diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5bd3cbe..4404844 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,7 +2,11 @@
 
 All notable changes to this project will be documented in this file.
 
-## [4.0.0] - 2019-05-22
+## [4.0.1] - 2019-06-23
+
+- Fix `web3x-codegen` path resolution bug.
+
+## [4.0.0] - 2019-06-23
 
 - Major project restructure.
 - `web3x-codegen` is its own package.
@@ -159,6 +163,7 @@ All notable changes to this project will be documented in this file.
 
 - Initial release of Typescript port from web3.js.
 
+[4.0.1]: https://github.com/xf00f/web3x/compare/v4.0.0...v4.0.1
 [4.0.0]: https://github.com/xf00f/web3x/compare/v3.0.11...v4.0.0
 [3.0.11]: https://github.com/xf00f/web3x/compare/v3.0.10...v3.0.11
 [3.0.10]: https://github.com/xf00f/web3x/compare/v3.0.9...v3.0.10
diff --git a/version.json b/version.json
index 29d7b50..581ef58 100644
--- a/version.json
+++ b/version.json
@@ -1 +1 @@
-"4.0.0"
+"4.0.1"
diff --git a/web3x-codegen/package.json b/web3x-codegen/package.json
index 32bb674..610570f 100644
--- a/web3x-codegen/package.json
+++ b/web3x-codegen/package.json
@@ -1,6 +1,6 @@
 {
   "name": "web3x-codegen",
-  "version": "4.0.0",
+  "version": "4.0.1",
   "license": "MIT",
   "description": "Contract interface code generator for web3x.",
   "repository": {
diff --git a/web3x-codegen/src/index.ts b/web3x-codegen/src/index.ts
index 5c52eab..02cef35 100644
--- a/web3x-codegen/src/index.ts
+++ b/web3x-codegen/src/index.ts
@@ -500,8 +500,8 @@ export async function makeAndWriteFiles(
 }
 
 export function getWeb3xPath() {
-  const pkg = JSON.parse(fs.readFileSync(__dirname + '/../package.json').toString());
-  return pkg.name;
+  const pkg = JSON.parse(fs.readFileSync('package.json').toString());
+  return { ...pkg.dependencies, ...pkg.devDependencies }['web3x-es'] ? 'web3x-es' : 'web3x';
 }
 
 async function main() {
diff --git a/web3x-node-example/package.json b/web3x-node-example/package.json
index 7e1b7fd..2bc3d47 100644
--- a/web3x-node-example/package.json
+++ b/web3x-node-example/package.json
@@ -27,6 +27,7 @@
   "devDependencies": {
     "@types/jest": "^23.3.12",
     "jest": "^23.6.0",
-    "nodemon": "^1.18.5"
+    "nodemon": "^1.18.5",
+    "web3x-codegen": "^4.0.0"
   }
 }
diff --git a/web3x-node-example/yarn.lock b/web3x-node-example/yarn.lock
index e6bc60c..bb3c761 100644
--- a/web3x-node-example/yarn.lock
+++ b/web3x-node-example/yarn.lock
@@ -30,11 +30,6 @@
   dependencies:
     defer-to-connect "^1.0.1"
 
-"@types/abstract-leveldown@*":
-  version "5.0.1"
-  resolved "https://registry.yarnpkg.com/@types/abstract-leveldown/-/abstract-leveldown-5.0.1.tgz#3c7750d0186b954c7f2d2f6acc8c3c7ba0c3412e"
-  integrity sha512-wYxU3kp5zItbxKmeRYCEplS2MW7DzyBnxPGj+GJVHZEUZiK/nn5Ei1sUFgURDh+X051+zsGe28iud3oHjrYWQQ==
-
 "@types/bn.js@^4.11.2":
   version "4.11.3"
   resolved "https://registry.yarnpkg.com/@types/bn.js/-/bn.js-4.11.3.tgz#0f09e53e98659b007d7019261ddab9178135df38"
@@ -52,15 +47,6 @@
   resolved "https://registry.yarnpkg.com/@types/jest/-/jest-23.3.12.tgz#7e0ced251fa94c3bc2d1023d4b84b2992fa06376"
   integrity sha512-/kQvbVzdEpOq4tEWT79yAHSM4nH4xMlhJv2GrLVQt4Qmo8yYsPdioBM1QpN/2GX1wkfMnyXvdoftvLUr0LBj7Q==
 
-"@types/levelup@^3.1.0":
-  version "3.1.0"
-  resolved "https://registry.yarnpkg.com/@types/levelup/-/levelup-3.1.0.tgz#e04f6a8eaf707f88d7c6e043a9067dda431f4538"
-  integrity sha512-Y2SC5PskYsE8+dELuWLCMG+UcUrkhhIz5wV55yX73AAVqr3kDXLYlj6k/vuchXUt1L1b/P1Frt4Dcc3WmWcbLA==
-  dependencies:
-    "@types/abstract-leveldown" "*"
-    "@types/events" "*"
-    "@types/node" "*"
-
 "@types/node@*":
   version "10.12.18"
   resolved "https://registry.yarnpkg.com/@types/node/-/node-10.12.18.tgz#1d3ca764718915584fcd9f6344621b7672665c67"
@@ -89,21 +75,6 @@ abbrev@1:
   resolved "https://registry.yarnpkg.com/abbrev/-/abbrev-1.1.1.tgz#f8f2c887ad10bf67f634f005b6987fed3179aac8"
   integrity sha512-nne9/IiQ/hzIhY6pdDnbBtz7DjPTKrY00P/zvPSm5pOFkl6xuGrGnXn/VtTNNfNtAfZ9/1RtehkszU9qcTii0Q==
 
-abstract-leveldown@^5.0.0, abstract-leveldown@~5.0.0:
-  version "5.0.0"
-  resolved "https://registry.npmjs.org/abstract-leveldown/-/abstract-leveldown-5.0.0.tgz#f7128e1f86ccabf7d2893077ce5d06d798e386c6"
-  integrity sha512-5mU5P1gXtsMIXg65/rsYGsi93+MlogXZ9FA8JnwKurHQg64bfXwGYVdVdijNTVNOlAsuIiOwHdvFFD5JqCJQ7A==
-  dependencies:
-    xtend "~4.0.0"
-
-abstract-leveldown@~6.0.0, abstract-leveldown@~6.0.1:
-  version "6.0.1"
-  resolved "https://registry.npmjs.org/abstract-leveldown/-/abstract-leveldown-6.0.1.tgz#2d5dd4c26799a38b7ca52026b3b7e8e5283bd165"
-  integrity sha512-8ccQIKHwmh7rIRWvKGgSTM2LByLWpLZgAYRjDNOh1ZTXvlR0gtm2Ir7aD8rEUre8DMllchJJTAZhhN5aUBN7XA==
-  dependencies:
-    level-concat-iterator "~2.0.0"
-    xtend "~4.0.0"
-
 accepts@~1.3.5:
   version "1.3.5"
   resolved "https://registry.yarnpkg.com/accepts/-/accepts-1.3.5.tgz#eb777df6011723a3b14e8a72c0805c8e86746bd2"
@@ -300,13 +271,6 @@ async@^2.1.4, async@^2.5.0:
   dependencies:
     lodash "^4.17.10"
 
-async@^2.6.1:
-  version "2.6.2"
-  resolved "https://registry.npmjs.org/async/-/async-2.6.2.tgz#18330ea7e6e313887f5d2f2a904bac6fe4dd5381"
-  integrity sha512-H1qVYh1MYhEEFLsP97cVKqCGo7KfCyTt6uEWqsTBr9SO84oK9Uwbyd/yCW+6rKJLHksBNUVWZDAjfS+Ccx0Bbg==
-  dependencies:
-    lodash "^4.17.11"
-
 asynckit@^0.4.0:
   version "0.4.0"
   resolved "https://registry.yarnpkg.com/asynckit/-/asynckit-0.4.0.tgz#c79ed97f7f34cb8f2ba1bc9790bcc366474b4b79"
@@ -523,13 +487,6 @@ bcrypt-pbkdf@^1.0.0:
   dependencies:
     tweetnacl "^0.14.3"
 
-bigint-buffer@^1.1.2:
-  version "1.1.2"
-  resolved "https://registry.npmjs.org/bigint-buffer/-/bigint-buffer-1.1.2.tgz#b7edfaf3a88d0767aed7edc671d6bae4b1021575"
-  integrity sha512-gof9NgbodUgCXD2aUHfUKk5KUDk6/zPlwE+YYpRM2t7zS0K/6WipJFWfziIY+EavxFDuGUnuuQQzzvNcckPKNA==
-  dependencies:
-    bindings "^1.3.0"
-
 binary-extensions@^1.0.0:
   version "1.12.0"
   resolved "https://registry.yarnpkg.com/binary-extensions/-/binary-extensions-1.12.0.tgz#c2d780f53d45bba8317a8902d4ceeaf3a6385b14"
@@ -540,13 +497,6 @@ bindings@^1.2.1:
   resolved "https://registry.yarnpkg.com/bindings/-/bindings-1.3.1.tgz#21fc7c6d67c18516ec5aaa2815b145ff77b26ea5"
   integrity sha512-i47mqjF9UbjxJhxGf+pZ6kSxrnI3wBLlnGI2ArWJ4r0VrvDS7ZYXkprq/pLaBWYq4GM0r4zdHY+NNRqEMU7uew==
 
-bindings@^1.3.0:
-  version "1.4.0"
-  resolved "https://registry.npmjs.org/bindings/-/bindings-1.4.0.tgz#909efa49f2ebe07ecd3cb136778f665052040127"
-  integrity sha512-7znEVX22Djn+nYjxCWKDne0RRloa9XfYa84yk3s+HkE3LpDYZmhArYr9O9huBoHY3/oXispx5LorIX7Sl2CgSQ==
-  dependencies:
-    file-uri-to-path "1.0.0"
-
 bip39@^2.5.0:
   version "2.5.0"
   resolved "https://registry.yarnpkg.com/bip39/-/bip39-2.5.0.tgz#51cbd5179460504a63ea3c000db3f787ca051235"
@@ -578,7 +528,7 @@ bluebird@^3.5.0:
   resolved "https://registry.yarnpkg.com/bluebird/-/bluebird-3.5.3.tgz#7d01c6f9616c9a51ab0f8c549a79dfe6ec33efa7"
   integrity sha512-/qKPUQlaW1OyR51WeCPBvRnAlnZFUJkCSG5HzGnuIqhgyJtF+T94lFnn33eiazjRm2LAHVy2guNnaq48X9SJuw==
 
-bn.js@^4.11.0, bn.js@^4.11.1, bn.js@^4.11.3, bn.js@^4.11.6, bn.js@^4.11.8, bn.js@^4.4.0:
+bn.js@^4.11.1, bn.js@^4.11.3, bn.js@^4.11.6, bn.js@^4.11.8, bn.js@^4.4.0:
   version "4.11.8"
   resolved "https://registry.yarnpkg.com/bn.js/-/bn.js-4.11.8.tgz#2cde09eb5ee341f484746bb0309b3253b1b1442f"
   integrity sha512-ItfYfPLkWHUjckQCk8xC+LwxgK8NYcXywGigJgSwOP8Y2iyWT4f2vsZnoOXTTbo+o5yXmIUJ4gn5538SO5S3gA==
@@ -1222,22 +1172,6 @@ defer-to-connect@^1.0.1:
   resolved "https://registry.yarnpkg.com/defer-to-connect/-/defer-to-connect-1.0.1.tgz#41ec1dd670dc4c6dcbe7e54c9e44d784d025fe63"
   integrity sha512-2e0FJesseUqQj671gvZWfUyxpnFx/5n4xleamlpCD3U6Fm5dh5qzmmLNxNhtmHF06+SYVHH8QU6FACffYTnj0Q==
 
