const Sequelize = require('sequelize');
const env = process.env.NODE_ENV || 'development';
const config = require('../config/config.json')[env];

const sequelize = new Sequelize(config.database, config.username, config.password, config);

module.exports = sequelize;

@@ -156,16 +156,139 @@
 uelize =
+ (() =%3E %7B%0A%09if (config.use_env_variable) %7B%0A%09%09return new Sequelize(process.env%5Bconfig.use_env_variable%5D, config);%0A%09%7D%0A%0A%09return
  new Seq
@@ -353,16 +353,22 @@
 config);
+%0A%7D)();
 %0A%0Amodule

Implement use_env_variable in main app logic