diff --git a/src/index.js b/src/index.js
new file mode 100644
index 0000000..e0cbf4b
--- /dev/null
+++ b/src/index.js
@@ -0,0 +1,118 @@
+import * as Types from './types';
+import ConfigField from './config-field';
+import envParser from './env-parser';
+
+class TwConf {
+  static Types = Types;
+
+  /**
+   * @type {Map.<string, *>}
+   */
+  config = new Map();
+
+  /**
+   * @type {Map.<string, string>}
+   */
+  env = new Map();
+
+  /**
+   * @method get
+   * @public
+   * @param {string} key
+   * @return {*}
+   */
+  get(key) {
+    return this.config.get(key);
+  }
+
+  get flatObject() {
+    const result = {};
+
+    this.config.forEach((value, key) => {
+      result[key.replace(/([._-])([a-z\d])/g, str => str[1].toUpperCase())] = value;
+    });
+
+    return Object.freeze(result);
+  }
+
+  toString() {
+    return JSON.stringify(this.config);
+  }
+
+  /**
+   * Create TwConf object
+   * @param {(Map.<string, ConfigField>|Array.<string, ConfigField>[]|object)} confSkeleton
+   * @param {object=} options
+   * @param {boolean} [options.allowUnspecified=true]
+   * @param {boolean} [options.flatOnly=false]
+   * @param {boolean} [options.validationOnDemand=false]
+   */
+  constructor(confSkeleton, options = {
+    allowUnspecified: true,
+    flatOnly: false,
+    validationOnDemand: false,
+  }) {
+    this.options = options;
+
+    /**
+     * @type {Map.<string, ConfigField>}
+     */
+    this.skeleton = null;
+
+    if (confSkeleton instanceof Map) {
+      this.skeleton = confSkeleton;
+    }
+
+    if (confSkeleton instanceof Array) {
+      this.skeleton = new Map(confSkeleton);
+    }
+
+    if (typeof confSkeleton === 'object') {
+      this.skeleton = new Map(Object.keys(confSkeleton).map(key => [key, confSkeleton[key]]));
+    }
+
+    this.skeleton.forEach((value, key) => {
+      if (!(value instanceof ConfigField)) {
+        if (typeof value !== 'object') {
+          const err = new TypeError('Value of ConfigRule must be a object');
+          err.field = key;
+          throw err;
+        }
+
+        this.skeleton.set(key, new ConfigField(value));
+      }
+    });
+
+    if (!this.options.validationOnDemand) {
+      this.validate();
+    }
+  }
+
+  /**
+   * @method validate
+   * @public
+   */
+  validate() {
+    this.env = envParser(this.options);
+
+    const errors = [];
+
+    this.skeleton.forEach((configField, key) => {
+      try {
+        this.config.set(key, configField.validate(this.env.get(key)));
+      } catch (err) {
+        err.field = key;
+        errors.push(err);
+      }
+    });
+
+    if (errors.length) {
+      const newError = new Error('Validation error');
+      newError.errors = errors;
+      throw newError;
+    }
+  }
+}
+
+export default TwConf;
+module.exports = TwConf;
diff --git a/src/index.test.js b/src/index.test.js
new file mode 100644
index 0000000..6bf67cb
--- /dev/null
+++ b/src/index.test.js
@@ -0,0 +1,39 @@
+/* eslint-env mocha */
+/* globals describe, it, before, after, beforeEach, afterEach */
+
+import { expect } from 'chai';
+import TwConf from './index';
+import { StringType } from './types';
+
+describe('twconfig main tests', () => {
+  beforeEach(() => {
+    process.env = {
+      'DATABASE.MONGODB.HOSTNAME': 'localhost',
+      'DATABASE.MONGODB.PORT': '27316',
+      'REDIS:HASH-ALGO': 'testName',
+    };
+  });
+
+  it('simple smoke test', () => {
+    expect(() => {
+// eslint-disable-next-line no-new
+      const conf = new TwConf({
+        'database.mongodb.hostname': {
+          comment: 'hostname of mongodb',
+          simple: 'ams3.digitalocean.com',
+          type: new StringType(),
+          // required: true,
+          preTransforms: [
+            value => String(value),
+          ],
+          validators: [
+            value => value !== 'mongodb',
+          ],
+          default: 'localhost',
+        },
+      });
+
+      expect(conf.get('database.mongodb.hostname')).to.be.equal('localhost');
+    }).not.to.throw();
+  });
+});