If moved from other place
+        if (originMap[entry.crc32]){
+          console.log('move:' + originMap[entry.crc32] + '->' + entry.fileName);
+          copies[entry.fileName] = originMap[entry.crc32];
+          return;
+        }
+
+        // TODO: test diff
+        console.log('add:' + entry.fileName);
+
+        return new Promise((resolve, reject)=>{
+          nextZipfile.openReadStream(entry, function(err, readStream) {
+            if (err){
+              return reject(err);
+            }
+            zipfile.addReadStream(readStream, entry.fileName);
+            readStream.on('end', () => {
+              console.log('add finished');
+              resolve();
+            });
+          });
+        })
+      }
+    });
+
+    zipfile.addBuffer(new Buffer(JSON.stringify({copies})), '__diff.json');
+    zipfile.end();
+    await writePromise;
   }
 };
diff --git a/package.json b/package.json
index c215d86..1633d1e 100644
--- a/package.json
+++ b/package.json
@@ -4,7 +4,8 @@
   "description": "react-native hot update",
   "main": "index.js",
   "scripts": {
-    "test": "echo \"Error: no test specified\" && exit 1"
+    "test": "echo \"Error: no test specified\" && exit 1",
+    "prepublish": "node_modules/.bin/babel local-cli/src --out-dir local-cli/lib"
   },
   "repository": {
     "type": "git",
@@ -31,6 +32,7 @@
     "isomorphic-fetch": "^2.2.1",
     "mkdir-recursive": "^0.2.1",
     "read": "^1.0.7",
+    "yauzl": "^2.4.1",
     "yazl": "^2.3.0"
   },
   "devDependencies": {