Backend Developer (Java/Spring) – iGaming Platform

In Blue Lions, we are building high-quality iGaming products with a mission to empower players and foster a vibrant gaming community.

We are looking for a Senior Back-End Developer with experience in Java, Docker, NoSQL, and Kubernetes who values teamwork, communicates clearly, and takes ownership of what they build.

If you enjoy improving systems and processes, sharing knowledge, mentoring others, and are curious about new technologies (including AI-assisted development), you will fit well with our mindset. If you are open to change, like experimenting with better ways of working, and care about delivering real value to end users, you are very welcome to apply.

From our side, we offer a small team with a flat structure and minimal bureaucracy, where decisions are made quickly and the impact of your work is immediately visible. ?

About the role

Backend Developer (Java/Spring) – iGaming Platform

We are looking for a Backend Developer to join our team and help build a new, state-of-the-art iGaming platform. You will design and develop core backend components, ensuring the platform can handle high throughput, low latency, and real-time data processing for web and mobile gaming applications.

Key Responsibilities

Platform Development

• Design and implement scalable, high-performance software architectures using Spring Boot, with some microservices utilizing Spring WebFlux and Spring Security.
• Develop backend components focusing on high availability, low latency, and scalability. API Development and Integration
• Design and implement RESTful APIs following standard REST conventions.
• Ensure APIs meet security, performance, and maintainability criteria.
• Document APIs using Swagger.

Data Management

• Manage and maintain PostgreSQL and MongoDB databases.
• Optimize database schemas and queries for performance and scalability.
• Use Liquibase for database versioning and migrations.

Messaging and Microservices

• Develop microservices that communicate through Kafka events.
• Work with Avro schema registry for message definitions.
• Solid understanding of microservice architecture principles and best practices

Testing and Quality Assurance

• Write unit and integration tests using JUnit and Mockito with MockMVC.
• Participate in code reviews and contribute to team discussions on design and implementation.

Deployment and Continuous Integration

• Use Docker and Kubernetes for containerization and deployment.
• Work with ArgoCD for continuous deployment and GitOps practices.
• Employ CI/CD and build management tools for efficient delivery.

Documentation and Collaboration

• Adhere to coding standards and document work clearly in the ticketing system.
• Contribute to internal product documentation and suggest improvements.
• Collaborate with cross-functional teams to design robust and scalable solutions.

Required Qualifications

• Minimum 5 years of experience in Java development with Spring Framework.
• Proven experience designing and implementing APIs.
• Strong knowledge of relational (PostgreSQL) and NoSQL (MongoDB) databases.
• Comfortable using version control systems (Git).
• Fluent in English, with excellent written and verbal communication skills.

Preferred / Plus Skills

• Experience with Kafka and Avro schema registry.
• Experience or interest in AI-assisted development (using AI tools or agents to support coding, problem-solving, and development workflows)
• Knowledge of Docker and Kubernetes.
• Familiarity with Spring WebFlux and Spring Security.

Human Skills & Mindset:

• Strong team player who values collaboration, knowledge sharing, and collective ownership of solutions. You actively contribute to a healthy engineering culture and support teammates in achieving common goals.

• Excellent communication skills in English (spoken and written) with the ability to clearly explain technical topics, share ideas, and participate in constructive discussions with engineers, product owners, QA, and designers.

• Proactive problem solver who identifies bottlenecks, addresses inefficiencies, and suggests practical improvements based on real engineering experience.

• Ownership mindset. You take responsibility for the quality, scalability, and reliability of the systems you help build, and you encourage the same level of accountability within the team.

• Comfortable working in an Agile environment where priorities may evolve, and open to experimenting with new approaches to improve team effectiveness and delivery.

Why Join Us

• Be part of building a high-performance iGaming platform from the ground up.
• Work in a collaborative, agile team using modern technologies. Opportunity to influence architecture, tools, and development practices.

We review all applications carefully and will contact candidates whose experience best matches the requirements of the role.

What We Offer:

• 28 days of annual vacation
• 2 paid sick days per year
• Hybrid office work: 2 days of remote work per week
• Option to work remotely from abroad for up to 15 days per year
• Sporting compensation or health insurance benefits
• Small team with a flat structure and minimal bureaucracy, where decisions are made quickly and the impact of your work is immediately visible