diff --git a/.editorconfig b/.editorconfig
new file mode 100644
index 0000000..6650ea3
--- /dev/null
+++ b/.editorconfig
@@ -0,0 +1,15 @@
+root = true
+
+[*]
+indent_style = tab
+indent_size = 4
+charset = utf-8
+insert_final_newline = true
+trim_trailing_whitespace = true
+
+[*.md]
+trim_trailing_whitespace = false
+
+[{*.{coffee,cson,yml,yaml,jade,pug},package.json,bower.json}]
+indent_style = space
+indent_size = 2
diff --git a/.eslintrc.json b/.eslintrc.json
new file mode 100644
index 0000000..5849b84
--- /dev/null
+++ b/.eslintrc.json
@@ -0,0 +1,35 @@
+{
+	"parserOptions": {
+		"ecmaVersion": 6
+	},
+	"rules": {
+		"indent": [
+			"warn",
+			"tab",
+			{
+				"SwitchCase": 1
+			}
+		],
+		"linebreak-style": "off",
+		"semi": [
+			"error",
+			"always"
+		],
+		"no-unused-vars": "warn",
+		"no-console": "off",
+		"no-redeclare": "warn",
+		"space-before-function-paren": "off",
+		"space-infix-ops": [
+			"error",
+			{
+				"int32Hint": false
+			}
+		]
+	},
+	"env": {
+		"node": true,
+		"es6": true,
+		"mocha": true
+	},
+	"extends": "eslint:recommended"
+}
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..f23ad30
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,74 @@
+
+# Created by https://www.gitignore.io/api/node,windows
+
+### Node ###
+# Logs
+logs
+*.log
+npm-debug.log*
+
+# Runtime data
+pids
+*.pid
+*.seed
+*.pid.lock
+
+# Directory for instrumented libs generated by jscoverage/JSCover
+lib-cov
+
+# Coverage directory used by tools like istanbul
+coverage
+
+# nyc test coverage
+.nyc_output
+
+# Grunt intermediate storage (http://gruntjs.com/creating-plugins#storing-task-files)
+.grunt
+
+# node-waf configuration
+.lock-wscript
+
+# Compiled binary addons (http://nodejs.org/api/addons.html)
+build/Release
+
+# Dependency directories
+node_modules
+jspm_packages
+
+# Optional npm cache directory
+.npm
+
+# Optional eslint cache
+.eslintcache
+
+# Optional REPL history
+.node_repl_history
+
+# Output of 'npm pack'
+*.tgz
+
+# Yarn Integrity file
+.yarn-integrity
+
+
+
+### Windows ###
+# Windows image file caches
+Thumbs.db
+ehthumbs.db
+
+# Folder config file
+Desktop.ini
+
+# Recycle Bin used on file shares
+$RECYCLE.BIN/
+
+# Windows Installer files
+*.cab
+*.msi
+*.msm
+*.msp
+
+# Windows shortcuts
+*.lnk
+
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..0c0bbe7
--- /dev/null
+++ b/README.md
@@ -0,0 +1,26 @@
+# NVL
+[![license](https://img.shields.io/github/license/gluons/NVL.svg?style=flat-square)](https://github.com/gluons/NVL/blob/master/LICENSE)
+[![npm](https://img.shields.io/npm/v/nvl.svg?style=flat-square)](https://www.npmjs.com/package/nvl)
+[![npm](https://img.shields.io/npm/dt/nvl.svg?style=flat-square)](https://www.npmjs.com/package/nvl)
+[![Travis](https://img.shields.io/travis/gluons/NVL.svg?style=flat-square)](https://travis-ci.org/gluons/NVL)
+
+🚮 Replace a blank value with your value.