-deferred-leveldown@~4.0.0:
-  version "4.0.2"
-  resolved "https://registry.npmjs.org/deferred-leveldown/-/deferred-leveldown-4.0.2.tgz#0b0570087827bf480a23494b398f04c128c19a20"
-  integrity sha512-5fMC8ek8alH16QiV0lTCis610D1Zt1+LA4MS4d63JgS32lrCjTFDUFz2ao09/j2I4Bqb5jL4FZYwu7Jz0XO1ww==
-  dependencies:
-    abstract-leveldown "~5.0.0"
-    inherits "^2.0.3"
-
-deferred-leveldown@~5.0.0:
-  version "5.0.0"
-  resolved "https://registry.npmjs.org/deferred-leveldown/-/deferred-leveldown-5.0.0.tgz#28717f5da3c4e4dc42c367338e9596f04c5cb310"
-  integrity sha512-QtTcNm2PX7elim5bGl+i3px2kVbpI49BV+Q62CFh0AaMlrdlbMXyozBg31p2zJqAAT35FUw4eccC+drr3D0+vQ==
-  dependencies:
-    abstract-leveldown "~6.0.0"
-    inherits "^2.0.3"
-
 define-properties@^1.1.2:
   version "1.1.3"
   resolved "https://registry.yarnpkg.com/define-properties/-/define-properties-1.1.3.tgz#cf88da6cbee26fe6db7094f61d870cbd84cee9f1"
@@ -1373,17 +1307,6 @@ encodeurl@~1.0.2:
   resolved "https://registry.yarnpkg.com/encodeurl/-/encodeurl-1.0.2.tgz#ad3ff4c86ec2d029322f5a02c3a9a606c95b3f59"
   integrity sha1-rT/0yG7C0CkyL1oCw6mmBslbP1k=
 
-encoding-down@~5.0.0:
-  version "5.0.4"
-  resolved "https://registry.npmjs.org/encoding-down/-/encoding-down-5.0.4.tgz#1e477da8e9e9d0f7c8293d320044f8b2cd8e9614"
-  integrity sha512-8CIZLDcSKxgzT+zX8ZVfgNbu8Md2wq/iqa1Y7zyVR18QBEAc0Nmzuvj/N5ykSKpfGzjM8qxbaFntLPwnVoUhZw==
-  dependencies:
-    abstract-leveldown "^5.0.0"
-    inherits "^2.0.3"
-    level-codec "^9.0.0"
-    level-errors "^2.0.0"
-    xtend "^4.0.1"
-
 end-of-stream@^1.0.0, end-of-stream@^1.1.0:
   version "1.4.1"
   resolved "https://registry.yarnpkg.com/end-of-stream/-/end-of-stream-1.4.1.tgz#ed29634d19baba463b6ce6b80a37213eab71ec43"
@@ -1391,13 +1314,6 @@ end-of-stream@^1.0.0, end-of-stream@^1.1.0:
   dependencies:
     once "^1.4.0"
 
-errno@~0.1.1:
-  version "0.1.7"
-  resolved "https://registry.npmjs.org/errno/-/errno-0.1.7.tgz#4684d71779ad39af177e3f007996f7c67c852618"
-  integrity sha512-MfrRBDWzIWifgq6tJj60gkAwtLNb6sQPlcFrSOflcP1aFmmruKQ2wRnze/8V6kgyz7H3FF8Npzv78mZ7XLLflg==
-  dependencies:
-    prr "~1.0.1"
-
 error-ex@^1.2.0:
   version "1.3.2"
   resolved "https://registry.yarnpkg.com/error-ex/-/error-ex-1.3.2.tgz#b4ac40648107fdcdcfae242f428bea8a14d4f1bf"
@@ -1486,27 +1402,6 @@ eth-lib@^0.1.26:
     ws "^3.0.0"
     xhr-request-promise "^0.1.2"
 
-ethereumjs-util@^5.2.0:
-  version "5.2.0"
-  resolved "https://registry.npmjs.org/ethereumjs-util/-/ethereumjs-util-5.2.0.tgz#3e0c0d1741471acf1036052d048623dee54ad642"
-  integrity sha512-CJAKdI0wgMbQFLlLRtZKGcy/L6pzVRgelIZqRqNbuVFM3K9VEnyfbcvz0ncWMRNCe4kaHWjwRYQcYMucmwsnWA==
-  dependencies:
-    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"
-
-ethjs-util@^0.1.3:
-  version "0.1.6"
-  resolved "https://registry.npmjs.org/ethjs-util/-/ethjs-util-0.1.6.tgz#f308b62f185f9fe6237132fb2a9818866a5cd536"
-  integrity sha512-CUnVOQq7gSpDHZVVrQW8ExxUETWrnrvXYvYz55wOU8Uj4VCgw56XC2B/fVqQN+f7gmrnRHSLVnFAwsCuNwji8w==
-  dependencies:
-    is-hex-prefixed "1.0.0"
-    strip-hex-prefix "1.0.0"
-
 evp_bytestokey@^1.0.3:
   version "1.0.3"
   resolved "https://registry.yarnpkg.com/evp_bytestokey/-/evp_bytestokey-1.0.3.tgz#7fcbdb198dc71959432efe13842684e0525acb02"
@@ -1710,11 +1605,6 @@ file-type@^6.1.0:
   resolved "https://registry.yarnpkg.com/file-type/-/file-type-6.2.0.tgz#e50cd75d356ffed4e306dc4f5bcf52a79903a919"
   integrity sha512-YPcTBDV+2Tm0VqjybVd32MHdlEGAtuxS3VAYsumFokDSMG+ROT5wawGlnHDoz7bfMcMDt9hxuXvXwoKUx2fkOg==
 
-file-uri-to-path@1.0.0:
-  version "1.0.0"
-  resolved "https://registry.npmjs.org/file-uri-to-path/-/file-uri-to-path-1.0.0.tgz#553a7b8446ff6f684359c445f1e37a05dacc33dd"
-  integrity sha512-0Zt+s3L7Vf1biwWZ29aARiVYLx7iMGnEUl9x33fbB/j3jR81u/O2LbqK+Bm1CDSNDKVtJ/YjwY7TUd5SkeLQLw==
-
 filename-regex@^2.0.0:
   version "2.0.1"
   resolved "https://registry.yarnpkg.com/filename-regex/-/filename-regex-2.0.1.tgz#c1c4b9bee3e09725ddb106b75c1e301fe2f18b26"
@@ -1875,11 +1765,6 @@ function-bind@^1.1.1:
   resolved "https://registry.yarnpkg.com/function-bind/-/function-bind-1.1.1.tgz#a56899d3ea3c9bab874bb9773b7c5ede92f4895d"
   integrity sha512-yIovAzMX49sF8Yl58fSCWJ5svSLuaibPxXQJFLmBObTuCr0Mf1KiPopGM9NiFjiYBCbfaa2Fh6breQ6ANVTI0A==
 
-functional-red-black-tree@~1.0.1:
-  version "1.0.1"
-  resolved "https://registry.npmjs.org/functional-red-black-tree/-/functional-red-black-tree-1.0.1.tgz#1b0ab3bd553b2a0d6399d29c0e3ea0b252078327"
-  integrity sha1-GwqzvVU7Kg1jmdKcDj6gslIHgyc=
-
 gauge@~2.7.3:
   version "2.7.4"
   resolved "https://registry.yarnpkg.com/gauge/-/gauge-2.7.4.tgz#2c03405c7538c39d7eb37b317022e325fb018bf7"
@@ -2272,11 +2157,6 @@ ignore-walk@^3.0.1:
   dependencies:
     minimatch "^3.0.4"
 
-immediate@~3.2.3:
-  version "3.2.3"
-  resolved "https://registry.npmjs.org/immediate/-/immediate-3.2.3.tgz#d140fa8f614659bd6541233097ddaac25cdd991c"
-  integrity sha1-0UD6j2FGWb1lQSMwl92qwlzdmRw=
-
 import-lazy@^2.1.0:
   version "2.1.0"
   resolved "https://registry.yarnpkg.com/import-lazy/-/import-lazy-2.1.0.tgz#05698e3d45c88e8d7e9d92cb0584e77f096f3e43"
@@ -2303,7 +2183,7 @@ inflight@^1.0.4:
     once "^1.3.0"
     wrappy "1"
 
-inherits@2, inherits@2.0.3, inherits@^2.0.1, inherits@^2.0.3, inherits@~2.0.1, inherits@~2.0.3:
+inherits@2, inherits@2.0.3, inherits@^2.0.1, inherits@^2.0.3, inherits@~2.0.3:
   version "2.0.3"
   resolved "https://registry.yarnpkg.com/inherits/-/inherits-2.0.3.tgz#633c2c83e3da42a502f52466022480f4208261de"
   integrity sha1-Yzwsg+PaQqUC9SRmAiSA9CCCYd4=
@@ -2506,11 +2386,6 @@ is-glob@^4.0.0:
   dependencies:
     is-extglob "^2.1.1"
 
-is-hex-prefixed@1.0.0:
-  version "1.0.0"
-  resolved "https://registry.npmjs.org/is-hex-prefixed/-/is-hex-prefixed-1.0.0.tgz#7d8d37e6ad77e5d127148913c573e082d777f554"
-  integrity sha1-fY035q135dEnFIkTxXPggtd39VQ=
-
 is-installed-globally@^0.1.0:
   version "0.1.0"
   resolved "https://registry.yarnpkg.com/is-installed-globally/-/is-installed-globally-0.1.0.tgz#0dfd98f5a9111716dd535dda6492f67bf3d25a80"
@@ -2616,7 +2491,7 @@ is-symbol@^1.0.2:
   dependencies:
     has-symbols "^1.0.0"
 
-is-typedarray@^1.0.0, is-typedarray@~1.0.0:
+is-typedarray@~1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/is-typedarray/-/is-typedarray-1.0.0.tgz#e479c80858df0c1b11ddda6940f96011fcda4a9a"
   integrity sha1-5HnICFjfDBsR3dppQPlgEfzaSpo=
@@ -3172,16 +3047,6 @@ jsprim@^1.2.2:
     json-schema "0.2.3"
     verror "1.10.0"
 
-keccak@^1.0.2:
-  version "1.4.0"
-  resolved "https://registry.npmjs.org/keccak/-/keccak-1.4.0.tgz#572f8a6dbee8e7b3aa421550f9e6408ca2186f80"
-  integrity sha512-eZVaCpblK5formjPjeTBik7TAg+pqnDrMHIffSvi9Lh7PQgM1+hSzakUeZFCk9DVVG0dacZJuaz2ntwlzZUIBw==
-  dependencies:
-    bindings "^1.2.1"
-    inherits "^2.0.3"
-    nan "^2.2.1"
-    safe-buffer "^5.1.0"
-
 keccakjs@^0.2.1:
   version "0.2.3"
   resolved "https://registry.yarnpkg.com/keccakjs/-/keccakjs-0.2.3.tgz#5e4e969ce39689a3861f445d7752ee3477f9fe72"
@@ -3245,97 +3110,6 @@ left-pad@^1.3.0:
   resolved "https://registry.yarnpkg.com/left-pad/-/left-pad-1.3.0.tgz#5b8a3a7765dfe001261dde915589e782f8c94d1e"
   integrity sha512-XI5MPzVNApjAyhQzphX8BkmKsKUxD4LdyK24iZeQGinBN9yTQT3bFlCBy/aVx2HrNcqQGsdot8ghrjyrvMCoEA==
 
