diff --git a/.eslintrc.js b/.eslintrc.js
index fcb5589..0b9d0f5 100644
--- a/.eslintrc.js
+++ b/.eslintrc.js
@@ -1,7 +1,7 @@
 module.exports = {
   parser: 'babel-eslint',
   extends: 'standard',
-  plugins: ['mocha'],
+  plugins: ['mocha', 'chai-friendly'],
   parserOptions: {
     'ecmaVersion':2017
   },
@@ -9,6 +9,8 @@ module.exports = {
   rules: {
     'space-before-function-paren': ['error', 'never'],
     'no-underscore-dangle': 0,
-    'mocha/no-exclusive-tests': 'error'
+    'mocha/no-exclusive-tests': 'error',
+    "no-unused-expressions": 0,
+    "chai-friendly/no-unused-expressions": 2
   }
 }
diff --git a/lib/community.js b/lib/community.js
new file mode 100644
index 0000000..bbf47d5
--- /dev/null
+++ b/lib/community.js
@@ -0,0 +1,24 @@
+import Transaction from './transaction'
+
+/**
+ * Community managing class
+ */
+class Community {
+  constractor(wallet) {
+    this.wallet = wallet
+  }
+  /**
+   * create new Community.
+   * @param name (unique) as communityId.
+   * @return {Promise<Transaction>}
+   */
+  async create(name) {
+    return new Transaction()
+  }
+
+  get [Symbol.toStringTag]() {
+    return 'Community'
+  }
+}
+
+export default Community
diff --git a/lib/masa.js b/lib/masa.js
index 8a907c4..1b0b722 100644
--- a/lib/masa.js
+++ b/lib/masa.js
@@ -1,5 +1,28 @@
-function masa(provider) {
-  console.log('masa.js')
+import MasaPoint from './masa_point'
+import MasaCoin from './masa_coin'
+
+/**
+ * Masa system client library class.
+ */
+class Masa {
+  /**
+   * @constructor
+   */
+  constructor() {
+    console.log('masa.js')
+    const provider = {}
+    this.point = new class extends MasaPoint {
+      feedback(to, communityId, feelingsId, msg) {
+        throw new TypeError('Not support function. Please use MasaTx.')
+      }
+    }(provider, null)
+    this.coin = new class extends MasaCoin {
+      transfer(address) {
+        throw new TypeError('Not support function. Please use MasaTx.')
+      }
+    }(provider, null)
+  }
 }
 
+const masa = new Masa()
 export default masa
diff --git a/lib/masa_coin.js b/lib/masa_coin.js
new file mode 100644
index 0000000..e957ec3
--- /dev/null
+++ b/lib/masa_coin.js
@@ -0,0 +1,33 @@
+import Transaction from './transaction'
+
+/**
+ * MasaCoin managing class
+ */
+class MasaCoin {
+  constructor(provider, wallet) {
+    this.provider = provider
+    this.wallet = wallet
+  }
+  /**
+   * Get the balance of coin.
+   * @param address to query the balance of.
+   * @returns {Promise<number>} amount of coin.
+   */
+  async balanceOf(address) {
+    // TODO: implement
+    return 100
+  }
+
+  /**
+   * Send coin to other user.
+   * @param address receiver address
+   * @param amount sending amount
+   * @return {Promise<Transaction>}
+   */
+  async transfer(address, amount) {
+    // TODO: implement
+    return new Transaction()
+  }
+}
+
+export default MasaCoin
diff --git a/lib/masa_point.js b/lib/masa_point.js
new file mode 100644
index 0000000..a854018
--- /dev/null
+++ b/lib/masa_point.js
@@ -0,0 +1,62 @@
+import Transaction from './transaction'
+
+/**
+ * MasaPoint managing class.
+ * This class provide functions for access to MasaPoint Smart Contract on Ethereum.
+ */
+class MasaPoint {
+  /**
+   * @constructor
+   * @param provider require for explorer functions
+   * @param wallet require for signed functions
+   */
+  constructor(provider, wallet) {
+    this.provider = provider
+    this.wallet = wallet
+  }
+  /**
+   * Get the amount of valid points.
+   * @param address the owner of masa point
+   * @returns {Promise<number>} point of the user
+   */
+  async amountOf(address) {
+    // TODO: implement
+    if (address === '0x6861766520636f696e20697300000000000000b8') {
+      return 200
+    }
+    return 500
+  }
+
+  /**
+   * Get the amount of valid points in a specific community.
+   * @param address the owner of masa point
+   * @param communityId community id
+   * @returns {Promise<number>} point of the user in the community
+   */
+  async communityAmountOf(address, communityId) {
+    // TODO: implement
+    return 200
+  }
+
+  /**
+   * Create feedback raw transaction.
+   * @param to feedback received user address
+   * @param communityId the community regarding of feedback
+   * @param feelingsId Gratitude: 1 / Empathy: 2 /Support: 3
+   * @param msg reason for feelings
+   * @returns {Promise<Transaction>}
+   */
+  async feedback(to, communityId, feelingsId, msg) {
+    // TODO: implement
+    if (this.wallet === undefined) {
+      throw new TypeError('Wallet is NULL! need for sign.')
+    }
+    return new Transaction()
+  }
+
+  get [Symbol.toStringTag]() {
+    return 'MasaPoint'
+  }
+}
+
+export default MasaPoint
diff --git a/lib/masa_tx.js b/lib/masa_tx.js
new file mode 100644
index 0000000..e40f15b
--- /dev/null
+++ b/lib/masa_tx.js
@@ -0,0 +1,40 @@
+import Wallet from './wallet'
+import MasaPoint from './masa_point'
+import MasaCoin from './masa_coin'
+import Community from './community'
+
+/**
+ * MasaTx class provide functions that create signed transaction.
+ * This class needs wallet for pick up private key.
+ *
+ * Usage:
+ *   const masaTx = new MasaTx() // generate new wallet.
+ * or
+ *   const masaTx = new MasaTx(mnemonic) // restore wallet from specify mnemonic
+ *
+ *   masaTx.point.feedback(~~~~) // return signed transaction for Masa Point Feedback.
+ *   masaTx.coin.transfer(~~~) // return signed transaction for Masa Coin Transfer.
+ *   masaTx.community.create(~~~) // return signed transaction for Community creation.
+ */
+class MasaTx {
+  constructor(mnemonic = '') {
+    mnemonic = mnemonic === undefined || mnemonic === '' ? Wallet.generateMnemonic() : mnemonic
+    this.wallet = new Wallet(mnemonic)
+    this.point = new class extends MasaPoint {
+      amountOf(address) {
+        throw new TypeError('Not support function. Please use Masa.')
