Senior Java + Python Engineer (Apache Flink)

Fliff unpacks sports gaming into social, free-to-play games for all types of sports fans. We've built a social sports gaming experience that allows users to compete for leaderboard positioning, to achieve badges and build their status within the game.
We are pioneering play-for-fun sports gaming, with our flagship social sportsbook experience that includes sweepstakes promotions and loyalty rewards. We provide sports fans with fun, engaging, and free-to-play alternatives to real money gaming.
We are looking for an experienced Software Engineer to design, develop, and optimize scalable batch and real-time streaming data pipelines using Apache Flink. While our streaming applications are primarily Java-based on Flink, our overall codebase is mostly Python, so familiarity with both languages is important. This role will work closely with our team in Sofia, Bulgaria, and requires comfort collaborating and operating in EEST (Eastern European Time). What You’ll Do

• Design, develop, maintain, and optimize batch and real-time streaming data pipelines using Apache Flink (Java DataStream API, windows, state management, joins, triggers)
• Collaborate on production deployment, monitor, troubleshoot, and tune streaming applications to ensure performance and stability
• Develop scalable microservices for data processing using modern architectural patterns (CQRS, SAGA) (nice to have)
• Build and maintain CI/CD pipelines with automation and testing best practices
• Deploy and manage cloud infrastructure using AWS, GCP, or other cloud providers
• Participate in on-call rotations for production support and incident management
• Collaborate closely with cross-functional teams (engineering, product) to translate requirements into technical solutions
• Mentor junior engineers and drive automation and design thinking initiatives (nice to have)

What We're Looking For:

• Minimum 5 years of professional software engineering experience with strong expertise in Java
• Proficient in Python, at least able to read and write Python code comfortably
• Proven experience with stream processing frameworks, especially Apache Flink; production experience is a strong plus
• Solid experience with streaming technologies such as Apache Kafka
• Strong understanding of both batch and real-time data processing pipelines
• Proficiency in SQL with a focus on PostgreSQL
• Experience with CI/CD pipelines and automated testing frameworks
• Practical knowledge of containerization and orchestration tools: Docker and Kubernetes
• Experience deploying and managing infrastructure on any major cloud platform (AWS, GCP, or similar)
• Comfortable with on-call rotations and production troubleshooting for streaming systems
• Experience with monitoring and alerting tools like Prometheus and Grafana
• Hands-on experience with both stateful and stateless stream processing
• Familiarity with event-driven architecture is highly desirable

Nice to Have

• Experience designing and building microservices architectures using patterns such as CQRS and SAGA
• Familiarity with Apache NiFi for data ingestion and orchestration
• Exposure to infrastructure as code tools like Terraform
• Experience mentoring or leading junior engineers
• Experience designing APIs
• Integration experience with data warehouses or analytics platforms
• Knowledge of Kafka Streams if Flink experience is limited
• Cloud-native application development experience

Benefits:

• Fully remote work environment.
• Professional development opportunities in a dynamic, global setting.
• A supportive, collaborative, and knowledge-driven workplace.
• An engaging and challenging role with the freedom to innovate and develop effective solutions.