-level-codec@^9.0.0:
-  version "9.0.0"
-  resolved "https://registry.npmjs.org/level-codec/-/level-codec-9.0.0.tgz#2d3a0e835c4aa8339ec63de3f5a37480b74a5f87"
-  integrity sha512-OIpVvjCcZNP5SdhcNupnsI1zo5Y9Vpm+k/F1gfG5kXrtctlrwanisakweJtE0uA0OpLukRfOQae+Fg0M5Debhg==
-
-level-concat-iterator@~2.0.0:
-  version "2.0.0"
-  resolved "https://registry.npmjs.org/level-concat-iterator/-/level-concat-iterator-2.0.0.tgz#20f20242f75307540c5819b768a76881a518627b"
-  integrity sha512-gMs7JtWp479SOBjJQteQ+WMctfiQXG1SX5EuIGWTTUP37mKqs6BcYcjfZVVzAdTq0lAcSYpL2xGwmCG/hbjOcg==
-
-level-errors@^2.0.0, level-errors@~2.0.0:
-  version "2.0.0"
-  resolved "https://registry.npmjs.org/level-errors/-/level-errors-2.0.0.tgz#2de5b566b62eef92f99e19be74397fbc512563fa"
-  integrity sha512-AmY4HCp9h3OiU19uG+3YWkdELgy05OTP/r23aNHaQKWv8DO787yZgsEuGVkoph40uwN+YdUKnANlrxSsoOaaxg==
-  dependencies:
-    errno "~0.1.1"
-
-level-iterator-stream@~3.0.0:
-  version "3.0.1"
-  resolved "https://registry.npmjs.org/level-iterator-stream/-/level-iterator-stream-3.0.1.tgz#2c98a4f8820d87cdacab3132506815419077c730"
-  integrity sha512-nEIQvxEED9yRThxvOrq8Aqziy4EGzrxSZK+QzEFAVuJvQ8glfyZ96GB6BoI4sBbLfjMXm2w4vu3Tkcm9obcY0g==
-  dependencies:
-    inherits "^2.0.1"
-    readable-stream "^2.3.6"
-    xtend "^4.0.0"
-
-level-iterator-stream@~4.0.0:
-  version "4.0.0"
-  resolved "https://registry.npmjs.org/level-iterator-stream/-/level-iterator-stream-4.0.0.tgz#35ae79e714558ccf5d0c21075b2f25532bfe0270"
-  integrity sha512-CHMqFgIGXmqbdfvZcNADxRBXrl2W2EN8stxZnxEDQfEN+oNULcbX1OSK7VqJutp51Z0yJtA4Ym3JJMOuEslTrA==
-  dependencies:
-    inherits "^2.0.1"
-    readable-stream "^3.0.2"
-    xtend "^4.0.0"
-
-level-js@^4.0.0:
-  version "4.0.0"
-  resolved "https://registry.npmjs.org/level-js/-/level-js-4.0.0.tgz#1dc3e27ea29de99d549ac62a492862aa0c8186db"
-  integrity sha512-V+3MDBLYPQ+Fe6FybF69X6CgLw8lE6feL+p0aRSWaEB3x/VsNpeJ1xsbT/LoV1zrcfSDBuQBuI/Hqwn0FxBahw==
-  dependencies:
-    abstract-leveldown "~6.0.1"
-    immediate "~3.2.3"
-    inherits "^2.0.3"
-    ltgt "^2.1.2"
-    typedarray-to-buffer "~3.1.5"
-
-level-mem@^3.0.1:
-  version "3.0.1"
-  resolved "https://registry.npmjs.org/level-mem/-/level-mem-3.0.1.tgz#7ce8cf256eac40f716eb6489654726247f5a89e5"
-  integrity sha512-LbtfK9+3Ug1UmvvhR2DqLqXiPW1OJ5jEh0a3m9ZgAipiwpSxGj/qaVVy54RG5vAQN1nCuXqjvprCuKSCxcJHBg==
-  dependencies:
-    level-packager "~4.0.0"
-    memdown "~3.0.0"
-
-level-packager@~4.0.0:
-  version "4.0.1"
-  resolved "https://registry.npmjs.org/level-packager/-/level-packager-4.0.1.tgz#7e7d3016af005be0869bc5fa8de93d2a7f56ffe6"
-  integrity sha512-svCRKfYLn9/4CoFfi+d8krOtrp6RoX8+xm0Na5cgXMqSyRru0AnDYdLl+YI8u1FyS6gGZ94ILLZDE5dh2but3Q==
-  dependencies:
-    encoding-down "~5.0.0"
-    levelup "^3.0.0"
-
-level-ws@^1.0.0:
-  version "1.0.0"
-  resolved "https://registry.npmjs.org/level-ws/-/level-ws-1.0.0.tgz#19a22d2d4ac57b18cc7c6ecc4bd23d899d8f603b"
-  integrity sha512-RXEfCmkd6WWFlArh3X8ONvQPm8jNpfA0s/36M4QzLqrLEIt1iJE9WBHLZ5vZJK6haMjJPJGJCQWfjMNnRcq/9Q==
-  dependencies:
-    inherits "^2.0.3"
-    readable-stream "^2.2.8"
-    xtend "^4.0.1"
-
-levelup@^3.0.0:
-  version "3.1.1"
-  resolved "https://registry.npmjs.org/levelup/-/levelup-3.1.1.tgz#c2c0b3be2b4dc316647c53b42e2f559e232d2189"
-  integrity sha512-9N10xRkUU4dShSRRFTBdNaBxofz+PGaIZO962ckboJZiNmLuhVT6FZ6ZKAsICKfUBO76ySaYU6fJWX/jnj3Lcg==
-  dependencies:
-    deferred-leveldown "~4.0.0"
-    level-errors "~2.0.0"
-    level-iterator-stream "~3.0.0"
-    xtend "~4.0.0"
-
-levelup@^4.0.0:
-  version "4.0.0"
-  resolved "https://registry.npmjs.org/levelup/-/levelup-4.0.0.tgz#87aa76d7ff2e4da641b3e90ef274061201adf3fa"
-  integrity sha512-RcWkjtMj1DGs8ftNs4U7MEZeHFnC9QcHn/fmBlOypHXCx02zwukZROzyUwRiu9dgw9y1tCDLFMmXQHEhCChi4w==
-  dependencies:
-    deferred-leveldown "~5.0.0"
-    level-errors "~2.0.0"
-    level-iterator-stream "~4.0.0"
-    xtend "~4.0.0"
-
 leven@^2.1.0:
   version "2.1.0"
   resolved "https://registry.yarnpkg.com/leven/-/leven-2.1.0.tgz#c2e7a9f772094dee9d34202ae8acce4687875580"
@@ -3378,7 +3152,7 @@ lodash.sortby@^4.7.0:
   resolved "https://registry.yarnpkg.com/lodash.sortby/-/lodash.sortby-4.7.0.tgz#edd14c824e2cc9c1e0b0a1b42bb5210516a42438"
   integrity sha1-7dFMgk4sycHgsKG0K7UhBRakJDg=
 
-lodash@^4.13.1, lodash@^4.17.10, lodash@^4.17.11, lodash@^4.17.4:
+lodash@^4.13.1, lodash@^4.17.10, lodash@^4.17.4:
   version "4.17.11"
   resolved "https://registry.npmjs.org/lodash/-/lodash-4.17.11.tgz#b39ea6229ef607ecd89e2c8df12536891cac9b8d"
   integrity sha512-cQKh8igo5QUhZ7lg38DYWAxMvjSAKG0A8wGSVimP07SIUEK2UO+arSRKbRZWtelMtN5V0Hkwh5ryOto/SshYIg==
@@ -3403,11 +3177,6 @@ lru-cache@^4.0.1:
     pseudomap "^1.0.2"
     yallist "^2.1.2"
 
-ltgt@^2.1.2, ltgt@~2.2.0:
-  version "2.2.1"
-  resolved "https://registry.npmjs.org/ltgt/-/ltgt-2.2.1.tgz#f35ca91c493f7b73da0e07495304f17b31f87ee5"
-  integrity sha1-81ypHEk/e3PaDgdJUwTxezH4fuU=
-
 make-dir@^1.0.0:
   version "1.3.0"
   resolved "https://registry.yarnpkg.com/make-dir/-/make-dir-1.3.0.tgz#79c1033b80515bd6d24ec9933e860ca75ee27f0c"
@@ -3465,18 +3234,6 @@ mem@^1.1.0:
   dependencies:
     mimic-fn "^1.0.0"
 
-memdown@~3.0.0:
-  version "3.0.0"
-  resolved "https://registry.npmjs.org/memdown/-/memdown-3.0.0.tgz#93aca055d743b20efc37492e9e399784f2958309"
-  integrity sha512-tbV02LfZMWLcHcq4tw++NuqMO+FZX8tNJEiD2aNRm48ZZusVg5N8NART+dmBkepJVye986oixErf7jfXboMGMA==
-  dependencies:
-    abstract-leveldown "~5.0.0"
-    functional-red-black-tree "~1.0.1"
-    immediate "~3.2.3"
-    inherits "~2.0.1"
-    ltgt "~2.2.0"
-    safe-buffer "~5.1.1"
-
 merge-descriptors@1.0.1:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/merge-descriptors/-/merge-descriptors-1.0.1.tgz#b00aaa556dd8b44568150ec9d1b953f3f90cbb61"
@@ -3494,19 +3251,6 @@ merge@^1.2.0:
   resolved "https://registry.yarnpkg.com/merge/-/merge-1.2.1.tgz#38bebf80c3220a8a487b6fcfb3941bb11720c145"
   integrity sha512-VjFo4P5Whtj4vsLzsYBu5ayHhoHJ0UqNm7ibvShmbmoz7tGi0vXaoJbGdB+GmDMLUdg8DpQXEIeVDAe8MaABvQ==
 
-merkle-patricia-tree@^3.0.0:
-  version "3.0.0"
-  resolved "https://registry.npmjs.org/merkle-patricia-tree/-/merkle-patricia-tree-3.0.0.tgz#448d85415565df72febc33ca362b8b614f5a58f8"
-  integrity sha512-soRaMuNf/ILmw3KWbybaCjhx86EYeBbD8ph0edQCTed0JN/rxDt1EBN52Ajre3VyGo+91f8+/rfPIRQnnGMqmQ==
-  dependencies:
-    async "^2.6.1"
-    ethereumjs-util "^5.2.0"
-    level-mem "^3.0.1"
-    level-ws "^1.0.0"
-    readable-stream "^3.0.6"
-    rlp "^2.0.0"
-    semaphore ">=1.0.1"
-
 methods@~1.1.2:
   version "1.1.2"
   resolved "https://registry.yarnpkg.com/methods/-/methods-1.1.2.tgz#5529a4d67654134edcc5266656835b0f851afcee"
@@ -4224,11 +3968,6 @@ proxy-addr@~2.0.4:
     forwarded "~0.1.2"
     ipaddr.js "1.8.0"
 
-prr@~1.0.1:
-  version "1.0.1"
-  resolved "https://registry.npmjs.org/prr/-/prr-1.0.1.tgz#d3fc114ba06995a45ec6893f484ceb1d78f5f476"
-  integrity sha1-0/wRS6BplaRexok/SEzrHXj19HY=
-
 pseudomap@^1.0.2:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/pseudomap/-/pseudomap-1.0.2.tgz#f052a28da70e618917ef0a8ac34c1ae5a68286b3"
@@ -4339,7 +4078,7 @@ read-pkg@^1.0.0:
     normalize-package-data "^2.3.2"
     path-type "^1.0.0"
 
-readable-stream@^2.0.1, readable-stream@^2.0.2, readable-stream@^2.0.6, readable-stream@^2.2.8, readable-stream@^2.3.0, readable-stream@^2.3.5, readable-stream@^2.3.6:
+readable-stream@^2.0.1, readable-stream@^2.0.2, readable-stream@^2.0.6, readable-stream@^2.3.0, readable-stream@^2.3.5:
   version "2.3.6"
   resolved "https://registry.yarnpkg.com/readable-stream/-/readable-stream-2.3.6.tgz#b11c27d88b8ff1fbe070643cf94b0c79ae1b0aaf"
   integrity sha512-tQtKA9WIAhBF3+VLAseyMqZeBjW0AHJoxOtYqSUZNJxauErmLbVm2FW1y+J/YA9dUrAC39ITejlZWhVIwawkKw==
@@ -4352,15 +4091,6 @@ readable-stream@^2.0.1, readable-stream@^2.0.2, readable-stream@^2.0.6, readable
     string_decoder "~1.1.1"
     util-deprecate "~1.0.1"
 