+      }
+      communityAmountOf(address, communityId) {
+        throw new TypeError('Not support function. Please use Masa.')
+      }
+    }(null, this.wallet)
+    this.coin = new class extends MasaCoin {
+      async balanceOf() {
+        throw new TypeError('Not support function. Please use Masa.')
+      }
+    }(null, this.wallet)
+    this.community = new Community(this.wallet)
+  }
+}
+
+export default MasaTx
diff --git a/lib/transaction.js b/lib/transaction.js
new file mode 100644
index 0000000..044d43f
--- /dev/null
+++ b/lib/transaction.js
@@ -0,0 +1,37 @@
+/**
+ * Class for Provide convenience access to Ethereum Transaction.
+ */
+class Transaction {
+  /**
+   * sign this transaction
+   * @param privateKey
+   */
+  signature(privateKey) {
+    // TODO: implement
+  }
+
+  /**
+   * serialize to json format
+   * @return {JSON} json formatted transaction
+   */
+  toJSON() {
+    // TODO: implement
+    return {
+      to: '',
+      nonce: 2,
+      gas: 0x01,
+      gasPrice: 20 * 10 ** 9,
+      data: '0x0000000001',
+      chainId: 4447,
+      v: '',
+      s: '',
+      r: ''
+    }
+  }
+
+  get [Symbol.toStringTag]() {
+    return 'Transaction'
+  }
+}
+
+export default Transaction
diff --git a/lib/wallet.js b/lib/wallet.js
new file mode 100644
index 0000000..04f4ccc
--- /dev/null
+++ b/lib/wallet.js
@@ -0,0 +1,48 @@
+import bip39 from 'bip39'
+import hdkey from 'ethereumjs-wallet/hdkey'
+
+/**
+ * Masa Wallet class.
+ * Provide simple wallet functions.
+ * Usage:
+ *   const mnemonic = Wallet.generateMnemonic()
+ *   const wallet = new Wallet(mnemonic)
+ *   const privateKey = wallet.privateKey // return Buffer
+ *   const address = wallet.address // return string
+ */
+class Wallet {
+  get HD_PATH() {
+    return "m/44'/60'/0'/0/0"
+  }
+
+  /**
+   * generate mnemonic of master seed.
+   * @return {string} mnemonic
+   */
+  static generateMnemonic() {
+    return bip39.generateMnemonic()
+  }
+
+  /**
+   * create HDWallet from master seed mnemonic.
+   * @constructor
+   * @param mnemonic {string}
+   */
+  constructor(mnemonic) {
+    if (!bip39.validateMnemonic(mnemonic)) {
+      throw new TypeError('invalid mnemonic!')
+    }
+    this.mnemonic = mnemonic
+    this._hdwallet = hdkey.fromMasterSeed(bip39.mnemonicToSeed(mnemonic))
+    this._wallet = this._hdwallet.derivePath(this.HD_PATH).getWallet()
+    this.address = '0x' + this._wallet.getAddress().toString('hex')
+    this.privateKey = this._wallet.getPrivateKey()
+    this.publicKey = this._wallet.getPublicKey()
+  }
+
+  get [Symbol.toStringTag]() {
+    return 'Wallet'
+  }
+}
+
+export default Wallet
diff --git a/package-lock.json b/package-lock.json
index 8bd7676..3e6aa6a 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -631,6 +631,17 @@
         "regenerator-transform": "^0.13.3"
       }
     },
+    "@babel/plugin-transform-runtime": {
+      "version": "7.0.0",
+      "resolved": "https://registry.npmjs.org/@babel/plugin-transform-runtime/-/plugin-transform-runtime-7.0.0.tgz",
+      "integrity": "sha512-yECRVxRu25Nsf6IY5v5XrXhcW9ZHomUQiq30VO8H7r3JYPcBJDTcxZmT+6v1O3QKKrDp1Wp40LinGbcd+jlp9A==",
+      "dev": true,
+      "requires": {
+        "@babel/helper-module-imports": "^7.0.0",
+        "@babel/helper-plugin-utils": "^7.0.0",
+        "resolve": "^1.8.1"
+      }
+    },
     "@babel/plugin-transform-shorthand-properties": {
       "version": "7.0.0",
       "resolved": "https://registry.npmjs.org/@babel/plugin-transform-shorthand-properties/-/plugin-transform-shorthand-properties-7.0.0.tgz",
@@ -689,6 +700,16 @@
         "regexpu-core": "^4.1.3"
       }
     },
+    "@babel/polyfill": {
+      "version": "7.0.0",
+      "resolved": "https://registry.npmjs.org/@babel/polyfill/-/polyfill-7.0.0.tgz",
+      "integrity": "sha512-dnrMRkyyr74CRelJwvgnnSUDh2ge2NCTyHVwpOdvRMHtJUyxLtMAfhBN3s64pY41zdw0kgiLPh6S20eb1NcX6Q==",
+      "dev": true,
+      "requires": {
+        "core-js": "^2.5.7",
+        "regenerator-runtime": "^0.11.1"
+      }
+    },
     "@babel/preset-env": {
       "version": "7.0.0",
       "resolved": "https://registry.npmjs.org/@babel/preset-env/-/preset-env-7.0.0.tgz",
@@ -738,6 +759,23 @@
         "semver": "^5.3.0"
       }
     },
+    "@babel/runtime": {
+      "version": "7.0.0",
+      "resolved": "https://registry.npmjs.org/@babel/runtime/-/runtime-7.0.0.tgz",
+      "integrity": "sha512-7hGhzlcmg01CvH1EHdSPVXYX1aJ8KCEyz6I9xYIi/asDtzBPMyMhVibhM/K6g/5qnKBwjZtp10bNZIEFTRW1MA==",
+      "dev": true,
+      "requires": {
+        "regenerator-runtime": "^0.12.0"
+      },
+      "dependencies": {
+        "regenerator-runtime": {
