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Sergio T.ST

Sergio T.

Backend Software Engineer

€280/day
Alicante, ES
3-7 years
Java
SQL
Docker
Spring boot
API

Average response time: 1 hour

About Sergio

Ingeniero backend con 4+ años construyendo sistemas distribuidos en producción.

He trabajado en infraestructura cloud y telecomunicaciones, diseñando microservicios, arquitecturas event-driven y APIs REST que han resuelto con éxito problemas reales de rendimiento, seguridad y escalabilidad a gran escala.

Mi stack principal incluye Java y Spring Boot, Kafka, PostgreSQL, Redis, Docker y Kubernetes, con experiencia adicional en TypeScript y Angular para proyectos full-stack. He aplicado patrones de diseño avanzados, arquitectura hexagonal y buenas prácticas de seguridad como OAuth2, JWT y Keycloak en entornos de producción reales.

En cloud trabajo con AWS y Vercel, con certificación AWS Cloud Practitioner. Tengo experiencia práctica en programación agéntica y actualmente me estoy formando en machine learning e inteligencia artificial aplicada.

Trabajo de forma autónoma, me adapto rápido al contexto del cliente y me implico en entender el problema de negocio antes de proponer soluciones técnicas. Entrego código limpio, documentado y mantenible.

Disponible para proyectos puntuales o colaboraciones recurrentes, principalmente en remoto.

Puedo trabajar en español e inglés.

  • Spanish

    Native or bilingual

  • English

    Fluent

  • Catalan

    Conversational

  • German

    Basic

Remote only
Primarily works remotely

Experience

  • Grupo Aire
    Software Developer
    August 2023 - Today (2 years and 11 months)
    • ● Architected regulatory compliance engine processing 10M+ portability records across 7 systems, automating CNMC reporting via Java Streams and parallel processing, reducing execution time by 80% with 100% XMLvalidation success.
    • ● Engineered distributed rate limiting system with Redis enforcing global API quotas across K8s cluster, achieving sub-millisecond validation and preventing 90% of configuration errors.
    • ● Designed event-driven notification microservice with Kafka, migrating 15+ alert systems from Rocket Chat to Teams with zero downtime, reducing future integration complexity by 70%.
    • ● Automated CI/CD pipeline to Kubernetes using GitLab, reducing deployment time by 85% and errors by 90%, enabling 4x daily deployments and cutting time-to-market by 30%.
    Java API Microservices Apache Kafka Spring boot
  • Inetum
    Software Developer
    March 2022 - September 2022 (6 months)
    • ● Maintained a mission-critical workforce management platform for the French Ministry of Interior, resolving 40+ production incidents and reducing average resolution time from 4 hours to 90 minutes through systematic debugging and monitoring improvements.
    • ● Delivered 5+ scheduling automation features enabling dynamic resource allocation, reducing manual planning overhead by 60% and improving shift coverage accuracy to 98%.

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Education

  • Bachelor´s Degree
    Universitat Oberta de Catalunya (UOC)
    2022
    Bachelor´s Degree
  • Higher Certificate in Multiplatform Software Development
    IES San Vicente
    2022
    Higher Certificate in Multiplatform Software Development
Check out Sergio's education

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