-readable-stream@^3.0.2, readable-stream@^3.0.6:
-  version "3.1.1"
-  resolved "https://registry.npmjs.org/readable-stream/-/readable-stream-3.1.1.tgz#ed6bbc6c5ba58b090039ff18ce670515795aeb06"
-  integrity sha512-DkN66hPyqDhnIQ6Jcsvx9bFjhw214O4poMBcIMgPVpQvNy9a0e0Uhg5SqySyDKAmUlwt8LonTBz1ezOnM8pUdA==
-  dependencies:
-    inherits "^2.0.3"
-    string_decoder "^1.1.1"
-    util-deprecate "^1.0.1"
-
 readdirp@^2.0.0:
   version "2.2.1"
   resolved "https://registry.yarnpkg.com/readdirp/-/readdirp-2.2.1.tgz#0e87622a3325aa33e892285caf8b4e846529a525"
@@ -4542,10 +4272,10 @@ ripemd160@^2.0.0, ripemd160@^2.0.1:
     hash-base "^3.0.0"
     inherits "^2.0.1"
 
-rlp@^2.0.0:
-  version "2.2.2"
-  resolved "https://registry.npmjs.org/rlp/-/rlp-2.2.2.tgz#e6677b83cca9105371d930e01d8ffc1263139d05"
-  integrity sha512-Ng2kJEN731Sfv4ZAY2i0ytPMc0BbJKBsVNl0QZY8LxOWSwd+1xpg+fpSRfaMn0heHU447s6Kgy8qfHZR0XTyVw==
+rlp@^2.2.3:
+  version "2.2.3"
+  resolved "https://registry.yarnpkg.com/rlp/-/rlp-2.2.3.tgz#7f94aef86cec412df87d5ea1d8cb116a47d45f0e"
+  integrity sha512-l6YVrI7+d2vpW6D6rS05x2Xrmq8oW7v3pieZOJKBEdjuTF4Kz/iwk55Zyh1Zaz+KOB2kC8+2jZlp2u9L4tTzCQ==
   dependencies:
     bn.js "^4.11.1"
     safe-buffer "^5.1.1"
@@ -4555,11 +4285,6 @@ rsvp@^3.3.3:
   resolved "https://registry.yarnpkg.com/rsvp/-/rsvp-3.6.2.tgz#2e96491599a96cde1b515d5674a8f7a91452926a"
   integrity sha512-OfWGQTb9vnwRjwtA2QwpG2ICclHC3pgXZO5xt8H2EfgDquO0qVdSb5T88L4qJVAEugbS56pAuV4XZM58UX8ulw==
 
-rustbn.js@^0.2.0:
-  version "0.2.0"
-  resolved "https://registry.yarnpkg.com/rustbn.js/-/rustbn.js-0.2.0.tgz#8082cb886e707155fd1cb6f23bd591ab8d55d0ca"
-  integrity sha512-4VlvkRUuCJvr2J6Y0ImW7NvTCriMi7ErOAqWk1y69vAdoNIzCF3yPmgeNzx+RQTLEDFq5sHfscn1MwHxP9hNfA==
-
 safe-buffer@5.1.2, safe-buffer@^5.0.1, safe-buffer@^5.1.0, safe-buffer@^5.1.1, safe-buffer@^5.1.2, safe-buffer@~5.1.0, safe-buffer@~5.1.1:
   version "5.1.2"
   resolved "https://registry.yarnpkg.com/safe-buffer/-/safe-buffer-5.1.2.tgz#991ec69d296e0313747d59bdfd2b745c35f8828d"
@@ -4619,11 +4344,6 @@ seek-bzip@^1.0.5:
   dependencies:
     commander "~2.8.1"
 
-semaphore@>=1.0.1:
-  version "1.1.0"
-  resolved "https://registry.npmjs.org/semaphore/-/semaphore-1.1.0.tgz#aaad8b86b20fe8e9b32b16dc2ee682a8cd26a8aa"
-  integrity sha512-O4OZEaNtkMd/K0i6js9SL+gqy0ZCBMgUvlSqHKi4IBdjhe7wB8pwztUk1BbZ1fmrvpwFrPbHzqd2w5pTcJH6LA==
-
 semver-diff@^2.0.0:
   version "2.1.0"
   resolved "https://registry.yarnpkg.com/semver-diff/-/semver-diff-2.1.0.tgz#4bbb8437c8d37e4b0cf1a68fd726ec6d645d6d36"
@@ -4954,13 +4674,6 @@ string-width@^1.0.1:
     is-fullwidth-code-point "^2.0.0"
     strip-ansi "^4.0.0"
 
-string_decoder@^1.1.1:
-  version "1.2.0"
-  resolved "https://registry.npmjs.org/string_decoder/-/string_decoder-1.2.0.tgz#fe86e738b19544afe70469243b2a1ee9240eae8d"
-  integrity sha512-6YqyX6ZWEYguAxgZzHGL7SsCeGx3V2TtOTqZz1xSTSWnqsbWwbptafNyvf/ACquZUXV3DANr5BDIwNYe1mN42w==
-  dependencies:
-    safe-buffer "~5.1.0"
-
 string_decoder@~1.1.1:
   version "1.1.1"
   resolved "https://registry.yarnpkg.com/string_decoder/-/string_decoder-1.1.1.tgz#9cf1611ba62685d7030ae9e4ba34149c3af03fc8"
@@ -5006,13 +4719,6 @@ strip-eof@^1.0.0:
   resolved "https://registry.yarnpkg.com/strip-eof/-/strip-eof-1.0.0.tgz#bb43ff5598a6eb05d89b59fcd129c983313606bf"
   integrity sha1-u0P/VZim6wXYm1n80SnJgzE2Br8=
 
-strip-hex-prefix@1.0.0:
-  version "1.0.0"
-  resolved "https://registry.npmjs.org/strip-hex-prefix/-/strip-hex-prefix-1.0.0.tgz#0c5f155fef1151373377de9dbb588da05500e36f"
-  integrity sha1-DF8VX+8RUTczd96du1iNoFUA428=
-  dependencies:
-    is-hex-prefixed "1.0.0"
-
 strip-json-comments@~2.0.1:
   version "2.0.1"
   resolved "https://registry.yarnpkg.com/strip-json-comments/-/strip-json-comments-2.0.1.tgz#3c531942e908c2697c0ec344858c286c7ca0a60a"
@@ -5260,18 +4966,16 @@ type-is@~1.6.16:
     media-typer "0.3.0"
     mime-types "~2.1.18"
 
-typedarray-to-buffer@~3.1.5:
-  version "3.1.5"
-  resolved "https://registry.npmjs.org/typedarray-to-buffer/-/typedarray-to-buffer-3.1.5.tgz#a97ee7a9ff42691b9f783ff1bc5112fe3fca9080"
-  integrity sha512-zdu8XMNEDepKKR+XYOXAVPtWui0ly0NtohUscw+UmaHiAWT8hrV1rr//H6V+0DvJ3OQ19S979M0laLfX8rm82Q==
-  dependencies:
-    is-typedarray "^1.0.0"
-
 typescript@^3.0.3:
   version "3.3.3"
   resolved "https://registry.npmjs.org/typescript/-/typescript-3.3.3.tgz#f1657fc7daa27e1a8930758ace9ae8da31403221"
   integrity sha512-Y21Xqe54TBVp+VDSNbuDYdGw0BpoR/Q6wo/+35M8PAU0vipahnyduJWirxxdxjsAkS7hue53x2zp8gz7F05u0A==
 
+typescript@^3.2.2:
+  version "3.5.2"
+  resolved "https://registry.yarnpkg.com/typescript/-/typescript-3.5.2.tgz#a09e1dc69bc9551cadf17dba10ee42cf55e5d56c"
+  integrity sha512-7KxJovlYhTX5RaRbUdkAXN1KUZ8PwWlTzQdHV6xNqvuFOs7+WBo10TQUqT19Q/Jz2hk5v9TQDIhyLhhJY4p5AA==
+
 uglify-js@^3.1.4:
   version "3.4.9"
   resolved "https://registry.yarnpkg.com/uglify-js/-/uglify-js-3.4.9.tgz#af02f180c1207d76432e473ed24a28f4a782bae3"
@@ -5412,7 +5116,7 @@ utf8@^3.0.0:
   resolved "https://registry.yarnpkg.com/utf8/-/utf8-3.0.0.tgz#f052eed1364d696e769ef058b183df88c87f69d1"
   integrity sha512-E8VjFIQ/TyQgp+TZfS6l8yp/xWppSAHzidGiRrqe4bK4XP9pTRyKFgGJpO3SN7zdX4DeomTrwaseCHovfpFcqQ==
 
-util-deprecate@^1.0.1, util-deprecate@~1.0.1:
+util-deprecate@~1.0.1:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/util-deprecate/-/util-deprecate-1.0.2.tgz#450d4dc9fa70de732762fbd2d4a28981419a0ccf"
   integrity sha1-RQ1Nyfpw3nMnYvvS1KKJgUGaDM8=
@@ -5479,32 +5183,35 @@ watch@~0.18.0:
     exec-sh "^0.2.0"
     minimist "^1.2.0"
 
-web3x@^3.0.11:
-  version "3.0.11"
-  resolved "https://registry.yarnpkg.com/web3x/-/web3x-3.0.11.tgz#93ca7b594f1a79580680035ea8066a263e3bbd6b"
-  integrity sha512-gzWAXrbeHtsLxU/aInhxyU8b9y6OKuP5+bOrchwFzjM00q60FIOBiebweon5s1g9WATt1045AlBhDf2naDGkNA==
+web3x-codegen@^4.0.0:
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/web3x-codegen/-/web3x-codegen-4.0.0.tgz#670e6c128df9802294d16587c8f0af0a4c488b46"
+  integrity sha512-Gn/GAahH/xs/oaHRIhCfKyKyP6Jd0zPJD+zDt13SOh1jodmUZzJa97flfXoGbCAuFW3FKYW90AUKhdVi5ULkxw==
+  dependencies:
+    fs-extra "^7.0.1"
+    got "^9.3.0"
+    typescript "^3.2.2"
+    web3x "^4.0.0"
+
+web3x@^4.0.0:
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/web3x/-/web3x-4.0.0.tgz#b597870a69fbe0be516408223e787e3004ab9881"
+  integrity sha512-bBgOyEL4B49FxtNT0IVpTDJKQ8Az4AgggDx4rbj150VylJ1xVscq7yblh2ZjOe4+8GtuD7vxeuYuY0RIb0/I0Q==
   dependencies:
     "@types/bn.js" "^4.11.2"
-    "@types/levelup" "^3.1.0"
     "@types/node" "^10.12.18"
     "@types/ws" "^6.0.1"
-    bigint-buffer "^1.1.2"
     bip39 "^2.5.0"
     bn.js "^4.11.8"
     browserify-aes "^1.2.0"
     elliptic "^6.4.0"
-    fs-extra "^7.0.1"
-    got "^9.3.0"
     hdkey "^1.1.0"
     idna-uts46-hx "^2.3.1"
     isomorphic-ws "^4.0.1"
-    level-js "^4.0.0"
-    levelup "^4.0.0"
-    merkle-patricia-tree "^3.0.0"
     node-http-xhr "^1.3.4"
     pbkdf2 "^3.0.17"
     randombytes "^2.0.6"
-    rustbn.js "^0.2.0"
+    rlp "^2.2.3"
     swarm-js "^0.1.39"
     tslib "^1.9.3"
     utf8 "^3.0.0"
@@ -5666,7 +5373,7 @@ xml-name-validator@^3.0.0:
   resolved "https://registry.yarnpkg.com/xml-name-validator/-/xml-name-validator-3.0.0.tgz#6ae73e06de4d8c6e47f9fb181f78d648ad457c6a"
   integrity sha512-A5CUptxDsvxKJEU3yO6DuWBSJz/qizqzJKOMIfUJHETbBw/sFaDxgd6fxm1ewUaM0jZ444Fc5vC5ROYurg/4Pw==
 