+          "version": "0.12.1",
+          "resolved": "https://registry.npmjs.org/regenerator-runtime/-/regenerator-runtime-0.12.1.tgz",
+          "integrity": "sha512-odxIc1/vDlo4iZcfXqRYFj0vpXFNoGdKMAUieAlFYO6m/nl5e9KR/beGf41z4a1FI+aQgtjhuaSlDxQ0hmkrHg==",
+          "dev": true
+        }
+      }
+    },
     "@babel/template": {
       "version": "7.0.0",
       "resolved": "https://registry.npmjs.org/@babel/template/-/template-7.0.0.tgz",
@@ -1085,6 +1123,11 @@
         "acorn": "^5.0.3"
       }
     },
+    "aes-js": {
+      "version": "3.1.1",
+      "resolved": "https://registry.npmjs.org/aes-js/-/aes-js-3.1.1.tgz",
+      "integrity": "sha512-cEA0gBelItZZV7iBiL8ApCiNgc+gBWJJ4uoORhbu6vOqAJ0UL9wIlxr4RI7ij9SSVzy6AnPwiu37kVYiHCl3nw=="
+    },
     "ajv": {
       "version": "6.5.3",
       "resolved": "https://registry.npmjs.org/ajv/-/ajv-6.5.3.tgz",
@@ -1364,6 +1407,14 @@
         }
       }
     },
+    "base-x": {
+      "version": "3.0.4",
+      "resolved": "https://registry.npmjs.org/base-x/-/base-x-3.0.4.tgz",
+      "integrity": "sha512-UYOadoSIkEI/VrRGSG6qp93rp2WdokiAiNYDfGW5qURAY8GiAQkvMbwNNSDYiVJopqv4gCna7xqf4rrNGp+5AA==",
+      "requires": {
+        "safe-buffer": "^5.0.1"
+      }
+    },
     "base64-js": {
       "version": "1.3.0",
       "resolved": "https://registry.npmjs.org/base64-js/-/base64-js-1.3.0.tgz",
@@ -1382,6 +1433,31 @@
       "integrity": "sha1-RqoXUftqL5PuXmibsQh9SxTGwgU=",
       "dev": true
     },
+    "bindings": {
+      "version": "1.3.0",
+      "resolved": "https://registry.npmjs.org/bindings/-/bindings-1.3.0.tgz",
+      "integrity": "sha512-DpLh5EzMR2kzvX1KIlVC0VkC3iZtHKTgdtZ0a3pglBZdaQFjt5S9g9xd1lE+YvXyfd6mtCeRnrUfOLYiTMlNSw=="
+    },
+    "bip39": {
+      "version": "2.5.0",
+      "resolved": "https://registry.npmjs.org/bip39/-/bip39-2.5.0.tgz",
+      "integrity": "sha512-xwIx/8JKoT2+IPJpFEfXoWdYwP7UVAoUxxLNfGCfVowaJE7yg1Y5B1BVPqlUNsBq5/nGwmFkwRJ8xDW4sX8OdA==",
+      "requires": {
+        "create-hash": "^1.1.0",
+        "pbkdf2": "^3.0.9",
+        "randombytes": "^2.0.1",
+        "safe-buffer": "^5.0.1",
+        "unorm": "^1.3.3"
+      }
+    },
+    "bip66": {
+      "version": "1.1.5",
+      "resolved": "https://registry.npmjs.org/bip66/-/bip66-1.1.5.tgz",
+      "integrity": "sha1-AfqHSHhcpwlV1QESF9GzE5lpyiI=",
+      "requires": {
+        "safe-buffer": "^5.0.1"
+      }
+    },
     "bluebird": {
       "version": "3.5.1",
       "resolved": "https://registry.npmjs.org/bluebird/-/bluebird-3.5.1.tgz",
@@ -1391,8 +1467,7 @@
     "bn.js": {
       "version": "4.11.8",
       "resolved": "https://registry.npmjs.org/bn.js/-/bn.js-4.11.8.tgz",
-      "integrity": "sha512-ItfYfPLkWHUjckQCk8xC+LwxgK8NYcXywGigJgSwOP8Y2iyWT4f2vsZnoOXTTbo+o5yXmIUJ4gn5538SO5S3gA==",
-      "dev": true
+      "integrity": "sha512-ItfYfPLkWHUjckQCk8xC+LwxgK8NYcXywGigJgSwOP8Y2iyWT4f2vsZnoOXTTbo+o5yXmIUJ4gn5538SO5S3gA=="
     },
     "brace-expansion": {
       "version": "1.1.11",
@@ -1436,8 +1511,7 @@
     "brorand": {
       "version": "1.1.0",
       "resolved": "https://registry.npmjs.org/brorand/-/brorand-1.1.0.tgz",
-      "integrity": "sha1-EsJe/kCkXjwyPrhnWgoM5XsiNx8=",
-      "dev": true
+      "integrity": "sha1-EsJe/kCkXjwyPrhnWgoM5XsiNx8="
     },
     "browser-stdout": {
       "version": "1.3.1",
@@ -1449,7 +1523,6 @@
       "version": "1.2.0",
       "resolved": "https://registry.npmjs.org/browserify-aes/-/browserify-aes-1.2.0.tgz",
       "integrity": "sha512-+7CHXqGuspUn/Sl5aO7Ea0xWGAtETPXNSAjHo48JfLdPWcMng33Xe4znFvQweqc/uzk5zSOI3H52CYnjCfb5hA==",
-      "dev": true,
       "requires": {
         "buffer-xor": "^1.0.3",
         "cipher-base": "^1.0.0",
@@ -1527,6 +1600,24 @@
         "node-releases": "^1.0.0-alpha.11"
       }
     },
+    "bs58": {
+      "version": "4.0.1",
+      "resolved": "https://registry.npmjs.org/bs58/-/bs58-4.0.1.tgz",
+      "integrity": "sha1-vhYedsNU9veIrkBx9j806MTwpCo=",
+      "requires": {
+        "base-x": "^3.0.2"
+      }
+    },
+    "bs58check": {
+      "version": "2.1.2",
+      "resolved": "https://registry.npmjs.org/bs58check/-/bs58check-2.1.2.tgz",
+      "integrity": "sha512-0TS1jicxdU09dwJMNZtVAfzPi6Q6QeN0pM1Fkzrjn+XYHvzMKPU3pHVpva+769iNVSfIYWf7LJ6WR+BuuMf8cA==",
+      "requires": {
+        "bs58": "^4.0.0",
+        "create-hash": "^1.1.0",
+        "safe-buffer": "^5.1.2"
+      }
+    },
     "buffer": {
       "version": "4.9.1",
       "resolved": "https://registry.npmjs.org/buffer/-/buffer-4.9.1.tgz",
@@ -1547,8 +1638,7 @@
     "buffer-xor": {
       "version": "1.0.3",
       "resolved": "https://registry.npmjs.org/buffer-xor/-/buffer-xor-1.0.3.tgz",