+
+## Installation
+```
+npm install nvl
+```
+
+## Usage
+```javascript
+const nvl = require('nvl');
+
+let notYet = void 0; // undefined
+let nil = null;
+
+nvl(notYet, true); // -> true
+nvl(nil, 1); // -> 1
+nvl([], [1]); // -> []
+nvl({}, { a: 1, b: 2}); // -> {}
+nvl(false, true); // -> false
+```
diff --git a/index.js b/index.js
new file mode 100644
index 0000000..08af07a
--- /dev/null
+++ b/index.js
@@ -0,0 +1,5 @@
+'use strict';
+
+module.exports = function nvl(value, replaceWith) {
+	return (typeof value !== 'undefined') && (value != null) ? value : replaceWith;
+};
diff --git a/package.json b/package.json
new file mode 100644
index 0000000..b57f39d
--- /dev/null
+++ b/package.json
@@ -0,0 +1,27 @@
+{
+  "name": "nvl",
+  "version": "1.0.0",
+  "description": "Replace a blank value with your value.",
+  "main": "index.js",
+  "scripts": {
+    "test": "mocha"
+  },
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/gluons/NVL.git"
+  },
+  "keywords": [
+    "nvl",
+    "null",
+    "undefined"
+  ],
+  "author": "Saran Tanpituckpong <sarunta@gmail.com>",
+  "license": "MIT",
+  "bugs": {
+    "url": "https://github.com/gluons/NVL/issues"
+  },
+  "homepage": "https://github.com/gluons/NVL",
+  "devDependencies": {
+    "mocha": "*"
+  }
+}
diff --git a/test/tests.js b/test/tests.js
new file mode 100644
index 0000000..bbbfe32
--- /dev/null
+++ b/test/tests.js
@@ -0,0 +1,26 @@
+'use strict';
+
+const assert = require('assert');
+const nvl = require('../');
+
+describe('NVL', () => {
+	it('shoud return `value` when `value` is not blank value', () => {
+		let now = new Date();
+		let emptyArr = [];
+		let emptyObj = {};
+		assert.strictEqual(nvl(now, new Date(0)), now);
+		assert.strictEqual(nvl(emptyArr, [1]), emptyArr);
+		assert.strictEqual(nvl(emptyObj, { a: 1, b: 2}), emptyObj);
+		assert.strictEqual(nvl(false, true), false);
+	});
+	it('shoud return `replaceWith` when `value` is undefined.', () => {
+		let notYet = void 0;
+		let now = new Date();
+		assert.strictEqual(nvl(notYet, now), now);
+	});
+	it('shoud return `replaceWith` when `value` is null.', () => {
+		let nil = null;
+		let now = new Date();
+		assert.strictEqual(nvl(nil, now), now);
+	});
+});
diff --git a/yarn.lock b/yarn.lock
new file mode 100644
index 0000000..8a5a39c
--- /dev/null
+++ b/yarn.lock
@@ -0,0 +1,187 @@
+# THIS IS AN AUTOGENERATED FILE. DO NOT EDIT THIS FILE DIRECTLY.
+# yarn lockfile v1
+
+
+balanced-match@^0.4.1:
+  version "0.4.2"
+  resolved "https://registry.yarnpkg.com/balanced-match/-/balanced-match-0.4.2.tgz#cb3f3e3c732dc0f01ee70b403f302e61d7709838"
+
+brace-expansion@^1.0.0:
+  version "1.1.6"
+  resolved "https://registry.yarnpkg.com/brace-expansion/-/brace-expansion-1.1.6.tgz#7197d7eaa9b87e648390ea61fc66c84427420df9"
+  dependencies:
+    balanced-match "^0.4.1"
+    concat-map "0.0.1"
+
+browser-stdout@1.3.0:
+  version "1.3.0"
+  resolved "https://registry.yarnpkg.com/browser-stdout/-/browser-stdout-1.3.0.tgz#f351d32969d32fa5d7a5567154263d928ae3bd1f"