-xtend@^4.0.0, xtend@^4.0.1, xtend@~4.0.0:
+xtend@^4.0.0:
   version "4.0.1"
   resolved "https://registry.yarnpkg.com/xtend/-/xtend-4.0.1.tgz#a5c6d532be656e23db820efb943a1f04998d63af"
   integrity sha1-pcbVMr5lbiPbgg77lDofBJmNY68=
diff --git a/web3x-webpack-example/package.json b/web3x-webpack-example/package.json
index 65fb10e..51bf4fb 100644
--- a/web3x-webpack-example/package.json
+++ b/web3x-webpack-example/package.json
@@ -47,6 +47,7 @@
     "tslint": "^5.11.0",
     "tslint-config-prettier": "^1.15.0",
     "typescript": "^2.9.1",
+    "web3x-codegen": "^4.0.0",
     "web3x-es": "^4.0.0",
     "webpack": "^4.16.0",
     "webpack-cli": "^3.0.8",
diff --git a/web3x-webpack-example/src/contracts/DaiContract.ts b/web3x-webpack-example/src/contracts/DaiContract.ts
index 41f6172..2d6e2c1 100644
--- a/web3x-webpack-example/src/contracts/DaiContract.ts
+++ b/web3x-webpack-example/src/contracts/DaiContract.ts
@@ -1,10 +1,3 @@
-/*
-  Copyright (c) 2019 xf00f
-
-  This file is part of web3x and is released under the MIT License.
-  https://opensource.org/licenses/MIT
-*/
-
 import BN from "bn.js";
 import { Address } from "web3x-es/address";
 import { EventLog, TransactionReceipt } from "web3x-es/formatters";
diff --git a/web3x-webpack-example/src/contracts/DaiContractAbi.ts b/web3x-webpack-example/src/contracts/DaiContractAbi.ts
index 8e06a73..ab0ce61 100644
--- a/web3x-webpack-example/src/contracts/DaiContractAbi.ts
+++ b/web3x-webpack-example/src/contracts/DaiContractAbi.ts
@@ -1,10 +1,3 @@
-/*
-  Copyright (c) 2019 xf00f
-
-  This file is part of web3x and is released under the MIT License.
-  https://opensource.org/licenses/MIT
-*/
-
 import { ContractAbi} from 'web3x-es/contract';
 export default new ContractAbi([
   {
diff --git a/web3x-webpack-example/yarn.lock b/web3x-webpack-example/yarn.lock
index af11088..c30a914 100644
--- a/web3x-webpack-example/yarn.lock
+++ b/web3x-webpack-example/yarn.lock
@@ -595,11 +595,6 @@
   dependencies:
     defer-to-connect "^1.0.1"
 
-"@types/abstract-leveldown@*":
-  version "5.0.1"
-  resolved "https://registry.yarnpkg.com/@types/abstract-leveldown/-/abstract-leveldown-5.0.1.tgz#3c7750d0186b954c7f2d2f6acc8c3c7ba0c3412e"
-  integrity sha512-wYxU3kp5zItbxKmeRYCEplS2MW7DzyBnxPGj+GJVHZEUZiK/nn5Ei1sUFgURDh+X051+zsGe28iud3oHjrYWQQ==
-
 "@types/accepts@*":
   version "1.3.5"
   resolved "https://registry.npmjs.org/@types/accepts/-/accepts-1.3.5.tgz#c34bec115cfc746e04fe5a059df4ce7e7b391575"
@@ -710,15 +705,6 @@
     "@types/koa-compose" "*"
     "@types/node" "*"
 
-"@types/levelup@^3.1.0":
-  version "3.1.0"
-  resolved "https://registry.yarnpkg.com/@types/levelup/-/levelup-3.1.0.tgz#e04f6a8eaf707f88d7c6e043a9067dda431f4538"
-  integrity sha512-Y2SC5PskYsE8+dELuWLCMG+UcUrkhhIz5wV55yX73AAVqr3kDXLYlj6k/vuchXUt1L1b/P1Frt4Dcc3WmWcbLA==
-  dependencies:
-    "@types/abstract-leveldown" "*"
-    "@types/events" "*"
-    "@types/node" "*"
-
 "@types/mime@*":
   version "2.0.0"
   resolved "https://registry.npmjs.org/@types/mime/-/mime-2.0.0.tgz#5a7306e367c539b9f6543499de8dd519fac37a8b"
@@ -923,21 +909,6 @@ abbrev@1:
   resolved "https://registry.npmjs.org/abbrev/-/abbrev-1.1.1.tgz#f8f2c887ad10bf67f634f005b6987fed3179aac8"
   integrity sha512-nne9/IiQ/hzIhY6pdDnbBtz7DjPTKrY00P/zvPSm5pOFkl6xuGrGnXn/VtTNNfNtAfZ9/1RtehkszU9qcTii0Q==
 
-abstract-leveldown@^5.0.0, abstract-leveldown@~5.0.0:
-  version "5.0.0"
-  resolved "https://registry.yarnpkg.com/abstract-leveldown/-/abstract-leveldown-5.0.0.tgz#f7128e1f86ccabf7d2893077ce5d06d798e386c6"
-  integrity sha512-5mU5P1gXtsMIXg65/rsYGsi93+MlogXZ9FA8JnwKurHQg64bfXwGYVdVdijNTVNOlAsuIiOwHdvFFD5JqCJQ7A==
-  dependencies:
-    xtend "~4.0.0"
-
-abstract-leveldown@~6.0.0, abstract-leveldown@~6.0.1:
-  version "6.0.3"
-  resolved "https://registry.yarnpkg.com/abstract-leveldown/-/abstract-leveldown-6.0.3.tgz#b4b6159343c74b0c5197b2817854782d8f748c4a"
-  integrity sha512-jzewKKpZbaYUa6HTThnrl+GrJhzjEAeuc7hTVpZdzg7kupXZFoqQDFwyOwLNbmJKJlmzw8yiipMPkDiuKkT06Q==
-  dependencies:
-    level-concat-iterator "~2.0.0"
-    xtend "~4.0.0"
-
 accepts@^1.3.5, accepts@~1.3.4, accepts@~1.3.5:
   version "1.3.5"
   resolved "https://registry.npmjs.org/accepts/-/accepts-1.3.5.tgz#eb777df6011723a3b14e8a72c0805c8e86746bd2"
@@ -1207,13 +1178,6 @@ async@^2.1.4, async@^2.5.0:
   dependencies:
     lodash "^4.17.10"
 
-async@^2.6.1:
-  version "2.6.2"
-  resolved "https://registry.yarnpkg.com/async/-/async-2.6.2.tgz#18330ea7e6e313887f5d2f2a904bac6fe4dd5381"
-  integrity sha512-H1qVYh1MYhEEFLsP97cVKqCGo7KfCyTt6uEWqsTBr9SO84oK9Uwbyd/yCW+6rKJLHksBNUVWZDAjfS+Ccx0Bbg==
-  dependencies:
-    lodash "^4.17.11"
-
 asynckit@^0.4.0:
   version "0.4.0"
   resolved "https://registry.npmjs.org/asynckit/-/asynckit-0.4.0.tgz#c79ed97f7f34cb8f2ba1bc9790bcc366474b4b79"
@@ -1399,13 +1363,6 @@ big.js@^3.1.3:
   resolved "https://registry.npmjs.org/big.js/-/big.js-3.2.0.tgz#a5fc298b81b9e0dca2e458824784b65c52ba588e"
   integrity sha512-+hN/Zh2D08Mx65pZ/4g5bsmNiZUuChDiQfTUQ7qJr4/kuopCr88xZsAXv6mBoZEsUI4OuGHlX59qE94K2mMW8Q==
 
-bigint-buffer@^1.1.2:
-  version "1.1.2"
-  resolved "https://registry.yarnpkg.com/bigint-buffer/-/bigint-buffer-1.1.2.tgz#b7edfaf3a88d0767aed7edc671d6bae4b1021575"
-  integrity sha512-gof9NgbodUgCXD2aUHfUKk5KUDk6/zPlwE+YYpRM2t7zS0K/6WipJFWfziIY+EavxFDuGUnuuQQzzvNcckPKNA==
-  dependencies:
-    bindings "^1.3.0"
-
 binary-extensions@^1.0.0:
   version "1.12.0"
   resolved "https://registry.npmjs.org/binary-extensions/-/binary-extensions-1.12.0.tgz#c2d780f53d45bba8317a8902d4ceeaf3a6385b14"
@@ -1416,13 +1373,6 @@ bindings@^1.2.1:
   resolved "https://registry.npmjs.org/bindings/-/bindings-1.3.1.tgz#21fc7c6d67c18516ec5aaa2815b145ff77b26ea5"
   integrity sha512-i47mqjF9UbjxJhxGf+pZ6kSxrnI3wBLlnGI2ArWJ4r0VrvDS7ZYXkprq/pLaBWYq4GM0r4zdHY+NNRqEMU7uew==
 
-bindings@^1.3.0:
-  version "1.5.0"
-  resolved "https://registry.yarnpkg.com/bindings/-/bindings-1.5.0.tgz#10353c9e945334bc0511a6d90b38fbc7c9c504df"
-  integrity sha512-p2q/t/mhvuOj/UeLlV6566GD/guowlr0hHxClI0W9m7MWYkL1F0hLo+0Aexs9HSPCtR1SXQ0TD3MMKrXZajbiQ==
-  dependencies:
-    file-uri-to-path "1.0.0"
-
 bip39@^2.5.0:
   version "2.5.0"
   resolved "https://registry.npmjs.org/bip39/-/bip39-2.5.0.tgz#51cbd5179460504a63ea3c000db3f787ca051235"
@@ -1459,7 +1409,7 @@ bluebird@^3.5.1:
   resolved "https://registry.npmjs.org/bluebird/-/bluebird-3.5.2.tgz#1be0908e054a751754549c270489c1505d4ab15a"
   integrity sha512-dhHTWMI7kMx5whMQntl7Vr9C6BvV10lFXDAasnqnrMYhXVCzzk6IO9Fo2L75jXHT07WrOngL1WDXOp+yYS91Yg==
 
-bn.js@^4.0.0, bn.js@^4.1.0, bn.js@^4.1.1, bn.js@^4.11.0, bn.js@^4.11.1, bn.js@^4.11.3, bn.js@^4.11.6, bn.js@^4.11.8, bn.js@^4.4.0:
+bn.js@^4.0.0, bn.js@^4.1.0, bn.js@^4.1.1, bn.js@^4.11.1, bn.js@^4.11.3, bn.js@^4.11.6, bn.js@^4.11.8, bn.js@^4.4.0:
   version "4.11.8"
   resolved "https://registry.npmjs.org/bn.js/-/bn.js-4.11.8.tgz#2cde09eb5ee341f484746bb0309b3253b1b1442f"
   integrity sha512-ItfYfPLkWHUjckQCk8xC+LwxgK8NYcXywGigJgSwOP8Y2iyWT4f2vsZnoOXTTbo+o5yXmIUJ4gn5538SO5S3gA==
@@ -2388,22 +2338,6 @@ defer-to-connect@^1.0.1:
   resolved "https://registry.npmjs.org/defer-to-connect/-/defer-to-connect-1.0.1.tgz#41ec1dd670dc4c6dcbe7e54c9e44d784d025fe63"
   integrity sha512-2e0FJesseUqQj671gvZWfUyxpnFx/5n4xleamlpCD3U6Fm5dh5qzmmLNxNhtmHF06+SYVHH8QU6FACffYTnj0Q==
 
