09/29/2026 updated
100 % available
Java Backend Engineer | 10+ Years Experience | Spring Boot | Microservices | Enterprise Apps | SaaS
Borriana, Spain
Only remote
Bachelor of Computer ScienceAbout me
Java Backend Engineer with 10+ years of experience building and supporting enterprise applications and SaaS products. Worked with Java and Spring on long-lived systems with complex business logic - from internal enterprise platforms and digital asset management to logistics and CRM products.
GitHub ActionsSAP CloudAmazon Web ServicesSoftware as a ServiceHibernateSpring FrameworkJUnitPostgreSQLMySQLRedisMockitoSpring BootBackend ProgrammingRestful ApiDocker
Java & Spring Backend Development
Over 10 years of experience building enterprise applications and SaaS products using Java 8-21, Spring Framework, Spring Boot, Hibernate/JPA, and REST APIs. Expertise in both monolithic and microservices architectures, including complex business logic, legacy modernization, and long-term system maintenance.
Database Management & Data Technologies
Broad knowledge of relational and NoSQL databases including MySQL, PostgreSQL, MongoDB, Redis, and Solr. Hands-on experience with data modeling, persistence layer refactoring, and database migrations using Liquibase.
CI/CD & Cloud Infrastructure
Practical experience with CI/CD pipelines using Git, Jenkins, GitLab CI, and GitHub Actions. Proficiency with cloud and infrastructure tools including AWS (EC2, S3, Cognito), Docker, and Linux environments.
Messaging Systems
Experience with asynchronous messaging using ActiveMQ for enterprise application integration.
Testing & Quality Assurance
Application of unit and integration testing using JUnit and Mockito, with demonstrated ability to increase test coverage to 90%+ to improve release confidence and regression detection.
Team Leadership & Mentoring
Experience leading engineering teams of up to 6 members, mentoring junior backend engineers, and supporting their professional growth in enterprise project environments.
Architecture Design
Contribution to backend architecture and integration design across monolithic and microservices systems, including domain boundary definition and reusable infrastructure component design.
SAP Cloud Platform & Chatbot Development
Development of enterprise chatbots using Java 8, Spring Boot, Hibernate, SAP Cloud Platform, and SAP Conversation AI, including building a core chatbot library and automated testing frameworks.
Additional Programming Languages
Basic knowledge of JavaScript and Go, complementing the primary Java backend skill set.
Experience
Professional experience10+ years
Freelancer since2026
Languages
EnglishFluent
Project history
Planned career break after long-term full-time employment. Focused on refreshing backend engineering skills and exploring modern Java, cloud technologies, distributed systems, and AI-assisted development.
- Evolved a JHipster-generated legacy backend into a modular monolith with clearer domain boundaries and reusable infrastructure components.
- Refactored persistence and service layers to reduce duplicated CRUD logic, separate API contracts from domain models, and improve maintainability.
- Introduced reusable testing abstractions and increased unit/integration test coverage to 90%+.
- Tech stack: Java 17, Spring Boot, Hibernate, MySQL, Solr, Redis, Liquibase, Docker, JUnit, Mockito.
- Developed backend microservices for a logistics mobile application platform supporting authentication, onboarding, permissions management, and file handling.
- Contributed to backend architecture and integration design.
- Mentored junior backend engineers and supported their professional growth.
- Tech stack: Java 11, Spring Boot, Hibernate, MySQL/Aurora, AWS (EC2, S3, Cognito), JUnit, Mockito, Liquibase, Docker, Jenkins, Sonar.