bukkaa

Designed and delivered a medical reporting service orchestrating multiple internal services, enabling flexible report generation for different patient data scenarios. The process involves several other internal services using both synchronous and asynchronous communications. The approach was flexible enough to generate different types of the reports populating different kinds of data about the patient using Jasper Reports.

Designed and implemented fault-tolerant ETL platform migrating 9TB+ of enterprise data from 15+ legacy systems into Microsoft Dataverse (Dynamics 365 platform); Developed multithreaded batch-processing pipelines with recovery checkpoints and resilient restart mechanisms, allowing safe resumption from the last committed batch; Designed and implemented Reporting and Reconciliation modules using Jasper Reports for processing analytics and source-to-target consistency validation; Optimized JVM Garbage Collection for long-running ETL workloads, stabilizing memory consumption at ~4.5GB and eliminating container OOM crashes caused by unstable 8GB memory spikes; Participated in architecture design, release tagging, deployment and production support activities across distributed ETL services.

Developed backend integration platform connecting POS devices with cloud-based delivery and menu management systems; Designed and implemented serverless menu synchronization application using Azure Functions for automated synchronization between cloud platform and distributed POS environments; Integrated third-party delivery platforms and external APIs (PAPU.io) into existing backend ecosystem using Spring Boot and asynchronous processing flows; Participated in development and support of serverless License Management application for distributed POS infrastructure; Worked with Azure Cloud stack, GCP, PostgreSQL and DynamoDB in cloud-native integration environment.

Contributed to backend development of Portfolio Management and Billing & Fees platforms processing 10TB+ of financial data and 20M+ customer accounts; Participated in modernization of 7-year-old legacy monolith into distributed microservices architecture with ~8 services, asynchronous integrations, distributed caching and event-driven communication using IBM MQ and JMS; Collaborated on migration of business-critical logic from Oracle stored procedures into Java backend services using Spring Boot, Spring Data JPA and Hibernate; Migrated backend services to Java 17 and cloud-native Kubernetes-based deployment pipelines, reducing build times from ~22-30 minutes to ~3-4 minutes; Optimized SQL queries, batch-processing flows and JVM Garbage Collection configuration for high-volume financial workloads; Served as primary backend knowledge holder during team expansion from 1 to 5 engineers, onboarding new developers and maintaining technical documentation; Mentored backend internship direction for ~1 year; interns later joined project team as independent mid-level backend engineers; Participated in production support and observability activities using Splunk, Datadog and Jenkins.

Backend development and support of high-load IoT platform 'Eltex Smart Control System'; Analysis of competing products and market situation; Tasks decomposition and assignment; Playing active role in existing and new applications architecture design; Production deployment support; Refactored legacy codebase by introducing Spring Framework and DI, improving modularity, flexibility, and overall code quality; Contributed to platform architecture design with a focus on gradual transition towards microservices; Designed and implemented a monitoring system for IoT devices and controllers using Kafka and Zabbix, enabling real-time health checks and alerting (SMS, WhatsApp, email); delivered as a commercial module; Developed a licensing service for managing platform and extension modules, including license generation, validation, fraud detection, and integration with 1C; enabled flexible pricing and feature control; its flexible and extensible architecture allowed rapid adaptation and rollout across multiple business units with minimal changes; Set up centralized logging and alerting pipeline using Fluentd, Elasticsearch, Kibana, and ElasticAlert, improving observability and incident response.

Backend development and support of large-scale financial processing services; Development and support of internal libraries and tools for in-company use only.