Tell more about the development of microservices for billing and tariffing at MegaFon — how it all happened, what exactly did you do?

In the development of microservices for tariffing and billing at MegaFon, I participated in designing and implementing individual services responsible for calculating service costs and processing payments. The work included:

• Analyzing requirements and collaborating with business analysts to understand tariffing rules.
• Developing REST API for integration with other systems.
• Implementing cost calculation logic considering various tariff plans and promotions.
• Configuring interaction between microservices via message queues (e.g., Kafka).
• Ensuring the reliability and scalability of services.

During the process, I wrote code in Java, participated in writing unit and integration tests, and also handled CI/CD setup for automatic deployment of services.