-      "integrity": "sha1-JuYe0UIvtw3ULm42cp7VHYVf6Nk=",
-      "dev": true
+      "integrity": "sha1-JuYe0UIvtw3ULm42cp7VHYVf6Nk="
     },
     "builtin-modules": {
       "version": "1.1.1",
@@ -1704,7 +1794,6 @@
       "version": "1.0.4",
       "resolved": "https://registry.npmjs.org/cipher-base/-/cipher-base-1.0.4.tgz",
       "integrity": "sha512-Kkht5ye6ZGmwv40uUDZztayT2ThLQGfnj/T71N/XzeZeo3nf8foyW7zGTsPYkEya3m5f3cAypH+qe7YOrM1U2Q==",
-      "dev": true,
       "requires": {
         "inherits": "^2.0.1",
         "safe-buffer": "^5.0.1"
@@ -1788,6 +1877,22 @@
       "integrity": "sha1-DQcLTQQ6W+ozovGkDi7bPZpMz3c=",
       "dev": true
     },
+    "coinstring": {
+      "version": "2.3.0",
+      "resolved": "https://registry.npmjs.org/coinstring/-/coinstring-2.3.0.tgz",
+      "integrity": "sha1-zbYzY6lhUCQEolr7gsLibV/2J6Q=",
+      "requires": {
+        "bs58": "^2.0.1",
+        "create-hash": "^1.1.1"
+      },
+      "dependencies": {
+        "bs58": {
+          "version": "2.0.1",
+          "resolved": "https://registry.npmjs.org/bs58/-/bs58-2.0.1.tgz",
+          "integrity": "sha1-VZCNWPGYKrogCPob7Y+RmYopv40="
+        }
+      }
+    },
     "collection-visit": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/collection-visit/-/collection-visit-1.0.0.tgz",
@@ -1922,7 +2027,6 @@
       "version": "1.2.0",
       "resolved": "https://registry.npmjs.org/create-hash/-/create-hash-1.2.0.tgz",
       "integrity": "sha512-z00bCGNHDG8mHAkP7CtT1qVu+bFQUPjYq/4Iv3C3kWjTFV10zIjfSoeqXo9Asws8gwSHDGj/hl2u4OGIjapeCg==",
-      "dev": true,
       "requires": {
         "cipher-base": "^1.0.1",
         "inherits": "^2.0.1",
@@ -1935,7 +2039,6 @@
       "version": "1.1.7",
       "resolved": "https://registry.npmjs.org/create-hmac/-/create-hmac-1.1.7.tgz",
       "integrity": "sha512-MJG9liiZ+ogc4TzUwuvbER1JRdgvUFSB5+VR/g5h82fGaIRWMWddtKBHi7/sVhfjQZ6SehlyhvQYrcYkaUIpLg==",
-      "dev": true,
       "requires": {
         "cipher-base": "^1.0.3",
         "create-hash": "^1.1.0",
@@ -2167,6 +2270,16 @@
       "integrity": "sha512-jnjyiM6eRyZl2H+W8Q/zLMA481hzi0eszAaBUzIVnmYVDBbnLxVNnfu1HgEBvCbL+71FrxMl3E6lpKH7Ge3OXA==",
       "dev": true
     },
+    "drbg.js": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/drbg.js/-/drbg.js-1.0.1.tgz",
+      "integrity": "sha1-Pja2xCs3BDgjzbwzLVjzHiRFSAs=",
+      "requires": {
+        "browserify-aes": "^1.0.6",
+        "create-hash": "^1.1.2",
+        "create-hmac": "^1.1.4"
+      }
+    },
     "duplexify": {
       "version": "3.6.0",
       "resolved": "https://registry.npmjs.org/duplexify/-/duplexify-3.6.0.tgz",
@@ -2189,7 +2302,6 @@
       "version": "6.4.1",
       "resolved": "https://registry.npmjs.org/elliptic/-/elliptic-6.4.1.tgz",
       "integrity": "sha512-BsXLz5sqX8OHcsh7CqBMztyXARmGQ3LWPtGjJi6DiJHq5C/qvi9P3OqgswKSDftbu8+IoI/QDTAm2fFnQ9SZSQ==",
-      "dev": true,
       "requires": {
         "bn.js": "^4.4.0",
         "brorand": "^1.0.1",
@@ -2402,6 +2514,12 @@
         }
       }
     },
+    "eslint-plugin-chai-friendly": {
+      "version": "0.4.1",
+      "resolved": "https://registry.npmjs.org/eslint-plugin-chai-friendly/-/eslint-plugin-chai-friendly-0.4.1.tgz",
+      "integrity": "sha512-hkpLN7VVoGGsofZjUhcQ+sufC3FgqMJwD0DvAcRfxY1tVRyQyVsqpaKnToPHJQOrRo0FQ0fSEDwW2gr4rsNdGA==",
+      "dev": true
+    },
     "eslint-plugin-es": {
       "version": "1.3.1",
       "resolved": "https://registry.npmjs.org/eslint-plugin-es/-/eslint-plugin-es-1.3.1.tgz",
@@ -2545,6 +2663,44 @@
       "integrity": "sha1-Cr9PHKpbyx96nYrMbepPqqBLrJs=",
       "dev": true
     },
+    "ethereumjs-util": {
+      "version": "5.2.0",
+      "resolved": "https://registry.npmjs.org/ethereumjs-util/-/ethereumjs-util-5.2.0.tgz",
+      "integrity": "sha512-CJAKdI0wgMbQFLlLRtZKGcy/L6pzVRgelIZqRqNbuVFM3K9VEnyfbcvz0ncWMRNCe4kaHWjwRYQcYMucmwsnWA==",
+      "requires": {
+        "bn.js": "^4.11.0",
+        "create-hash": "^1.1.2",
+        "ethjs-util": "^0.1.3",
+        "keccak": "^1.0.2",
+        "rlp": "^2.0.0",
+        "safe-buffer": "^5.1.1",
+        "secp256k1": "^3.0.1"
+      }
+    },
+    "ethereumjs-wallet": {
+      "version": "0.6.2",
+      "resolved": "https://registry.npmjs.org/ethereumjs-wallet/-/ethereumjs-wallet-0.6.2.tgz",
+      "integrity": "sha512-DHEKPV9lYORM7dL8602dkb+AgdfzCYz2lxpdYQoD3OwG355LLDuivW9rGuLpDMCry/ORyBYV6n+QCo/71SwACg==",
+      "requires": {
+        "aes-js": "^3.1.1",
+        "bs58check": "^2.1.2",
+        "ethereumjs-util": "^5.2.0",
+        "hdkey": "^1.0.0",
+        "safe-buffer": "^5.1.2",
+        "scrypt.js": "^0.2.0",
+        "utf8": "^3.0.0",
+        "uuid": "^3.3.2"
+      }
+    },
