Introduction

The company was a leading telecommunications provider in its country, operating within a relatively limited market where only three companies offered nationwide services. Among them, the market leader held a dominant position across multiple sectors, including telephony, television, and both fixed and mobile internet services. Its website ranked among the most visited nationally, and its online store consistently placed in the top 10 most frequented e-commerce platforms.

The Story

In this project, the role primarily focused on application operation within a team managing a legacy monolithic application written in Java. The system supported a broad range of backend tasks, with its core functionality centered around logistical workflows—covering internal and warehouse processes, communication with external vendors, and order tracking.

As the project progressed, the scope evolved toward rewriting and migrating the application to a modern microservices architecture based on Kubernetes. The main emphasis was on defining core features, processes, and required datasets to support the transition. While the platform itself was provided by another internal team, our team contributed primarily through review tasks, ensuring alignment and quality throughout the rewrite.

The project followed an agile methodology with two-week sprints, and review activities were concentrated around demo sessions. The new platform was built on Kubernetes, with the application rewritten in Kotlin—a modern language running on the Java Virtual Machine (JVM).

The Challenge 

A significant challenge in the project was developing a new admin interface for internal users—functionality that had previously been embedded in the legacy monolithic system. The goal was to create a user-friendly, modern, and maintainable interface while ensuring continuity and satisfaction for internal users. This was achieved by keeping the new interface as close to the original as possible and involving users closely throughout the change process.

Another major challenge was deciding which features and processes to migrate from the old system. Many legacy components were no longer in use, but identifying them required deep knowledge of the application’s functionality and workflows. The lack of proper documentation made this task particularly demanding.

Milestones One of the most notable moments occurred when a business requirement led to moving a function—originally planned as part of the new application—into a separate microservice. After the new application went live successfully, the function was migrated back into the main application a few months later. This unexpected shift underscored the flexibility and adaptability required throughout the migration effort.

The Results

Overall, the project was highly successful. It completed a long-delayed migration and unlocked new opportunities for backend process support. This enabled the implementation of additional delivery options—such as delivery to package points and, in the future, same-day delivery—which marked major milestones. These enhancements had previously been difficult to realize due to the complexity of the legacy application.

The shift to a modular system also facilitated seamless integration with additional vendors. By introducing standardized interfaces, the team was able to deliver quick, targeted solutions within just a few sprints. This flexibility opened up new possibilities for contracting with delivery companies and further strengthened the organization’s logistics capabilities.