Senior Software Engineer (Java, GCP)

Capgemini; Katowice; On-site; PLN 180,000 - 300,000; Full time

Benefits offered by this job

Hybrid work model

Home office package with equipment

Job summary

Capgemini is seeking a senior Java backend engineer in Katowice to design and build microservices using Java and Spring, with a focus on performance, scalability, and test automation.

You will work on RESTful APIs, cloud collaboration (GCP, Terraform), and contribute to architecture discussions in a hybrid work model.

Qualifications

• 5+ years of Java development with strong backend focus.
• Solid knowledge of core Java concepts and memory management.
• Experience with concurrency, futures and asynchronous programming.
• Hands-on Spring Boot and Spring Data expertise.
• Experience in designing REST APIs and microservices.
• Familiarity with GCP and cloud-native tooling.
• Proactive in identifying memory leaks and performance issues.
• Experience with unit/integration testing (JUnit, Mockito).

Responsibilities

• Designing and developing backend systems using Java and Spring ecosystem.
• Building and maintaining microservices-based architectures.
• Writing high-quality, maintainable code with focus on performance and scalability.
• Implementing unit and integration tests (JUnit, Mockito).
• Analyzing and resolving performance issues (memory leaks, GC behavior).
• Collaborating with DevOps on cloud infrastructure (GCP, Terraform).
• Participating in code reviews, technical discussions, and architecture design.

Skills

5+ years Java

Core Java knowledge

Memory management

Concurrency

Future/CompletableFuture

Spring Boot

Spring Data

REST APIs

Tools

Docker

Kubernetes

Jenkins

GitLab CI

Terraform

Cloud (GCP)

Job description

Engineered and maintained backend systems using Java and Spring ecosystem with a strong focus on microservices architecture, ensuring high code quality, performance, and scalability while implementing automated tests and resolving performance-related issues.

Your Tasks

• Designing and developing backend systems using Java and Spring ecosystem
• Building and maintaining microservices-based architectures
• Writing high-quality, maintainable code with a strong focus on performance and scalability
• Implementing unit and integration tests (JUnit, Mockito)
• Analyzing and resolving performance issues (e.g., memory leaks, GC behavior)
• Applying modern Java features and best practices in daily development
• Collaborating with DevOps teams on cloud infrastructure (GCP, Terraform)
• Participating in code reviews, technical discussions, and architecture design

Your Profile

• 5+ years experience in Java development
• Strong knowledge of core Java (collections, access modifiers, exception handling)
• Understanding of Java memory model, memory structure, and Garbage Collection
• Engineering experience and a systems‑thinking mindset
• Ability to identify and resolve memory leaks
• Solid knowledge of concurrency (synchronised, volatile, atomic types)
• Experience with Future / CompletableFuture
• Future and multithreading concepts
• Familiarity with modern Java features (records, sealed classes, default methods, virtual threads – at least theoretical)
• Hands‑on experience with Spring Boot and Spring Data
• Experience in designing and implementing REST APIs and microservices
• Practical experience with unit and integration testing (JUnit, Mockito)
• Understanding of microservice architecture principles
• Exposure to GCP

Nice To Have

• Docker, Kubernetes (cloud‑native approach)
• Messaging systems (Kafka, ActiveMQ)
• CI/CD tools (Jenkins, GitLab CI)
• Basic knowledge of Terraform / Infrastructure as Code
• Experience working in Agile (Scrum/Kanban)
• Experience in distributed systems and observability tools
• Experience working with high‑load systems

What You’ll Love About Working Here

• Enjoy hybrid working model that fits your life – after completing onboarding, connect work from a modern office with ergonomic work from home, thanks to a home office package (including laptop, monitor, and chair). Ask your recruiter about the details.
• Access to over 70 training tracks with certification opportunities (e.g., GenAI, Architects, Google) on our NEXT platform. Dive into a world of knowledge with free access to Education First languages platform, Pluralsight, TED Talks, Coursera and Udemy Business materials and trainings.
• Practical benefits: private medical care with Medicover with additional packages (e.g., dental, senior care, oncology) available on preferential terms, life insurance and 40+ options on our NAIS benefit platform, including Netflix, Spotify or Medicover Sport.