+    "ethjs-util": {
+      "version": "0.1.6",
+      "resolved": "https://registry.npmjs.org/ethjs-util/-/ethjs-util-0.1.6.tgz",
+      "integrity": "sha512-CUnVOQq7gSpDHZVVrQW8ExxUETWrnrvXYvYz55wOU8Uj4VCgw56XC2B/fVqQN+f7gmrnRHSLVnFAwsCuNwji8w==",
+      "requires": {
+        "is-hex-prefixed": "1.0.0",
+        "strip-hex-prefix": "1.0.0"
+      }
+    },
     "events": {
       "version": "1.1.1",
       "resolved": "https://registry.npmjs.org/events/-/events-1.1.1.tgz",
@@ -2555,7 +2711,6 @@
       "version": "1.0.3",
       "resolved": "https://registry.npmjs.org/evp_bytestokey/-/evp_bytestokey-1.0.3.tgz",
       "integrity": "sha512-/f2Go4TognH/KvCISP7OUsHn85hT9nUkxxA9BEWxFn+Oj9o8ZNLm/40hdlgSLyuOimsrTKLUMEorQexp/aPQeA==",
-      "dev": true,
       "requires": {
         "md5.js": "^1.3.4",
         "safe-buffer": "^5.1.1"
@@ -3563,7 +3718,6 @@
       "version": "3.0.4",
       "resolved": "https://registry.npmjs.org/hash-base/-/hash-base-3.0.4.tgz",
       "integrity": "sha1-X8hoaEfs1zSZQDMZprCj8/auSRg=",
-      "dev": true,
       "requires": {
         "inherits": "^2.0.1",
         "safe-buffer": "^5.0.1"
@@ -3573,12 +3727,21 @@
       "version": "1.1.5",
       "resolved": "https://registry.npmjs.org/hash.js/-/hash.js-1.1.5.tgz",
       "integrity": "sha512-eWI5HG9Np+eHV1KQhisXWwM+4EPPYe5dFX1UZZH7k/E3JzDEazVH+VGlZi6R94ZqImq+A3D1mCEtrFIfg/E7sA==",
-      "dev": true,
       "requires": {
         "inherits": "^2.0.3",
         "minimalistic-assert": "^1.0.1"
       }
     },
+    "hdkey": {
+      "version": "1.1.0",
+      "resolved": "https://registry.npmjs.org/hdkey/-/hdkey-1.1.0.tgz",
+      "integrity": "sha512-E7aU8pNlWUJbXGjTz/+lKf1LkMcA3hUrC5ZleeizrmLSd++kvf8mSOe3q8CmBDA9j4hdfXO5iY6hGiTUCOV2jQ==",
+      "requires": {
+        "coinstring": "^2.0.0",
+        "safe-buffer": "^5.1.1",
+        "secp256k1": "^3.0.1"
+      }
+    },
     "he": {
       "version": "1.1.1",
       "resolved": "https://registry.npmjs.org/he/-/he-1.1.1.tgz",
@@ -3589,7 +3752,6 @@
       "version": "1.0.1",
       "resolved": "https://registry.npmjs.org/hmac-drbg/-/hmac-drbg-1.0.1.tgz",
       "integrity": "sha1-0nRXAQJabHdabFRXk+1QL8DGSaE=",
-      "dev": true,
       "requires": {
         "hash.js": "^1.0.3",
         "minimalistic-assert": "^1.0.0",
@@ -3670,8 +3832,7 @@
     "inherits": {
       "version": "2.0.3",
       "resolved": "https://registry.npmjs.org/inherits/-/inherits-2.0.3.tgz",
-      "integrity": "sha1-Yzwsg+PaQqUC9SRmAiSA9CCCYd4=",
-      "dev": true
+      "integrity": "sha1-Yzwsg+PaQqUC9SRmAiSA9CCCYd4="
     },
     "inquirer": {
       "version": "6.2.0",
@@ -3889,6 +4050,11 @@
         "is-extglob": "^2.1.1"
       }
     },
+    "is-hex-prefixed": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/is-hex-prefixed/-/is-hex-prefixed-1.0.0.tgz",
+      "integrity": "sha1-fY035q135dEnFIkTxXPggtd39VQ="
+    },
     "is-number": {
       "version": "3.0.0",
       "resolved": "https://registry.npmjs.org/is-number/-/is-number-3.0.0.tgz",
@@ -4045,6 +4211,17 @@
       "integrity": "sha1-Hq3nrMASA0rYTiOWdn6tn6VJWCE=",
       "dev": true
     },
+    "keccak": {
+      "version": "1.4.0",
+      "resolved": "https://registry.npmjs.org/keccak/-/keccak-1.4.0.tgz",
+      "integrity": "sha512-eZVaCpblK5formjPjeTBik7TAg+pqnDrMHIffSvi9Lh7PQgM1+hSzakUeZFCk9DVVG0dacZJuaz2ntwlzZUIBw==",
+      "requires": {
+        "bindings": "^1.2.1",
+        "inherits": "^2.0.3",
+        "nan": "^2.2.1",
+        "safe-buffer": "^5.1.0"
+      }
+    },
     "kind-of": {
       "version": "6.0.2",
       "resolved": "https://registry.npmjs.org/kind-of/-/kind-of-6.0.2.tgz",
@@ -4188,7 +4365,6 @@
       "version": "1.3.4",
       "resolved": "https://registry.npmjs.org/md5.js/-/md5.js-1.3.4.tgz",
       "integrity": "sha1-6b296UogpawYsENA/Fdk1bCdkB0=",
-      "dev": true,
       "requires": {
         "hash-base": "^3.0.0",
         "inherits": "^2.0.1"
@@ -4253,14 +4429,12 @@
     "minimalistic-assert": {
       "version": "1.0.1",
       "resolved": "https://registry.npmjs.org/minimalistic-assert/-/minimalistic-assert-1.0.1.tgz",
-      "integrity": "sha512-UtJcAD4yEaGtjPezWuO9wC4nwUnVH/8/Im3yEHQP4b67cXlD/Qr9hdITCU1xDbSEXg2XKNaP8jsReV7vQd00/A==",
-      "dev": true
+      "integrity": "sha512-UtJcAD4yEaGtjPezWuO9wC4nwUnVH/8/Im3yEHQP4b67cXlD/Qr9hdITCU1xDbSEXg2XKNaP8jsReV7vQd00/A=="
     },
     "minimalistic-crypto-utils": {
       "version": "1.0.1",
       "resolved": "https://registry.npmjs.org/minimalistic-crypto-utils/-/minimalistic-crypto-utils-1.0.1.tgz",
-      "integrity": "sha1-9sAMHAsIIkblxNmd+4x8CDsrWCo=",
-      "dev": true
+      "integrity": "sha1-9sAMHAsIIkblxNmd+4x8CDsrWCo="
