Java developer in high-load systems

KWAN; Lisboa; On-site; EUR 65,000 - 95,000; Full time

Benefits offered by this job

Relocation package

Visa sponsorship

Career development & learning events

Job summary

KWAN in Lisbon is seeking a Senior Java Developer to drive end-to-end design and hands-on architecture for high-throughput features in a distributed ecosystem.

You will own core backend services, mentor teammates on patterns and quality, and collaborate across teams; relocation and visa sponsorship are available, and a competitive salary with benefits.

Qualifications

• 5+ years of proven hands-on Java and J2EE development.
• Solid knowledge of SQL databases.
• Practical experience with JBoss and Spring Boot.
• Proficiency with Maven build automation.
• Experience with messaging/queuing tech (JMS, Kafka, Pulsar, ActiveMQ).
• Knowledge of distributed systems and high-availability principles.

Responsibilities

• Drive end-to-end technical solution design and hands-on architecture for high-throughput features.
• Own lifecycle of core backend services ensuring scalability and availability.
• Lead domain analyses and translate business goals into system specs.
• Mentor team on architectural patterns, code quality, testing, and best practices.
• Troubleshoot and resolve critical production bugs and edge cases.
• Collaborate with cross-functional teams to align capabilities with milestones.

Skills

Java

J2EE

SQL

Spring Boot

Maven

Messaging/Queuing

Distributed systems

Tools

JBoss

Spring Boot

Maven

Kafka

Pulsar

ActiveMQ

Job description

Описание

We are looking for a Senior Java Developer in Lisbon who's eager to embark on an exciting new opportunity! About KWAN We connect IT professionals with projects that match their skills, professional experience, and goals, then we offer a career progression program, delivered by in-house specialists - our People Experience Partners - to guide them through our journey with us.

Задачи

• Drive end-to-end technical solution design and hands-on architecture for complex, high-throughput features in a distributed ecosystem.
• Own the lifecycle of core backend services, ensuring scalability, resilience, and high availability across distributed components.
• Lead functional and technical domain analyses, translating high-level business goals into precise system specifications and thorough engineering documentation.
• Mentor team members on architectural patterns, code quality, testing standards, and best practices across the Java codebase.
• Troubleshoot, diagnose, and resolve critical bugs and complex edge cases in production and staging environments.
• Collaborate closely with cross-functional team members to align system capabilities with broader project milestones and delivery timelines.

Требования

• 5+ years of proven hands-on experience in Java and J2EE software development.
• Solid knowledge and experience working with SQL databases.
• Practical experience with JBoss and Spring Boot frameworks.
• Proficiency in build automation using Maven.
• Experience or knowledge with messaging and queuing technologies (JMS, Apache Pulsar, Kafka or ActiveMQ).
• Knowledge of distributed systems concepts and high-availability architecture principles.

Условия

• A project that matches your skills and ambitions, as well as your preferences for working policies and culture.
• A competitive salary with awesome benefits and opportunities to leverage your knowledge and network to earn additional income.
• An empowering and respectful work culture enriched with social and learning events.
• A People Experience Partner specially assigned to you - your go-to career guide, responsible for supporting your growth, facilitating training, and ensuring your work-life balance at KWAN.
• A relocation package and visa sponsorship for all our international hires.