How to upgrade an existing information system

When designing the development of complex and related information systems, the use of different technologies for different functional parts of the system can be the optimal solution. Since the late 1990s, we have witnessed the unstoppable growth of web applications. They provide easy installation and upgrades, use of network resources and the Internet, and the ability to work on any operating system and browser. On the other hand, they are more expensive to develop, have worse user experience than desktop applications and are dependent on availability and network quality. Meanwhile, traditional desktop applications overwhelmed most of the major issues. When we add to this the ability to develop classic service applications, RESTful web services and modern web applications that utilize the processor power of a client, we get a palette with which it is possible to develop a flexible and modular information system that utilizes the optimal technology platform for each user request. This paper describes some of the technologies for the development of modern applications and how they are used to upgrade the existing information system.