-deferred-leveldown@~4.0.0:
-  version "4.0.2"
-  resolved "https://registry.yarnpkg.com/deferred-leveldown/-/deferred-leveldown-4.0.2.tgz#0b0570087827bf480a23494b398f04c128c19a20"
-  integrity sha512-5fMC8ek8alH16QiV0lTCis610D1Zt1+LA4MS4d63JgS32lrCjTFDUFz2ao09/j2I4Bqb5jL4FZYwu7Jz0XO1ww==
-  dependencies:
-    abstract-leveldown "~5.0.0"
-    inherits "^2.0.3"
-
-deferred-leveldown@~5.0.0:
-  version "5.0.1"
-  resolved "https://registry.yarnpkg.com/deferred-leveldown/-/deferred-leveldown-5.0.1.tgz#1642eb18b535dfb2b6ac4d39fb10a9cbcfd13b09"
-  integrity sha512-BXohsvTedWOLkj2n/TY+yqVlrCWa2Zs8LSxh3uCAgFOru7/pjxKyZAexGa1j83BaKloER4PqUyQ9rGPJLt9bqA==
-  dependencies:
-    abstract-leveldown "~6.0.0"
-    inherits "^2.0.3"
-
 define-properties@^1.1.2:
   version "1.1.3"
   resolved "https://registry.npmjs.org/define-properties/-/define-properties-1.1.3.tgz#cf88da6cbee26fe6db7094f61d870cbd84cee9f1"
@@ -2663,17 +2597,6 @@ encodeurl@~1.0.2:
   resolved "https://registry.npmjs.org/encodeurl/-/encodeurl-1.0.2.tgz#ad3ff4c86ec2d029322f5a02c3a9a606c95b3f59"
   integrity sha1-rT/0yG7C0CkyL1oCw6mmBslbP1k=
 
-encoding-down@~5.0.0:
-  version "5.0.4"
-  resolved "https://registry.yarnpkg.com/encoding-down/-/encoding-down-5.0.4.tgz#1e477da8e9e9d0f7c8293d320044f8b2cd8e9614"
-  integrity sha512-8CIZLDcSKxgzT+zX8ZVfgNbu8Md2wq/iqa1Y7zyVR18QBEAc0Nmzuvj/N5ykSKpfGzjM8qxbaFntLPwnVoUhZw==
-  dependencies:
-    abstract-leveldown "^5.0.0"
-    inherits "^2.0.3"
-    level-codec "^9.0.0"
-    level-errors "^2.0.0"
-    xtend "^4.0.1"
-
 end-of-stream@^1.0.0, end-of-stream@^1.1.0:
   version "1.4.1"
   resolved "https://registry.npmjs.org/end-of-stream/-/end-of-stream-1.4.1.tgz#ed29634d19baba463b6ce6b80a37213eab71ec43"
@@ -2695,7 +2618,7 @@ entities@~1.1.1:
   resolved "https://registry.npmjs.org/entities/-/entities-1.1.1.tgz#6e5c2d0a5621b5dadaecef80b90edfb5cd7772f0"
   integrity sha1-blwtClYhtdra7O+AuQ7ftc13cvA=
 
-errno@^0.1.3, errno@~0.1.1, errno@~0.1.7:
+errno@^0.1.3, errno@~0.1.7:
   version "0.1.7"
   resolved "https://registry.npmjs.org/errno/-/errno-0.1.7.tgz#4684d71779ad39af177e3f007996f7c67c852618"
   integrity sha512-MfrRBDWzIWifgq6tJj60gkAwtLNb6sQPlcFrSOflcP1aFmmruKQ2wRnze/8V6kgyz7H3FF8Npzv78mZ7XLLflg==
@@ -2809,27 +2732,6 @@ eth-lib@^0.1.26:
     ws "^3.0.0"
     xhr-request-promise "^0.1.2"
 
-ethereumjs-util@^5.2.0:
-  version "5.2.0"
-  resolved "https://registry.yarnpkg.com/ethereumjs-util/-/ethereumjs-util-5.2.0.tgz#3e0c0d1741471acf1036052d048623dee54ad642"
-  integrity sha512-CJAKdI0wgMbQFLlLRtZKGcy/L6pzVRgelIZqRqNbuVFM3K9VEnyfbcvz0ncWMRNCe4kaHWjwRYQcYMucmwsnWA==
-  dependencies:
-    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"
-
-ethjs-util@^0.1.3:
-  version "0.1.6"
-  resolved "https://registry.yarnpkg.com/ethjs-util/-/ethjs-util-0.1.6.tgz#f308b62f185f9fe6237132fb2a9818866a5cd536"
-  integrity sha512-CUnVOQq7gSpDHZVVrQW8ExxUETWrnrvXYvYz55wOU8Uj4VCgw56XC2B/fVqQN+f7gmrnRHSLVnFAwsCuNwji8w==
-  dependencies:
-    is-hex-prefixed "1.0.0"
-    strip-hex-prefix "1.0.0"
-
 eventemitter3@^3.0.0:
   version "3.1.0"
   resolved "https://registry.npmjs.org/eventemitter3/-/eventemitter3-3.1.0.tgz#090b4d6cdbd645ed10bf750d4b5407942d7ba163"
@@ -3113,11 +3015,6 @@ file-type@^6.1.0:
   resolved "https://registry.npmjs.org/file-type/-/file-type-6.2.0.tgz#e50cd75d356ffed4e306dc4f5bcf52a79903a919"
   integrity sha512-YPcTBDV+2Tm0VqjybVd32MHdlEGAtuxS3VAYsumFokDSMG+ROT5wawGlnHDoz7bfMcMDt9hxuXvXwoKUx2fkOg==
 
-file-uri-to-path@1.0.0:
-  version "1.0.0"
-  resolved "https://registry.yarnpkg.com/file-uri-to-path/-/file-uri-to-path-1.0.0.tgz#553a7b8446ff6f684359c445f1e37a05dacc33dd"
-  integrity sha512-0Zt+s3L7Vf1biwWZ29aARiVYLx7iMGnEUl9x33fbB/j3jR81u/O2LbqK+Bm1CDSNDKVtJ/YjwY7TUd5SkeLQLw==
-
 filename-regex@^2.0.0:
   version "2.0.1"
   resolved "https://registry.npmjs.org/filename-regex/-/filename-regex-2.0.1.tgz#c1c4b9bee3e09725ddb106b75c1e301fe2f18b26"
@@ -3327,11 +3224,6 @@ function-bind@^1.1.1:
   resolved "https://registry.npmjs.org/function-bind/-/function-bind-1.1.1.tgz#a56899d3ea3c9bab874bb9773b7c5ede92f4895d"
   integrity sha512-yIovAzMX49sF8Yl58fSCWJ5svSLuaibPxXQJFLmBObTuCr0Mf1KiPopGM9NiFjiYBCbfaa2Fh6breQ6ANVTI0A==
 
-functional-red-black-tree@~1.0.1:
-  version "1.0.1"
-  resolved "https://registry.yarnpkg.com/functional-red-black-tree/-/functional-red-black-tree-1.0.1.tgz#1b0ab3bd553b2a0d6399d29c0e3ea0b252078327"
-  integrity sha1-GwqzvVU7Kg1jmdKcDj6gslIHgyc=
-
 gauge@~2.7.3:
   version "2.7.4"
   resolved "https://registry.npmjs.org/gauge/-/gauge-2.7.4.tgz#2c03405c7538c39d7eb37b317022e325fb018bf7"
@@ -3847,11 +3739,6 @@ ignore-walk@^3.0.1:
   dependencies:
     minimatch "^3.0.4"
 
-immediate@~3.2.3:
-  version "3.2.3"
-  resolved "https://registry.yarnpkg.com/immediate/-/immediate-3.2.3.tgz#d140fa8f614659bd6541233097ddaac25cdd991c"
-  integrity sha1-0UD6j2FGWb1lQSMwl92qwlzdmRw=
-
 import-local@^1.0.0:
   version "1.0.0"
   resolved "https://registry.npmjs.org/import-local/-/import-local-1.0.0.tgz#5e4ffdc03f4fe6c009c6729beb29631c2f8227bc"
@@ -4127,11 +4014,6 @@ is-glob@^4.0.0:
   dependencies:
     is-extglob "^2.1.1"
 
-is-hex-prefixed@1.0.0:
-  version "1.0.0"
-  resolved "https://registry.yarnpkg.com/is-hex-prefixed/-/is-hex-prefixed-1.0.0.tgz#7d8d37e6ad77e5d127148913c573e082d777f554"
-  integrity sha1-fY035q135dEnFIkTxXPggtd39VQ=
-
 is-natural-number@^4.0.1:
   version "4.0.1"
   resolved "https://registry.npmjs.org/is-natural-number/-/is-natural-number-4.0.1.tgz#ab9d76e1db4ced51e35de0c72ebecf09f734cde8"
@@ -4226,7 +4108,7 @@ is-symbol@^1.0.2:
   dependencies:
     has-symbols "^1.0.0"
 
-is-typedarray@^1.0.0, is-typedarray@~1.0.0:
+is-typedarray@~1.0.0:
   version "1.0.0"
   resolved "https://registry.npmjs.org/is-typedarray/-/is-typedarray-1.0.0.tgz#e479c80858df0c1b11ddda6940f96011fcda4a9a"
   integrity sha1-5HnICFjfDBsR3dppQPlgEfzaSpo=
@@ -4817,16 +4699,6 @@ jsprim@^1.2.2:
     json-schema "0.2.3"
     verror "1.10.0"
 
-keccak@^1.0.2:
-  version "1.4.0"
-  resolved "https://registry.yarnpkg.com/keccak/-/keccak-1.4.0.tgz#572f8a6dbee8e7b3aa421550f9e6408ca2186f80"
-  integrity sha512-eZVaCpblK5formjPjeTBik7TAg+pqnDrMHIffSvi9Lh7PQgM1+hSzakUeZFCk9DVVG0dacZJuaz2ntwlzZUIBw==
-  dependencies:
-    bindings "^1.2.1"
-    inherits "^2.0.3"
-    nan "^2.2.1"
-    safe-buffer "^5.1.0"
-
 keccakjs@^0.2.1:
   version "0.2.3"
   resolved "https://registry.npmjs.org/keccakjs/-/keccakjs-0.2.3.tgz#5e4e969ce39689a3861f445d7752ee3477f9fe72"
@@ -4973,97 +4845,6 @@ left-pad@^1.3.0:
   resolved "https://registry.npmjs.org/left-pad/-/left-pad-1.3.0.tgz#5b8a3a7765dfe001261dde915589e782f8c94d1e"
   integrity sha512-XI5MPzVNApjAyhQzphX8BkmKsKUxD4LdyK24iZeQGinBN9yTQT3bFlCBy/aVx2HrNcqQGsdot8ghrjyrvMCoEA==
 
