Senior Java / Spring Developer (f / m)

T-Systems Iberia; España; Presencial; EUR 50.000 - 70.000; Jornada completa

Descripción de la vacante

A leading company in Spain is seeking a Senior Java / Spring Developer to join their dynamic team. The role involves working on challenging international projects, focusing on modern Java and Spring frameworks. Candidates should possess strong skills in concurrency, clean code practices, and cloud-native development. This is an excellent opportunity to contribute to innovative solutions while mentoring junior developers and collaborating with cross-functional teams.

Formación

• Expertise in modern Java versions and language features.
• Extensive experience developing frameworks or libraries.
• Proficient in API-first design approaches.

Responsabilidades

• Join a team to participate in an international project.
• Develop and maintain Java applications using Spring.
• Ensure code quality and adherence to best practices.

Conocimientos

Java

Concurrency

Clean Code

Spring Framework

Observability

Database Management

Cloud-Native Development

DevOps

Herramientas

Kubernetes

Docker

Git

Terraform

Descripción del empleo

We are looking for a Senior Java / Spring Developer (f / m) to join our team in Iberia and participate in a challenging international project.

The position is open in Barcelona, Madrid, Reus, and Andalucia. Would you be interested in joining us? Take on the challenge!

Requirements & Experience

1. Java

• Expertise in modern Java versions and language features (e.g., Java 17+).
• Mastery of Gradle for build management, including custom plugin development.
• Proficient in debugging and profiling (remote / local) complex applications.
• Extensive experience developing frameworks or libraries for internal or public use.
• Solid knowledge of Domain-Driven Design (DDD) principles and patterns.
• Expertise in OOP Fundamentals : Object vs Class, Code reuse, Replace conditions with polymorphism, SOLID principles.

2. Concurrency & Scalability

• Expertise in diagnosing and resolving race conditions in multi-threaded environments.
• In-depth knowledge of Java's concurrency features, including modern techniques (e.g., CompletableFuture, ExecutorService, virtual threads in Project Loom).
• Strong understanding and implementation experience with thread-safe design patterns, synchronization techniques, and non-blocking algorithms.
• Proven ability to optimize concurrent code for performance and scalability in high-traffic systems.

3. Clean Code & Best Practices

• Adherence to Clean Code principles, focusing on simplicity, readability, and maintainability.
• Ability to write self-documenting code and comprehensive unit / integration tests.
• Extensive experience conducting code reviews and promoting coding standards within a team.
• Proficient in API-first design approaches, including tools like OpenAPI.

4. Spring Framework / Spring Boot

• Expertise with both servlet-based and reactive REST APIs, including a deep understanding of request lifecycle.
• Strong understanding of RestTemplate and WebClient for service-to-service communication.
• Experience with creating custom annotations, aspects, and extending Spring Boot frameworks.
• In-depth understanding of JPA, JPA Auditing, Hibernate, L1 / L2 caching, and advanced ORM optimizations.
• Expertise in Spring Security with OAuth2 / OIDC, including client and resource service implementations.
• Solid experience in Spring Cache (local and distributed caching solutions).

5. Spring Cloud

• Advanced knowledge of Spring Cloud Streams and Spring Cloud Functions.
• Experience with Spring Cloud OpenFeign for service integration.
• Expertise in building resilient distributed systems with proven resiliency patterns.
• Proficient in Spring Cloud Config for centralized configuration management.
• Knowledge of distributed locking mechanisms, such as Redisson or Zookeeper.

6. Observability & Monitoring

• Expertise in distributed tracing, metrics, and logging (preferably with OpenTelemetry and Micrometer).
• Skilled in designing and implementing monitoring solutions for event-driven systems.
• Proficient in analyzing and optimizing application performance using monitoring tools.

7. Database Management

• Strong understanding of RDBMS (e.g., PostgreSQL, MSSQL) with hands-on experience in query optimization.
• Proficiency in schema design, including normalization, indexing, and database migrations.
• Familiarity with NoSQL databases and their appropriate use cases.
• Deep understanding of application architecture styles and high-level design.
• Expertise in application design / composition and modular architecture.
• Proficient in designing and implementing microservices following best practices.
• Strong understanding of MVC, CQRS, Transactional In / Out-Box, SAGA, Actor models.
• Expertise in microservices communication patterns like Pub / Sub and event-driven design.
• Solid understanding of anti-patterns and how to avoid them.

9. Cloud-Native Development

• Proficient with Kubernetes for deployment, scaling, and service discovery.
• Experience with containerization tools (e.g., Docker) and orchestration strategies.
• Expertise in local development with Docker Compose or Podman.

10. Application Integration / Messaging Systems

• Extensive experience with messaging systems (e.g., AMQP, MQTT, STOMP, OpenWire).
• Strong knowledge of Spring Integration for application messaging workflows.
• Expertise in designing reliable, scalable messaging architectures.

11. DevOps

• Proficient with Git and version control workflows.
• Expertise in modern CI / CD pipelines, preferably with GitLab.
• Hands-on experience with Helm for Kubernetes deployments.
• Familiarity with Infrastructure as Code (IaC) tools like Terraform.

Technologies (Years for Self-Assessment)

• Java
• OPENAPI
• OPENFEIGN
• OOD / OOP
• CQRS
• OAuth2
• OIDC
• JDBC
• AMQP
• IoC & DI
• JPQL
• SPEL
• PUB / SUB
• SOLID
• Micrometer
• OpenTelemetry

Soft Skills

• Strong ability to mentor and guide less experienced developers.
• Proficient in technical decision-making and architectural governance.
• Excellent communication skills to articulate trade-offs and solutions to stakeholders.
• Adaptability to evolving technologies and willingness to learn new paradigms.
• Strong collaboration skills with cross-functional teams to align technical direction with business goals.