+
+commander@2.9.0:
+  version "2.9.0"
+  resolved "https://registry.yarnpkg.com/commander/-/commander-2.9.0.tgz#9c99094176e12240cb22d6c5146098400fe0f7d4"
+  dependencies:
+    graceful-readlink ">= 1.0.0"
+
+concat-map@0.0.1:
+  version "0.0.1"
+  resolved "https://registry.yarnpkg.com/concat-map/-/concat-map-0.0.1.tgz#d8a96bd77fd68df7793a73036a3ba0d5405d477b"
+
+debug@2.2.0:
+  version "2.2.0"
+  resolved "https://registry.yarnpkg.com/debug/-/debug-2.2.0.tgz#f87057e995b1a1f6ae6a4960664137bc56f039da"
+  dependencies:
+    ms "0.7.1"
+
+diff@1.4.0:
+  version "1.4.0"
+  resolved "https://registry.yarnpkg.com/diff/-/diff-1.4.0.tgz#7f28d2eb9ee7b15a97efd89ce63dcfdaa3ccbabf"
+
+escape-string-regexp@1.0.5:
+  version "1.0.5"
+  resolved "https://registry.yarnpkg.com/escape-string-regexp/-/escape-string-regexp-1.0.5.tgz#1b61c0562190a8dff6ae3bb2cf0200ca130b86d4"
+
+fs.realpath@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/fs.realpath/-/fs.realpath-1.0.0.tgz#1504ad2523158caa40db4a2787cb01411994ea4f"
+
+glob@7.0.5:
+  version "7.0.5"
+  resolved "https://registry.yarnpkg.com/glob/-/glob-7.0.5.tgz#b4202a69099bbb4d292a7c1b95b6682b67ebdc95"
+  dependencies:
+    fs.realpath "^1.0.0"
+    inflight "^1.0.4"
+    inherits "2"
+    minimatch "^3.0.2"
+    once "^1.3.0"
+    path-is-absolute "^1.0.0"
+
+"graceful-readlink@>= 1.0.0":
+  version "1.0.1"
+  resolved "https://registry.yarnpkg.com/graceful-readlink/-/graceful-readlink-1.0.1.tgz#4cafad76bc62f02fa039b2f94e9a3dd3a391a725"
+
+growl@1.9.2:
+  version "1.9.2"
+  resolved "https://registry.yarnpkg.com/growl/-/growl-1.9.2.tgz#0ea7743715db8d8de2c5ede1775e1b45ac85c02f"
+
+has-flag@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/has-flag/-/has-flag-1.0.0.tgz#9d9e793165ce017a00f00418c43f942a7b1d11fa"
+
+inflight@^1.0.4:
+  version "1.0.6"
+  resolved "https://registry.yarnpkg.com/inflight/-/inflight-1.0.6.tgz#49bd6331d7d02d0c09bc910a1075ba8165b56df9"
+  dependencies:
+    once "^1.3.0"
+    wrappy "1"
+
+inherits@2:
+  version "2.0.3"
+  resolved "https://registry.yarnpkg.com/inherits/-/inherits-2.0.3.tgz#633c2c83e3da42a502f52466022480f4208261de"
+
+json3@3.3.2:
+  version "3.3.2"
+  resolved "https://registry.yarnpkg.com/json3/-/json3-3.3.2.tgz#3c0434743df93e2f5c42aee7b19bcb483575f4e1"
+
+lodash._baseassign@^3.0.0:
+  version "3.2.0"
+  resolved "https://registry.yarnpkg.com/lodash._baseassign/-/lodash._baseassign-3.2.0.tgz#8c38a099500f215ad09e59f1722fd0c52bfe0a4e"
+  dependencies:
+    lodash._basecopy "^3.0.0"
+    lodash.keys "^3.0.0"
+
+lodash._basecopy@^3.0.0:
+  version "3.0.1"
+  resolved "https://registry.yarnpkg.com/lodash._basecopy/-/lodash._basecopy-3.0.1.tgz#8da0e6a876cf344c0ad8a54882111dd3c5c7ca36"
+
+lodash._basecreate@^3.0.0:
+  version "3.0.3"
+  resolved "https://registry.yarnpkg.com/lodash._basecreate/-/lodash._basecreate-3.0.3.tgz#1bc661614daa7fc311b7d03bf16806a0213cf821"
+
+lodash._getnative@^3.0.0:
+  version "3.9.1"