-level-codec@^9.0.0:
-  version "9.0.1"
-  resolved "https://registry.yarnpkg.com/level-codec/-/level-codec-9.0.1.tgz#042f4aa85e56d4328ace368c950811ba802b7247"
-  integrity sha512-ajFP0kJ+nyq4i6kptSM+mAvJKLOg1X5FiFPtLG9M5gCEZyBmgDi3FkDrvlMkEzrUn1cWxtvVmrvoS4ASyO/q+Q==
-
-level-concat-iterator@~2.0.0:
-  version "2.0.1"
-  resolved "https://registry.yarnpkg.com/level-concat-iterator/-/level-concat-iterator-2.0.1.tgz#1d1009cf108340252cb38c51f9727311193e6263"
-  integrity sha512-OTKKOqeav2QWcERMJR7IS9CUo1sHnke2C0gkSmcR7QuEtFNLLzHQAvnMw8ykvEcv0Qtkg0p7FOwP1v9e5Smdcw==
-
-level-errors@^2.0.0, level-errors@~2.0.0:
-  version "2.0.1"
-  resolved "https://registry.yarnpkg.com/level-errors/-/level-errors-2.0.1.tgz#2132a677bf4e679ce029f517c2f17432800c05c8"
-  integrity sha512-UVprBJXite4gPS+3VznfgDSU8PTRuVX0NXwoWW50KLxd2yw4Y1t2JUR5In1itQnudZqRMT9DlAM3Q//9NCjCFw==
-  dependencies:
-    errno "~0.1.1"
-
-level-iterator-stream@~3.0.0:
-  version "3.0.1"
-  resolved "https://registry.yarnpkg.com/level-iterator-stream/-/level-iterator-stream-3.0.1.tgz#2c98a4f8820d87cdacab3132506815419077c730"
-  integrity sha512-nEIQvxEED9yRThxvOrq8Aqziy4EGzrxSZK+QzEFAVuJvQ8glfyZ96GB6BoI4sBbLfjMXm2w4vu3Tkcm9obcY0g==
-  dependencies:
-    inherits "^2.0.1"
-    readable-stream "^2.3.6"
-    xtend "^4.0.0"
-
-level-iterator-stream@~4.0.0:
-  version "4.0.1"
-  resolved "https://registry.yarnpkg.com/level-iterator-stream/-/level-iterator-stream-4.0.1.tgz#65c467070c0788fe0d08a0c1ed600c3b9e82bc8d"
-  integrity sha512-pSZWqXK6/yHQkZKCHrR59nKpU5iqorKM22C/BOHTb/cwNQ2EOZG+bovmFFGcOgaBoF3KxqJEI27YwewhJQTzsw==
-  dependencies:
-    inherits "^2.0.1"
-    readable-stream "^3.0.2"
-    xtend "^4.0.0"
-
-level-js@^4.0.0:
-  version "4.0.1"
-  resolved "https://registry.yarnpkg.com/level-js/-/level-js-4.0.1.tgz#3bad57d8bb46ebba7b13bc7442b56f4b45c8a2e0"
-  integrity sha512-m5JRIyHZn5VnCCFeRegJkn5bQd3MJK5qZX12zg3Oivc8+BUIS2yFS6ANMMeHX2ieGxucNvEn6/ZnyjmZQLLUWw==
-  dependencies:
-    abstract-leveldown "~6.0.1"
-    immediate "~3.2.3"
-    inherits "^2.0.3"
-    ltgt "^2.1.2"
-    typedarray-to-buffer "~3.1.5"
-
-level-mem@^3.0.1:
-  version "3.0.1"
-  resolved "https://registry.yarnpkg.com/level-mem/-/level-mem-3.0.1.tgz#7ce8cf256eac40f716eb6489654726247f5a89e5"
-  integrity sha512-LbtfK9+3Ug1UmvvhR2DqLqXiPW1OJ5jEh0a3m9ZgAipiwpSxGj/qaVVy54RG5vAQN1nCuXqjvprCuKSCxcJHBg==
-  dependencies:
-    level-packager "~4.0.0"
-    memdown "~3.0.0"
-
-level-packager@~4.0.0:
-  version "4.0.1"
-  resolved "https://registry.yarnpkg.com/level-packager/-/level-packager-4.0.1.tgz#7e7d3016af005be0869bc5fa8de93d2a7f56ffe6"
-  integrity sha512-svCRKfYLn9/4CoFfi+d8krOtrp6RoX8+xm0Na5cgXMqSyRru0AnDYdLl+YI8u1FyS6gGZ94ILLZDE5dh2but3Q==
-  dependencies:
-    encoding-down "~5.0.0"
-    levelup "^3.0.0"
-
-level-ws@^1.0.0:
-  version "1.0.0"
-  resolved "https://registry.yarnpkg.com/level-ws/-/level-ws-1.0.0.tgz#19a22d2d4ac57b18cc7c6ecc4bd23d899d8f603b"
-  integrity sha512-RXEfCmkd6WWFlArh3X8ONvQPm8jNpfA0s/36M4QzLqrLEIt1iJE9WBHLZ5vZJK6haMjJPJGJCQWfjMNnRcq/9Q==
-  dependencies:
-    inherits "^2.0.3"
-    readable-stream "^2.2.8"
-    xtend "^4.0.1"
-
-levelup@^3.0.0:
-  version "3.1.1"
-  resolved "https://registry.yarnpkg.com/levelup/-/levelup-3.1.1.tgz#c2c0b3be2b4dc316647c53b42e2f559e232d2189"
-  integrity sha512-9N10xRkUU4dShSRRFTBdNaBxofz+PGaIZO962ckboJZiNmLuhVT6FZ6ZKAsICKfUBO76ySaYU6fJWX/jnj3Lcg==
-  dependencies:
-    deferred-leveldown "~4.0.0"
-    level-errors "~2.0.0"
-    level-iterator-stream "~3.0.0"
-    xtend "~4.0.0"
-
-levelup@^4.0.0:
-  version "4.0.1"
-  resolved "https://registry.yarnpkg.com/levelup/-/levelup-4.0.1.tgz#26321eb33ec1ddac1f29b1ac82f8b693e2cbf182"
-  integrity sha512-l7KXOkINXHgNqmz0v9bxvRnMCUG4gmShFrzFSZXXhcqFnfvKAW8NerVsTICpZtVhGOMAmhY6JsVoVh/tUPBmdg==
-  dependencies:
-    deferred-leveldown "~5.0.0"
-    level-errors "~2.0.0"
-    level-iterator-stream "~4.0.0"
-    xtend "~4.0.0"
-
 leven@^2.1.0:
   version "2.1.0"
   resolved "https://registry.npmjs.org/leven/-/leven-2.1.0.tgz#c2e7a9f772094dee9d34202ae8acce4687875580"
@@ -5138,7 +4919,7 @@ lodash.sortby@^4.7.0:
   resolved "https://registry.npmjs.org/lodash.sortby/-/lodash.sortby-4.7.0.tgz#edd14c824e2cc9c1e0b0a1b42bb5210516a42438"
   integrity sha1-7dFMgk4sycHgsKG0K7UhBRakJDg=
 
-lodash@^4.13.1, lodash@^4.17.10, lodash@^4.17.11, lodash@^4.17.3, lodash@^4.17.4, lodash@^4.17.5:
+lodash@^4.13.1, lodash@^4.17.10, lodash@^4.17.3, lodash@^4.17.4, lodash@^4.17.5:
   version "4.17.11"
   resolved "https://registry.npmjs.org/lodash/-/lodash-4.17.11.tgz#b39ea6229ef607ecd89e2c8df12536891cac9b8d"
   integrity sha512-cQKh8igo5QUhZ7lg38DYWAxMvjSAKG0A8wGSVimP07SIUEK2UO+arSRKbRZWtelMtN5V0Hkwh5ryOto/SshYIg==
@@ -5173,11 +4954,6 @@ lru-cache@^4.0.1, lru-cache@^4.1.1:
     pseudomap "^1.0.2"
     yallist "^2.1.2"
 
-ltgt@^2.1.2, ltgt@~2.2.0:
-  version "2.2.1"
-  resolved "https://registry.yarnpkg.com/ltgt/-/ltgt-2.2.1.tgz#f35ca91c493f7b73da0e07495304f17b31f87ee5"
-  integrity sha1-81ypHEk/e3PaDgdJUwTxezH4fuU=
-
 make-dir@^1.0.0:
   version "1.3.0"
   resolved "https://registry.npmjs.org/make-dir/-/make-dir-1.3.0.tgz#79c1033b80515bd6d24ec9933e860ca75ee27f0c"
@@ -5251,18 +5027,6 @@ mem@^4.0.0:
     mimic-fn "^1.0.0"
     p-is-promise "^1.1.0"
 
-memdown@~3.0.0:
-  version "3.0.0"
-  resolved "https://registry.yarnpkg.com/memdown/-/memdown-3.0.0.tgz#93aca055d743b20efc37492e9e399784f2958309"
-  integrity sha512-tbV02LfZMWLcHcq4tw++NuqMO+FZX8tNJEiD2aNRm48ZZusVg5N8NART+dmBkepJVye986oixErf7jfXboMGMA==
-  dependencies:
-    abstract-leveldown "~5.0.0"
-    functional-red-black-tree "~1.0.1"
-    immediate "~3.2.3"
-    inherits "~2.0.1"
-    ltgt "~2.2.0"
-    safe-buffer "~5.1.1"
-
 memory-fs@^0.4.0, memory-fs@~0.4.1:
   version "0.4.1"
   resolved "https://registry.npmjs.org/memory-fs/-/memory-fs-0.4.1.tgz#3a9a20b8462523e447cfbc7e8bb80ed667bfc552"
@@ -5288,19 +5052,6 @@ merge@^1.2.0:
   resolved "https://registry.npmjs.org/merge/-/merge-1.2.0.tgz#7531e39d4949c281a66b8c5a6e0265e8b05894da"
   integrity sha1-dTHjnUlJwoGma4xabgJl6LBYlNo=
 
-merkle-patricia-tree@^3.0.0:
-  version "3.0.0"
-  resolved "https://registry.yarnpkg.com/merkle-patricia-tree/-/merkle-patricia-tree-3.0.0.tgz#448d85415565df72febc33ca362b8b614f5a58f8"
-  integrity sha512-soRaMuNf/ILmw3KWbybaCjhx86EYeBbD8ph0edQCTed0JN/rxDt1EBN52Ajre3VyGo+91f8+/rfPIRQnnGMqmQ==
-  dependencies:
-    async "^2.6.1"
-    ethereumjs-util "^5.2.0"
-    level-mem "^3.0.1"
-    level-ws "^1.0.0"
-    readable-stream "^3.0.6"
-    rlp "^2.0.0"
-    semaphore ">=1.0.1"
-
 methods@~1.1.2:
   version "1.1.2"
   resolved "https://registry.npmjs.org/methods/-/methods-1.1.2.tgz#5529a4d67654134edcc5266656835b0f851afcee"
@@ -6480,7 +6231,7 @@ read-pkg@^1.0.0:
     normalize-package-data "^2.3.2"
     path-type "^1.0.0"
 
-"readable-stream@1 || 2", readable-stream@^2.0.0, readable-stream@^2.0.1, readable-stream@^2.0.2, readable-stream@^2.0.4, readable-stream@^2.0.6, readable-stream@^2.1.5, readable-stream@^2.2.2, readable-stream@^2.2.8, readable-stream@^2.2.9, readable-stream@^2.3.0, readable-stream@^2.3.3, readable-stream@^2.3.5, readable-stream@^2.3.6:
+"readable-stream@1 || 2", readable-stream@^2.0.0, readable-stream@^2.0.1, readable-stream@^2.0.2, readable-stream@^2.0.4, readable-stream@^2.0.6, readable-stream@^2.1.5, readable-stream@^2.2.2, readable-stream@^2.2.9, readable-stream@^2.3.0, readable-stream@^2.3.3, readable-stream@^2.3.5, readable-stream@^2.3.6:
   version "2.3.6"
   resolved "http://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz#b11c27d88b8ff1fbe070643cf94b0c79ae1b0aaf"
   integrity sha512-tQtKA9WIAhBF3+VLAseyMqZeBjW0AHJoxOtYqSUZNJxauErmLbVm2FW1y+J/YA9dUrAC39ITejlZWhVIwawkKw==
@@ -6503,15 +6254,6 @@ readable-stream@1.0:
     isarray "0.0.1"
     string_decoder "~0.10.x"
 
-readable-stream@^3.0.2, readable-stream@^3.0.6:
-  version "3.3.0"
-  resolved "https://registry.yarnpkg.com/readable-stream/-/readable-stream-3.3.0.tgz#cb8011aad002eb717bf040291feba8569c986fb9"
-  integrity sha512-EsI+s3k3XsW+fU8fQACLN59ky34AZ14LoeVZpYwmZvldCFo0r0gnelwF2TcMjLor/BTL5aDJVBMkss0dthToPw==
-  dependencies:
-    inherits "^2.0.3"
-    string_decoder "^1.1.1"
-    util-deprecate "^1.0.1"
-
 readdirp@^2.0.0:
   version "2.2.1"
   resolved "https://registry.npmjs.org/readdirp/-/readdirp-2.2.1.tgz#0e87622a3325aa33e892285caf8b4e846529a525"
@@ -6750,7 +6492,7 @@ ripemd160@^2.0.0, ripemd160@^2.0.1:
     hash-base "^3.0.0"
     inherits "^2.0.1"
 
