06/11/2026 updated
100 % available
Senior Backend Engineer | Java, Spring Boot, Microservices, AWS, Kafka, Kubernetes
Tarragona, Spain
Only remote
BSc in Software EngineeringAbout me
Senior Backend Engineer with 9 years’ experience modernizing and scaling web platforms. Strong Java/Spring expertise, with production work across Ruby/Rails, REST APIs, microservices, AWS, Kubernetes, SQL, event-driven systems, observability, reliability, and AI-assisted development.
Application Programming Interfaces (APIs)PostgreSQLMongoDBOpenShiftRuby On RailsRubyTypeScriptSpring CloudSpring BootBackendBackend ProgrammingKubernetesOptimization AlgorithmsApache KafkaFront End Software Development
Java & Spring Boot
Extensive experience in developing backend solutions with Java and Spring Boot, including the implementation of REST APIs and microservices for mission-critical platforms across various industries.
Cloud & Platform Engineering (AWS, OpenShift, Kubernetes)
Expertise in deploying and managing services on AWS (EC2, EKS, IAM, S3), OpenShift, and Kubernetes, with a focus on scalable and reliable production systems.
Microservices & REST APIs
Development and maintenance of microservices architectures and REST APIs to support product development and application modernization in agile environments.
Messaging & Streaming (Kafka)
Use of Apache Kafka for the development of event-driven and message-based systems in production-critical environments.
Databases & Data Persistence
Experience with relational and non-relational databases such as PostgreSQL, MySQL, Oracle SQL, MongoDB, and Elasticsearch for search and analytics requirements.
CI/CD & Delivery
Use of GitHub Actions, Jenkins, and Bamboo to automate build, test, and deployment processes and improve deployment reliability.
Frontend Technologies
Proficiency in modern frontend frameworks such as Next.js, React, and Angular for developing full-stack solutions.
Observability & Monitoring
Use of Grafana, Prometheus, and ELK to monitor and analyze system performance and operational stability.
Testing
Application of testing frameworks such as JUnit, RSpec, and Capybara to ensure software quality in regulated and agile environments.
TypeScript & NestJS
Development of backend services using TypeScript and NestJS as part of modern full-stack architectures.
Experience
Professional experience5 - 10 years
Freelancer since2026
Languages
EnglishFluentSpanishNative speaker
Project history
Modernisierung von Legacy-Ruby-on-Rails- und React-on-Rails-Anwendungen durch Neuentwicklung zentraler Flows mit Next.js, NestJS und Rails API. Aufbau und Wartung von Backend-Services und APIs, Verbesserung der Anwendungsperformance um bis zu 10x durch Caching-Strategien und Latenzreduzierung sowie Optimierung der Deployment-Zuverlaessigkeit.
Entwicklung von Backend-Loesungen fuer kritische oeffentliche Plattformen der Regierung Kataloniens mit Java 17, Spring Boot, Hibernate, Elasticsearch und Kafka. Bereitstellung und Wartung von Diensten auf OpenShift-Clustern auf AWS. Neuentwicklung einer geschaeftskritischen Back-Office-Presseplattform sowie Aufbau einer Bildungsplattform fuer arbeitssuchende Buerger.
Entwicklung und Weiterentwicklung mehrerer geschaeftskritischer Anwendungen fuer einen grossen nationalen Bankkunden in den Bereichen Steuern, Zahlungen, Recht und interne Tools. Zusammenarbeit mit Stakeholdern zur Anforderungserhebung und Loesungsvalidierung sowie Mentoring von Junior-Entwicklern.