+  resolved "https://registry.yarnpkg.com/lodash._getnative/-/lodash._getnative-3.9.1.tgz#570bc7dede46d61cdcde687d65d3eecbaa3aaff5"
+
+lodash._isiterateecall@^3.0.0:
+  version "3.0.9"
+  resolved "https://registry.yarnpkg.com/lodash._isiterateecall/-/lodash._isiterateecall-3.0.9.tgz#5203ad7ba425fae842460e696db9cf3e6aac057c"
+
+lodash.create@3.1.1:
+  version "3.1.1"
+  resolved "https://registry.yarnpkg.com/lodash.create/-/lodash.create-3.1.1.tgz#d7f2849f0dbda7e04682bb8cd72ab022461debe7"
+  dependencies:
+    lodash._baseassign "^3.0.0"
+    lodash._basecreate "^3.0.0"
+    lodash._isiterateecall "^3.0.0"
+
+lodash.isarguments@^3.0.0:
+  version "3.1.0"
+  resolved "https://registry.yarnpkg.com/lodash.isarguments/-/lodash.isarguments-3.1.0.tgz#2f573d85c6a24289ff00663b491c1d338ff3458a"
+
+lodash.isarray@^3.0.0:
+  version "3.0.4"
+  resolved "https://registry.yarnpkg.com/lodash.isarray/-/lodash.isarray-3.0.4.tgz#79e4eb88c36a8122af86f844aa9bcd851b5fbb55"
+
+lodash.keys@^3.0.0:
+  version "3.1.2"
+  resolved "https://registry.yarnpkg.com/lodash.keys/-/lodash.keys-3.1.2.tgz#4dbc0472b156be50a0b286855d1bd0b0c656098a"
+  dependencies:
+    lodash._getnative "^3.0.0"
+    lodash.isarguments "^3.0.0"
+    lodash.isarray "^3.0.0"
+
+minimatch@^3.0.2:
+  version "3.0.3"
+  resolved "https://registry.yarnpkg.com/minimatch/-/minimatch-3.0.3.tgz#2a4e4090b96b2db06a9d7df01055a62a77c9b774"
+  dependencies:
+    brace-expansion "^1.0.0"
+
+minimist@0.0.8:
+  version "0.0.8"
+  resolved "https://registry.yarnpkg.com/minimist/-/minimist-0.0.8.tgz#857fcabfc3397d2625b8228262e86aa7a011b05d"
+
+mkdirp@0.5.1:
+  version "0.5.1"
+  resolved "https://registry.yarnpkg.com/mkdirp/-/mkdirp-0.5.1.tgz#30057438eac6cf7f8c4767f38648d6697d75c903"
+  dependencies:
+    minimist "0.0.8"
+
+mocha@*:
+  version "3.2.0"
+  resolved "https://registry.yarnpkg.com/mocha/-/mocha-3.2.0.tgz#7dc4f45e5088075171a68896814e6ae9eb7a85e3"
+  dependencies:
+    browser-stdout "1.3.0"
+    commander "2.9.0"
+    debug "2.2.0"
+    diff "1.4.0"
+    escape-string-regexp "1.0.5"
+    glob "7.0.5"
+    growl "1.9.2"
+    json3 "3.3.2"
+    lodash.create "3.1.1"
+    mkdirp "0.5.1"
+    supports-color "3.1.2"
+
+ms@0.7.1:
+  version "0.7.1"
+  resolved "https://registry.yarnpkg.com/ms/-/ms-0.7.1.tgz#9cd13c03adbff25b65effde7ce864ee952017098"
+
+once@^1.3.0:
+  version "1.4.0"
+  resolved "https://registry.yarnpkg.com/once/-/once-1.4.0.tgz#583b1aa775961d4b113ac17d9c50baef9dd76bd1"
+  dependencies:
+    wrappy "1"
+
+path-is-absolute@^1.0.0:
+  version "1.0.1"
+  resolved "https://registry.yarnpkg.com/path-is-absolute/-/path-is-absolute-1.0.1.tgz#174b9268735534ffbc7ace6bf53a5a9e1b5c5f5f"
+
+supports-color@3.1.2:
+  version "3.1.2"
+  resolved "https://registry.yarnpkg.com/supports-color/-/supports-color-3.1.2.tgz#72a262894d9d408b956ca05ff37b2ed8a6e2a2d5"
+  dependencies:
+    has-flag "^1.0.0"
+
+wrappy@1:
+  version "1.0.2"
+  resolved "https://registry.yarnpkg.com/wrappy/-/wrappy-1.0.2.tgz#b5243d8f3ec1aa35f1364605bc0d1036e30ab69f"