Vol. 7, Issue 1, Part A (2025)

One of the eight main indicators of the software system effectiveness is its maintenance. The main goal of software system maintenance is to preserve the functionality of the software system over time. Software system maintenance is a broad activity and includes the correction of errors that have arisen periodically after the software system is delivered to the customer, increasing its functionality, removing obsolete functions and introducing new ones, etc. The software maintenance and its costs constitute more than 20-25% of the total expenses of the software system. There are various models of the software system life cycle, and the choice of the model depends on the given project. Each software engineer must have sufficient knowledge in this area to choose the appropriate model of the software system life cycle based on the content and requirements of the project. In these models, the last and most important stage of the software life cycle is software system maintenance. The main purpose of this work is to study the process of software system maintenance and its main issues, types, categories, stages, and to develop a conceptual model based on them. The goal is to achieve an efficient software system based on the conceptual model.