     },
     "minimatch": {
       "version": "3.0.4",
@@ -4487,9 +4661,7 @@
     "nan": {
       "version": "2.11.0",
       "resolved": "https://registry.npmjs.org/nan/-/nan-2.11.0.tgz",
-      "integrity": "sha512-F4miItu2rGnV2ySkXOQoA8FKz/SR2Q2sWP0sbTxNxz/tuokeC8WxOhPMcwi0qIyGtVn/rrSeLbvVkznqCdwYnw==",
-      "dev": true,
-      "optional": true
+      "integrity": "sha512-F4miItu2rGnV2ySkXOQoA8FKz/SR2Q2sWP0sbTxNxz/tuokeC8WxOhPMcwi0qIyGtVn/rrSeLbvVkznqCdwYnw=="
     },
     "nanomatch": {
       "version": "1.2.13",
@@ -4880,7 +5052,6 @@
       "version": "3.0.16",
       "resolved": "https://registry.npmjs.org/pbkdf2/-/pbkdf2-3.0.16.tgz",
       "integrity": "sha512-y4CXP3thSxqf7c0qmOF+9UeOTrifiVTIM+u7NWlq+PRsHbr7r7dpCmvzrZxa96JJUNi0Y5w9VqG5ZNeCVMoDcA==",
-      "dev": true,
       "requires": {
         "create-hash": "^1.1.2",
         "create-hmac": "^1.1.4",
@@ -5041,7 +5212,6 @@
       "version": "2.0.6",
       "resolved": "https://registry.npmjs.org/randombytes/-/randombytes-2.0.6.tgz",
       "integrity": "sha512-CIQ5OFxf4Jou6uOKe9t1AOgqpeU5fd70A8NPdHSGeYXqXsPe6peOwI0cUl88RWZ6sP1vPMV3avd/R6cZ5/sP1A==",
-      "dev": true,
       "requires": {
         "safe-buffer": "^5.1.0"
       }
@@ -5311,12 +5481,19 @@
       "version": "2.0.2",
       "resolved": "https://registry.npmjs.org/ripemd160/-/ripemd160-2.0.2.tgz",
       "integrity": "sha512-ii4iagi25WusVoiC4B4lq7pbXfAp3D9v5CwfkY33vffw2+pkDjY1D8GaN7spsxvCSx8dkPqOZCEZyfxcmJG2IA==",
-      "dev": true,
       "requires": {
         "hash-base": "^3.0.0",
         "inherits": "^2.0.1"
       }
     },
+    "rlp": {
+      "version": "2.1.0",
+      "resolved": "https://registry.npmjs.org/rlp/-/rlp-2.1.0.tgz",
+      "integrity": "sha512-93U7IKH5j7nmXFVg19MeNBGzQW5uXW1pmCuKY8veeKIhYTE32C2d0mOegfiIAfXcHOKJjjPlJisn8iHDF5AezA==",
+      "requires": {
+        "safe-buffer": "^5.1.1"
+      }
+    },
     "run-async": {
       "version": "2.3.0",
       "resolved": "https://registry.npmjs.org/run-async/-/run-async-2.3.0.tgz",
@@ -5347,8 +5524,7 @@
     "safe-buffer": {
       "version": "5.1.2",
       "resolved": "https://registry.npmjs.org/safe-buffer/-/safe-buffer-5.1.2.tgz",
-      "integrity": "sha512-Gd2UZBJDkXlY7GbJxfsE8/nvKkUEU1G38c1siN6QP6a9PT9MmHB8GnpscSmMJSoF8LOIrt8ud/wPtojys4G6+g==",
-      "dev": true
+      "integrity": "sha512-Gd2UZBJDkXlY7GbJxfsE8/nvKkUEU1G38c1siN6QP6a9PT9MmHB8GnpscSmMJSoF8LOIrt8ud/wPtojys4G6+g=="
     },
     "safe-regex": {
       "version": "1.1.0",
@@ -5375,6 +5551,46 @@
         "ajv-keywords": "^3.1.0"
       }
     },
+    "scrypt": {
+      "version": "6.0.3",
+      "resolved": "https://registry.npmjs.org/scrypt/-/scrypt-6.0.3.tgz",
+      "integrity": "sha1-BOAUpWgrU/pQwtXM4WfXGcBthw0=",
+      "requires": {
+        "nan": "^2.0.8"
+      }
+    },
+    "scrypt.js": {
+      "version": "0.2.0",
+      "resolved": "https://registry.npmjs.org/scrypt.js/-/scrypt.js-0.2.0.tgz",
+      "integrity": "sha1-r40UZbcemZARC+38WTuUeeA6ito=",
+      "requires": {
+        "scrypt": "^6.0.2",
+        "scryptsy": "^1.2.1"
+      }
+    },
+    "scryptsy": {
+      "version": "1.2.1",
+      "resolved": "https://registry.npmjs.org/scryptsy/-/scryptsy-1.2.1.tgz",
+      "integrity": "sha1-oyJfpLJST4AnAHYeKFW987LZIWM=",
+      "requires": {
+        "pbkdf2": "^3.0.3"
+      }
+    },
+    "secp256k1": {
+      "version": "3.5.2",
+      "resolved": "https://registry.npmjs.org/secp256k1/-/secp256k1-3.5.2.tgz",
+      "integrity": "sha512-iin3kojdybY6NArd+UFsoTuapOF7bnJNf2UbcWXaY3z+E1sJDipl60vtzB5hbO/uquBu7z0fd4VC4Irp+xoFVQ==",
+      "requires": {
+        "bindings": "^1.2.1",
+        "bip66": "^1.1.3",
+        "bn.js": "^4.11.3",
+        "create-hash": "^1.1.2",
+        "drbg.js": "^1.0.1",
+        "elliptic": "^6.2.3",
+        "nan": "^2.2.1",
+        "safe-buffer": "^5.1.0"
+      }
+    },
     "semver": {
       "version": "5.5.1",
       "resolved": "https://registry.npmjs.org/semver/-/semver-5.5.1.tgz",
@@ -5432,7 +5648,6 @@
       "version": "2.4.11",
       "resolved": "https://registry.npmjs.org/sha.js/-/sha.js-2.4.11.tgz",
       "integrity": "sha512-QMEp5B7cftE7APOjk5Y6xgrbWu+WkLVQwk8JNjZ8nKRciZaByEW6MubieAiToS7+dwvrjGhH8jRXz3MVd0AYqQ==",
-      "dev": true,
       "requires": {
         "inherits": "^2.0.1",
         "safe-buffer": "^5.0.1"
@@ -5803,6 +6018,14 @@
       "integrity": "sha1-u0P/VZim6wXYm1n80SnJgzE2Br8=",
       "dev": true
     },
+    "strip-hex-prefix": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/strip-hex-prefix/-/strip-hex-prefix-1.0.0.tgz",
+      "integrity": "sha1-DF8VX+8RUTczd96du1iNoFUA428=",
+      "requires": {
+        "is-hex-prefixed": "1.0.0"
