Senior backend engineer

Join us as Senior Backend Engineer on our live strategy game Supremacy World War III!

At Twin Harbour Interactive we strive to develop high-quality strategy games and make them accessible for all players around the world. In our eyes game development is a promise for fun and entertainment – that’s what we live and aim for!

As a Senior Backend Engineer, you will be responsible for designing, building, and enhancing features for our game platform, focusing on our self-build Java game engine that is interfacing with other services written in Java and PHP, which we constantly extend and improve. Our servers are running on a distributed architecture in the Google Cloud. Your work will align with best practices in stability, performance, scalability, security, and maintainability.

In this role, you will collaborate closely with game designers, producers, and other stakeholders to implement innovative features that enhance the player experience. For this role, you must be fluent in technical and business English.

YOUR MISSION

You will mainly work on the Java Backend of Supremacy World War III, a live strategy game with seasonal releases. However, you need to be comfortable with working in other languages - like PHP. And have an understanding of how Javascript/Typescript works.

• Take ownership for maintaining and extending the Java Backend and actively drive firefighting and quality initiatives.
• Profile and improve performance of a long-running Java game server under live load (GC, threading, slow game loops).
• Work safely in a large, mature codebase: refactor step by step, add tests, keep live games stable through seasonal releases.
• Define SLOs, add metrics/tracing/logging, participate in on-call/incident reviews, and continuously harden reliability & performance for live operations.
• Work closely with game designers and product leads to implement new features with an interest in learning the complementary full-stack technologies.
• Communicate and collaborate within a cross-functional team and with other teams to ensure a smooth daily workflow.
• Actively participate in technical decisions influencing the architecture of our services and platform.
• Mentor and support other engineers through code reviews, pair programming, and knowledge-sharing sessions.
• Drive initiatives to enhance the stability, performance, and scalability of our platform and live games.
• Contribute high-quality, maintainable Java code using a wide range of technologies such as Spring, JUnit5, Gradle, Github, Docker, MySQL, Apache Kafka, Flatbuffers, and Redis.

YOUR BACKSTORY

• 7+ years of proven experience in Java development, demonstrating strong coding and debugging skills.
• Excellent verbal and written communication skills, with the ability to work effectively in a cross-functional team environment.
• Demonstrated ability to effectively integrate AI tools into development workflows for code generation, debugging, and technical research.
• Good understanding of Javascript/Typescript and be familiar with or eager to learn other languages - like PHP, Node.js.
• Excellent analytical and problem-solving skills.
• You have a proactive attitude towards learning new technologies and improving existing skills, including leaving the comfort zone of your programming language.
• You have experience developing and maintaining multi-server, high-load backend services and APIs.
• Deep understanding of computer science fundamentals such as object-oriented design, algorithms, and software architecture patterns.
• Strong automated quality mindset using unit testing, integration testing, and other test automation frameworks.
• You are enthusiastic about games and ideally strategy games.
• Familiarity with SQL and NoSQL databases, including MySQL, PostgreSQL, MongoDB, or similar.
• Experience in popular Java frameworks such as Spring, Spring Boot, JUnit5, and Gradle.
• Experience with cloud platforms (GCP preferred), CI/CD (GitHub Actions), networking, and debugging distributed systems is a plus.
• Hands-on experience with agile methodologies such as Scrum or Kanban.

Why You'll Love Working With Us

A Global Team, A Shared Purpose

Our strength lies in our diversity. With over 30 nationalities represented across our two locations, we’re united by a shared passion for strategy games and a bold vision for the future. We celebrate what makes each of us unique – our perspectives, our stories, and the paths that led us here.

Work Your Way

Whether you're crafting code from a harbor-view desk in Hamburg or fine-tuning design details under the Maltese sun, we support flexible hybrid work models that empower you to do your best work – wherever you are.

Grow With Us

At Twin Harbour, your journey matters. Our Career Path Framework and mentorship culture provide the clarity and feedback you need to take the next step – whether you’re deepening your expertise or branching into new disciplines. We invest in your growth with language courses, e-learning platforms, and support for conferences and training.

We’re Human First

We believe that great teams are built on trust, respect, and good humor. From game nights to casual drinks, quiz nights, and karaoke, we don’t just work together – we connect, play, and support each other like a true crew.

Join Twin Harbour Interactive where Strategy Meets Vision.

Twin Harbour Interactive is a global strategy game powerhouse, shaping the future of long-term multiplayer gaming. With offices in Hamburg and Malta, we design strategy games that bring people together – across borders and generations.

Whether you’re an expert tactician or an imaginative world-builder, there’s a place here for you to grow, thrive, and leave your mark.