-rlp@^2.0.0:
+rlp@^2.2.3:
   version "2.2.3"
   resolved "https://registry.yarnpkg.com/rlp/-/rlp-2.2.3.tgz#7f94aef86cec412df87d5ea1d8cb116a47d45f0e"
   integrity sha512-l6YVrI7+d2vpW6D6rS05x2Xrmq8oW7v3pieZOJKBEdjuTF4Kz/iwk55Zyh1Zaz+KOB2kC8+2jZlp2u9L4tTzCQ==
@@ -6770,11 +6512,6 @@ run-queue@^1.0.0, run-queue@^1.0.3:
   dependencies:
     aproba "^1.1.1"
 
-rustbn.js@^0.2.0:
-  version "0.2.0"
-  resolved "https://registry.yarnpkg.com/rustbn.js/-/rustbn.js-0.2.0.tgz#8082cb886e707155fd1cb6f23bd591ab8d55d0ca"
-  integrity sha512-4VlvkRUuCJvr2J6Y0ImW7NvTCriMi7ErOAqWk1y69vAdoNIzCF3yPmgeNzx+RQTLEDFq5sHfscn1MwHxP9hNfA==
-
 safe-buffer@5.1.1:
   version "5.1.1"
   resolved "https://registry.npmjs.org/safe-buffer/-/safe-buffer-5.1.1.tgz#893312af69b2123def71f57889001671eeb2c853"
@@ -6868,11 +6605,6 @@ selfsigned@^1.9.1:
   dependencies:
     node-forge "0.7.5"
 
-semaphore@>=1.0.1:
-  version "1.1.0"
-  resolved "https://registry.yarnpkg.com/semaphore/-/semaphore-1.1.0.tgz#aaad8b86b20fe8e9b32b16dc2ee682a8cd26a8aa"
-  integrity sha512-O4OZEaNtkMd/K0i6js9SL+gqy0ZCBMgUvlSqHKi4IBdjhe7wB8pwztUk1BbZ1fmrvpwFrPbHzqd2w5pTcJH6LA==
-
 "semver@2 || 3 || 4 || 5", semver@^5.0.1, semver@^5.3.0, semver@^5.4.1, semver@^5.5, semver@^5.5.0:
   version "5.5.1"
   resolved "https://registry.npmjs.org/semver/-/semver-5.5.1.tgz#7dfdd8814bdb7cabc7be0fb1d734cfb66c940477"
@@ -7308,13 +7040,6 @@ string_decoder@^1.0.0, string_decoder@~1.1.1:
   dependencies:
     safe-buffer "~5.1.0"
 
-string_decoder@^1.1.1:
-  version "1.2.0"
-  resolved "https://registry.yarnpkg.com/string_decoder/-/string_decoder-1.2.0.tgz#fe86e738b19544afe70469243b2a1ee9240eae8d"
-  integrity sha512-6YqyX6ZWEYguAxgZzHGL7SsCeGx3V2TtOTqZz1xSTSWnqsbWwbptafNyvf/ACquZUXV3DANr5BDIwNYe1mN42w==
-  dependencies:
-    safe-buffer "~5.1.0"
-
 string_decoder@~0.10.x:
   version "0.10.31"
   resolved "https://registry.npmjs.org/string_decoder/-/string_decoder-0.10.31.tgz#62e203bc41766c6c28c9fc84301dab1c5310fa94"
@@ -7358,13 +7083,6 @@ strip-eof@^1.0.0:
   resolved "https://registry.npmjs.org/strip-eof/-/strip-eof-1.0.0.tgz#bb43ff5598a6eb05d89b59fcd129c983313606bf"
   integrity sha1-u0P/VZim6wXYm1n80SnJgzE2Br8=
 
-strip-hex-prefix@1.0.0:
-  version "1.0.0"
-  resolved "https://registry.yarnpkg.com/strip-hex-prefix/-/strip-hex-prefix-1.0.0.tgz#0c5f155fef1151373377de9dbb588da05500e36f"
-  integrity sha1-DF8VX+8RUTczd96du1iNoFUA428=
-  dependencies:
-    is-hex-prefixed "1.0.0"
-
 strip-json-comments@~2.0.1:
   version "2.0.1"
   resolved "https://registry.npmjs.org/strip-json-comments/-/strip-json-comments-2.0.1.tgz#3c531942e908c2697c0ec344858c286c7ca0a60a"
@@ -7698,13 +7416,6 @@ type-is@^1.6.16, type-is@~1.6.15, type-is@~1.6.16:
     media-typer "0.3.0"
     mime-types "~2.1.18"
 
-typedarray-to-buffer@~3.1.5:
-  version "3.1.5"
-  resolved "https://registry.yarnpkg.com/typedarray-to-buffer/-/typedarray-to-buffer-3.1.5.tgz#a97ee7a9ff42691b9f783ff1bc5112fe3fca9080"
-  integrity sha512-zdu8XMNEDepKKR+XYOXAVPtWui0ly0NtohUscw+UmaHiAWT8hrV1rr//H6V+0DvJ3OQ19S979M0laLfX8rm82Q==
-  dependencies:
-    is-typedarray "^1.0.0"
-
 typedarray@^0.0.6:
   version "0.0.6"
   resolved "https://registry.npmjs.org/typedarray/-/typedarray-0.0.6.tgz#867ac74e3864187b1d3d47d996a78ec5c8830777"
@@ -7715,6 +7426,11 @@ typescript@^2.9.1:
   resolved "https://registry.yarnpkg.com/typescript/-/typescript-2.9.2.tgz#1cbf61d05d6b96269244eb6a3bce4bd914e0f00c"
   integrity sha512-Gr4p6nFNaoufRIY4NMdpQRNmgxVIGMs4Fcu/ujdYk3nAZqk7supzBE9idmvfZIlH/Cuj//dvi+019qEue9lV0w==
 
+typescript@^3.2.2:
+  version "3.5.2"
+  resolved "https://registry.yarnpkg.com/typescript/-/typescript-3.5.2.tgz#a09e1dc69bc9551cadf17dba10ee42cf55e5d56c"
+  integrity sha512-7KxJovlYhTX5RaRbUdkAXN1KUZ8PwWlTzQdHV6xNqvuFOs7+WBo10TQUqT19Q/Jz2hk5v9TQDIhyLhhJY4p5AA==
+
 uglify-es@^3.3.4:
   version "3.3.9"
   resolved "https://registry.npmjs.org/uglify-es/-/uglify-es-3.3.9.tgz#0c1c4f0700bed8dbc124cdb304d2592ca203e677"
@@ -7900,7 +7616,7 @@ utf8@^3.0.0:
   resolved "https://registry.npmjs.org/utf8/-/utf8-3.0.0.tgz#f052eed1364d696e769ef058b183df88c87f69d1"
   integrity sha512-E8VjFIQ/TyQgp+TZfS6l8yp/xWppSAHzidGiRrqe4bK4XP9pTRyKFgGJpO3SN7zdX4DeomTrwaseCHovfpFcqQ==
 
-util-deprecate@^1.0.1, util-deprecate@~1.0.1:
+util-deprecate@~1.0.1:
   version "1.0.2"
   resolved "https://registry.npmjs.org/util-deprecate/-/util-deprecate-1.0.2.tgz#450d4dc9fa70de732762fbd2d4a28981419a0ccf"
   integrity sha1-RQ1Nyfpw3nMnYvvS1KKJgUGaDM8=
@@ -8014,32 +7730,59 @@ wbuf@^1.1.0, wbuf@^1.7.2:
   dependencies:
     minimalistic-assert "^1.0.0"
 
-web3x-es@^3.0.11:
-  version "3.0.11"
-  resolved "https://registry.yarnpkg.com/web3x-es/-/web3x-es-3.0.11.tgz#00ec6eab4c84e48292315108c994292da6a4cf9a"
-  integrity sha512-d0KZdNh9hiw3BjV9pV5PhQ7qP+ECgg0BbTWUbueQ2FGkjw1yJLoAH1nos5OVkE5F6IBbjoDaBmY7wyYTTntmeg==
+web3x-codegen@^4.0.0:
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/web3x-codegen/-/web3x-codegen-4.0.0.tgz#670e6c128df9802294d16587c8f0af0a4c488b46"
+  integrity sha512-Gn/GAahH/xs/oaHRIhCfKyKyP6Jd0zPJD+zDt13SOh1jodmUZzJa97flfXoGbCAuFW3FKYW90AUKhdVi5ULkxw==
+  dependencies:
+    fs-extra "^7.0.1"
+    got "^9.3.0"
+    typescript "^3.2.2"
+    web3x "^4.0.0"
+
+web3x-es@^4.0.0:
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/web3x-es/-/web3x-es-4.0.0.tgz#a4d3a553cdb971bc9eb1072aed5346091f20969d"
+  integrity sha512-pfMVendzCukU471/MnR9CoKI28lZ7Eyrf52tiKV2JJB6j6RWhSXTfrt1OaKuefvo76v0qjm712SprghIQyOdUA==
+  dependencies:
+    "@types/bn.js" "^4.11.2"
+    "@types/node" "^10.12.18"
+    "@types/ws" "^6.0.1"
+    bip39 "^2.5.0"
+    bn.js "^4.11.8"
+    browserify-aes "^1.2.0"
+    elliptic "^6.4.0"
+    hdkey "^1.1.0"
+    idna-uts46-hx "^2.3.1"
+    isomorphic-ws "^4.0.1"
+    node-http-xhr "^1.3.4"
+    pbkdf2 "^3.0.17"
+    randombytes "^2.0.6"
+    rlp "^2.2.3"
+    swarm-js "^0.1.39"
+    tslib "^1.9.3"
+    utf8 "^3.0.0"
+    ws "^6.1.0"
+
+web3x@^4.0.0:
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/web3x/-/web3x-4.0.0.tgz#b597870a69fbe0be516408223e787e3004ab9881"
+  integrity sha512-bBgOyEL4B49FxtNT0IVpTDJKQ8Az4AgggDx4rbj150VylJ1xVscq7yblh2ZjOe4+8GtuD7vxeuYuY0RIb0/I0Q==
   dependencies:
     "@types/bn.js" "^4.11.2"
-    "@types/levelup" "^3.1.0"
     "@types/node" "^10.12.18"
     "@types/ws" "^6.0.1"
-    bigint-buffer "^1.1.2"
     bip39 "^2.5.0"
     bn.js "^4.11.8"
     browserify-aes "^1.2.0"
     elliptic "^6.4.0"
-    fs-extra "^7.0.1"
-    got "^9.3.0"
     hdkey "^1.1.0"
     idna-uts46-hx "^2.3.1"
     isomorphic-ws "^4.0.1"
-    level-js "^4.0.0"
-    levelup "^4.0.0"
-    merkle-patricia-tree "^3.0.0"
     node-http-xhr "^1.3.4"
     pbkdf2 "^3.0.17"
     randombytes "^2.0.6"
-    rustbn.js "^0.2.0"
+    rlp "^2.2.3"
     swarm-js "^0.1.39"
     tslib "^1.9.3"
     utf8 "^3.0.0"
@@ -8320,7 +8063,7 @@ xregexp@4.0.0:
   resolved "https://registry.npmjs.org/xregexp/-/xregexp-4.0.0.tgz#e698189de49dd2a18cc5687b05e17c8e43943020"
   integrity sha512-PHyM+sQouu7xspQQwELlGwwd05mXUFqwFYfqPO0cC7x4fxyHnnuetmQr6CjJiafIDoH4MogHb9dOoJzR/Y4rFg==
 
-xtend@^4.0.0, xtend@^4.0.1, xtend@~4.0.0, xtend@~4.0.1:
+xtend@^4.0.0, xtend@~4.0.1:
   version "4.0.1"
   resolved "https://registry.npmjs.org/xtend/-/xtend-4.0.1.tgz#a5c6d532be656e23db820efb943a1f04998d63af"
   integrity sha1-pcbVMr5lbiPbgg77lDofBJmNY68=