+      }
+    },
     "strip-json-comments": {
       "version": "2.0.1",
       "resolved": "https://registry.npmjs.org/strip-json-comments/-/strip-json-comments-2.0.1.tgz",
@@ -6094,6 +6317,11 @@
         "imurmurhash": "^0.1.4"
       }
     },
+    "unorm": {
+      "version": "1.4.1",
+      "resolved": "https://registry.npmjs.org/unorm/-/unorm-1.4.1.tgz",
+      "integrity": "sha1-NkIA1fE2RsqLzURJAnEzVhR5IwA="
+    },
     "unset-value": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/unset-value/-/unset-value-1.0.0.tgz",
@@ -6179,6 +6407,11 @@
       "integrity": "sha512-cwESVXlO3url9YWlFW/TA9cshCEhtu7IKJ/p5soJ/gGpj7vbvFrAY/eIioQ6Dw23KjZhYgiIo8HOs1nQ2vr/oQ==",
       "dev": true
     },
+    "utf8": {
+      "version": "3.0.0",
+      "resolved": "https://registry.npmjs.org/utf8/-/utf8-3.0.0.tgz",
+      "integrity": "sha512-E8VjFIQ/TyQgp+TZfS6l8yp/xWppSAHzidGiRrqe4bK4XP9pTRyKFgGJpO3SN7zdX4DeomTrwaseCHovfpFcqQ=="
+    },
     "util": {
       "version": "0.10.4",
       "resolved": "https://registry.npmjs.org/util/-/util-0.10.4.tgz",
@@ -6204,6 +6437,11 @@
         "object.getownpropertydescriptors": "^2.0.3"
       }
     },
+    "uuid": {
+      "version": "3.3.2",
+      "resolved": "https://registry.npmjs.org/uuid/-/uuid-3.3.2.tgz",
+      "integrity": "sha512-yXJmeNaw3DnnKAOKJE51sL/ZaYfWJRl1pK9dr19YFCu0ObS231AB1/LbqTKRAQ5kw8A90rA6fr4riOUpTZvQZA=="
+    },
     "v8-compile-cache": {
       "version": "2.0.2",
       "resolved": "https://registry.npmjs.org/v8-compile-cache/-/v8-compile-cache-2.0.2.tgz",
@@ -6323,6 +6561,12 @@
         }
       }
     },
+    "webpack-node-externals": {
+      "version": "1.7.2",
+      "resolved": "https://registry.npmjs.org/webpack-node-externals/-/webpack-node-externals-1.7.2.tgz",
+      "integrity": "sha512-ajerHZ+BJKeCLviLUUmnyd5B4RavLF76uv3cs6KNuO8W+HuQaEs0y0L7o40NQxdPy5w0pcv8Ew7yPUAQG0UdCg==",
+      "dev": true
+    },
     "webpack-sources": {
       "version": "1.1.0",
       "resolved": "https://registry.npmjs.org/webpack-sources/-/webpack-sources-1.1.0.tgz",
diff --git a/package.json b/package.json
index 9544477..fd664c3 100644
--- a/package.json
+++ b/package.json
@@ -12,12 +12,16 @@
   "author": "Chaintope Inc.",
   "devDependencies": {
     "@babel/core": "^7.0.0",
+    "@babel/plugin-transform-runtime": "^7.0.0",
+    "@babel/polyfill": "^7.0.0",
     "@babel/preset-env": "^7.0.0",
+    "@babel/runtime": "^7.0.0",
     "babel-eslint": "^9.0.0",
     "babel-loader": "^8.0.2",
     "chai": "^4.1.2",
     "eslint": "^5.5.0",
     "eslint-config-standard": "^12.0.0",
+    "eslint-plugin-chai-friendly": "^0.4.1",
     "eslint-plugin-import": "^2.14.0",
     "eslint-plugin-mocha": "^5.2.0",
     "eslint-plugin-node": "^7.0.1",
@@ -26,6 +30,11 @@
     "mocha": "^5.2.0",
     "mocha-webpack": "^2.0.0-beta.0",
     "webpack": "^4.17.1",
-    "webpack-cli": "^3.1.0"
+    "webpack-cli": "^3.1.0",
+    "webpack-node-externals": "^1.7.2"
+  },
+  "dependencies": {
+    "bip39": "^2.5.0",
+    "ethereumjs-wallet": "^0.6.2"
   }
 }
diff --git a/test/masa.spec.js b/test/masa.spec.js
index 2be41fc..c2ad5c2 100644
--- a/test/masa.spec.js
+++ b/test/masa.spec.js
@@ -1,9 +1,35 @@
 import masa from '../lib/masa'
-var assert = require('assert')
+import { expect } from 'chai'
 
 describe('masa.js', () => {
-  it('should load', () => {
-    console.log(masa)
-    assert(masa)
+  describe('init', () => {
+    it('should load', () => {
+      expect(masa).to.be.ok
+    })
+  })
+  describe('masa point', () => {
+    it('get masa point amount', async() => {
+      expect(await masa.point.amountOf('0xaaaaaaaaaaaaaaaaaaaabbbbbbbbbbbbbbbbbbbb')).to.be.equal(500)
+      expect(await masa.point.amountOf('0x6861766520636f696e20697300000000000000b8')).to.be.equal(200)
+    })
+    it('get community masa point amount', async() => {
+      expect(await masa.point.communityAmountOf('0x6861766520636f696e20697300000000000000b8', 5)).to.be.equal(200)
+    })
+    it('masa.point.feedback is not support.', () => {
+      expect(function() {
+        masa.point.feedback('0x6861766520636f696e20697300000000000000b8', 'Challenge Caravan', 1, '')
+      }).to.throw('Not support function. Please use MasaTx.')
+    })
+  })
+  describe('masa coin', () => {
+    it('balanceOf', async() => {
+      const balance = await masa.coin.balanceOf('0xdaF8F49A3671082ED2ab0b67ecB7f0182fAEAb6C')
+      return expect(balance).to.be.equal(100)
+    })
+    it('unsupport transfer.', () => {
+      expect(function() {
+        masa.coin.transfer('0xdaF8F49A3671082ED2ab0b67ecB7f0182fAEAb6C', 20)
+      }).to.throw('Not support function. Please use MasaTx.')
