Senior Java Backend Engineer – Freelance (Barcelona, Hybrid)

Shakers; Barcelona; Híbrido; EUR 55.104 - 82.656; A tiempo parcial

Descripción de la vacante

A technology firm in Barcelona is seeking a Senior Java Backend Engineer for a long-term freelance project. The role involves building and optimizing backend services using Java and Spring Boot within a hybrid work model. Candidates should have over 7 years of Java development experience, strong expertise in microservices, and familiarity with cloud technologies. This role offers significant opportunities for technical leadership and mentoring.

Formación

• 7+ years of Java development experience.
• Strong expertise in Spring Boot and Microservices.
• Experience with Kubernetes and Docker.

Responsabilidades

• Build and optimize back-end services with Java.
• Translate complex business needs into scalable solutions.
• Provide technical leadership and mentor junior developers.

Conocimientos

Java development (Java 8+, ideally 17/21)

Spring Boot

Microservices

REST APIs

Kubernetes

Docker

CI/CD pipelines

Cloud (OpenShift, Azure)

PostgreSQL

Hibernate

Kafka

Spark

Descripción del empleo

Overview

We are looking for a Senior Java Backend Engineer to join a long-term freelance project in Barcelona (hybrid: 3 days onsite, 2 remote).

This role is part of a strategic transformation initiative in the financial sector, modernizing data management systems with cloud-native technologies and agile methodologies.

Responsibilities

• Build and optimize back-end services with Java 8+/11/21, Spring Boot, and Microservices.
• Translate complex business needs into scalable solutions.
• Improve GUI functionality in collaboration with frontend teams.
• Implement best practices in security, compliance, and governance.
• Work with Apache Kafka and Apache Spark for real-time data pipelines.
• Deploy and manage applications in OpenShift and Azure with Kubernetes and Docker.
• Collaborate in agile cross-functional teams (SCRUM, SAFe).
• Provide technical leadership and mentor junior developers.
• 7+ years of Java development (Java 8+, ideally 17/21).
• Strong expertise in Spring Boot, Microservices, REST APIs.
• Experience with Kubernetes, Docker, CI/CD pipelines.
• Cloud knowledge (OpenShift, Azure).
• Familiarity with PostgreSQL, Hibernate, distributed systems.
• Proficiency in Kafka and Spark for real-time streaming.
• Awareness of Angular and testing frameworks (JUnit, Jasmine, Karma).
• Previous work in financial services / trading platforms is a big plus.

Seniority level

Mid-Senior level

Employment type

Contract

Job function

Software Development