Freelancer profile translated to English.

Description

I am a Backend Engineer specialized in Java, Spring Boot, and distributed architectures, with over 6 years of experience developing critical systems for banking, payments, and data platforms.

I have participated in projects related to payment processing, international remittances, card lifecycle management, and analytical data access platforms, working with technologies such as Kafka, RabbitMQ, AWS, Docker, and Kubernetes.

Throughout my career, I have helped improve the performance of high-load systems, eliminate bottlenecks in event-driven architectures, design APIs, and integrate complex enterprise platforms.

I can help you with:

Java and Spring Boot Backend Development
REST API Design
Microservices and Distributed Architectures
Kafka and Event-Driven Systems
Platform and External Service Integration
Performance Optimization and Scalability
Data Platforms and Business Intelligence

I am looking to collaborate on projects where I can contribute technical expertise, architectural vision, and a focus on software quality.

Industry field of expertise

Languages

Spanish
Native or bilingual
Lithuanian
Native or bilingual
English
Fluent

Workplace preferences

Can work on-site

Valencia (up to 50km)

Mercadona,
Senior Java Backend Engineer
January 2026 - Today (5 months)
Development of backend services to facilitate the access, integration, and exploitation of analytical and business data. Design and implementation of APIs for the integration and consumption of information between platforms. Automation and optimization of processes related to Business Intelligence environments. Evolution of data platforms to improve the availability, accessibility, and consumption of information.
Java PostgreSQL BigQuery Spring Boot Spring Batch
Banco Santander,
Senior Java Backend Engineer
February 2025 - January 2026 (11 months)
Development of card payment processing and card lifecycle management systems in high-availability financial environments. Performance optimization of an event-driven architecture using concurrency and parallelism mechanisms, eliminating bottlenecks and significantly increasing processing capacity. Refactoring of complex microservices applying SOLID principles to improve maintainability, scalability, and accelerate the functional evolution of the platform. Design and implementation of transactional mechanisms to ensure data integrity and consistency in critical operations. Integration with payment platforms and tokenization solutions, contributing to compliance with PCI DSS security standards. Participation in the planning and coordination of production deployments, ensuring service continuity.
Java Spring Boot Apache Kafka PostgreSQL Jenkins
PagoNxt (Grupo Santander),
Senior Java Backend Engineer
January 2023 - February 2025 (2 years and 1 month)
Development of remittance and payment processing systems under ISO-20022 standards. Design and implementation of microservices using Java, Spring Boot, PostgreSQL, and RabbitMQ. Performance optimization through caching strategies, reduction of external service calls, and simplification of critical processes. Resolution of critical production incidents and support for high-availability systems, ensuring service continuity. Collaboration with DevOps teams in deployment automation, CI/CD pipeline optimization, and service migration to Kubernetes, improving the platform's scalability and operational efficiency.
AWS Spring Boot Java PostgreSQL RabbitMQ