+    })
   })
 })
diff --git a/test/masa_tx.spec.js b/test/masa_tx.spec.js
new file mode 100644
index 0000000..dd7256e
--- /dev/null
+++ b/test/masa_tx.spec.js
@@ -0,0 +1,71 @@
+import { expect } from 'chai'
+import MasaTx from '../lib/masa_tx'
+import { GANACHE_MNEMONIC } from './util'
+
+describe('MasaTx', () => {
+  describe('init', () => {
+    it('should load', () => {
+      expect(MasaTx).to.be.ok
+    })
+    it('create with generate Wallet', () => {
+      const masaTx = new MasaTx()
+      expect(masaTx).to.be.ok
+      expect(masaTx.wallet.mnemonic).to.be.a('string')
+      expect(masaTx.wallet.mnemonic).to.be.not.equal(GANACHE_MNEMONIC)
+    })
+    it('create with restore Wallet', () => {
+      const masaTx = new MasaTx(GANACHE_MNEMONIC)
+      expect(masaTx).to.be.ok
+      expect(masaTx.wallet.mnemonic).to.be.a('string')
+      expect(masaTx.wallet.mnemonic).to.be.equal(GANACHE_MNEMONIC)
+    })
+  })
+  describe('masaPoint', () => {
+    let masaTx
+    beforeEach(() => {
+      masaTx = new MasaTx()
+    })
+    it('create feedback transaction', async() => {
+      const feedbackTx = await masaTx.point.feedback('0xdaF8F49A3671082ED2ab0b67ecB7f0182fAEAb6C', 'Challenge Caravan', 1, '')
+      expect(feedbackTx).to.be.a('transaction')
+    })
+    it('unsupport amountOf', () => {
+      expect(function() {
+        masaTx.point.amountOf('0x6861766520636f696e20697300000000000000b8')
+      }).to.throw('Not support function. Please use Masa.')
+    })
+    it('unsupport communityAmountOf', () => {
+      expect(function() {
+        masaTx.point.communityAmountOf('0x6861766520636f696e20697300000000000000b8', 'chare cara')
+      }).to.throw('Not support function. Please use Masa.')
+    })
+  })
+  describe('masaCoin', () => {
+    let masaTx
+    beforeEach(() => {
+      masaTx = new MasaTx()
+    })
+    it('create transfer transaction', async() => {
+      const transferTx = await masaTx.coin.transfer('0xdaF8F49A3671082ED2ab0b67ecB7f0182fAEAb6C', 100)
+      expect(transferTx).to.be.a('transaction')
+    })
+    it('unsupport balanceOf', () => {
+      return masaTx.coin
+        .balanceOf('0xdaF8F49A3671082ED2ab0b67ecB7f0182fAEAb6C').then(balance => {
+          expect.fail('not happend error')
+        }).catch(e => {
+          expect(e.message).to.be.equal('Not support function. Please use Masa.')
+        })
+    })
+  })
+  describe('community', () => {
+    let masaTx
+    beforeEach(() => {
+      masaTx = new MasaTx()
+    })
+    it('create create transaction', async() => {
+      const createTx = await masaTx.community.create('SDGs')
+      expect(createTx).to.be.a('transaction')
+    })
+  })
+})
diff --git a/test/util.js b/test/util.js
new file mode 100644
index 0000000..791aadd
--- /dev/null
+++ b/test/util.js
@@ -0,0 +1,5 @@
+const GANACHE_MNEMONIC = 'special client interest guess wrist bring rack hockey tip divert three toe'
+
+export {
+  GANACHE_MNEMONIC
+}
diff --git a/test/wallet.spec.js b/test/wallet.spec.js
new file mode 100644
index 0000000..ee5dea6
--- /dev/null
+++ b/test/wallet.spec.js
@@ -0,0 +1,51 @@
+import Wallet from '../lib/wallet'
+import { expect } from 'chai'
+import { GANACHE_MNEMONIC } from './util'
+
+describe('wallet.js', () => {
+  it('should load', () => {
+    expect(Wallet).to.be.ok
+  })
+  describe('initialize', function() {
+    it('generate mnemonic', () => {
+      const mnemonic = Wallet.generateMnemonic()
+      expect(mnemonic).to.be.a('string')
+      expect(mnemonic.split(' ')).to.have.lengthOf(12)
+    })
+    it('create wallet', function() {
+      this.timeout(10000)
+      const wallet = new Wallet(GANACHE_MNEMONIC)
+      expect(wallet).to.be.ok
+      expect(wallet).to.be.a('wallet')
+    })
+    it('failed. if specify undefined', () => {
+      expect(function() {
+        return new Wallet(undefined)
+      }).to.throw('invalid mnemonic!')
+    })
+    it('failed. if specify empty string', () => {
+      expect(function() {
+        return new Wallet('')
+      }).to.throw('invalid mnemonic!')
+    })
+  })
+  describe('wallet functions', function() {
+    this.timeout(10000)
+    let wallet
+    before(function() {
+      wallet = new Wallet(GANACHE_MNEMONIC)
+    })
+    it('check cat reget mnemonic', () => {
+      expect(wallet.mnemonic).to.be.equal(GANACHE_MNEMONIC)
+    })
+    it('check privateKey', () => {
+      expect(wallet.privateKey.toString('hex')).to.be.equal('4d8d0ece9fd220f7fb7f53f71e636ac377aa8bab4e5c8e601e515a625917134e')
+    })
+    it('check publicKey', () => {
+      expect(wallet.publicKey.toString('hex')).to.be.equal('06d40dcd8748c724e20405eb837a6fc02eea32492dbea17b852ae1dba8500ba1193d843bb694f8d0fafab4007f213607a85297ebf505b2e9a1708b6d3af25553')
+    })
+    it('check address', () => {
+      expect(wallet.address).to.be.equal('0xdaf8f49a3671082ed2ab0b67ecb7f0182faeab6c')
+    })
+  })
+})
diff --git a/webpack.config.js b/webpack.config.js
index 0f67bb0..220f91c 100644
--- a/webpack.config.js
+++ b/webpack.config.js
@@ -1,7 +1,10 @@
-const path = require('path');
+const path = require('path')
+const nodeExternals = require('webpack-node-externals')
 
 module.exports = {
-  entry: './index.js',
+  target: 'node',
+  externals: [nodeExternals()],
+  entry: ['./index.js'],
   mode: 'development',
   output: {
     filename: 'masa.js',
@@ -13,12 +16,13 @@ module.exports = {
         test: /\.js$/,
         exclude: /node_modules/,
         use: {
-          loader: "babel-loader",
+          loader: 'babel-loader',
           options: {
-            presets: ['@babel/preset-env']
+            presets: ['@babel/preset-env'],
+            plugins: ['@babel/transform-runtime']
           }
         }
       }
     ]
   }
-};
+}