Kotlin Back-end Developer

About the Project:

We’re collaborating with a leading company in financial crime prevention and fraud detection. Their platform empowers businesses to assess risk in real time, processing millions of data points per second to detect and prevent fraudulent activity on a global scale.

Currently, we are in the migration phase, modernizing the API infrastructure to ensure seamless compatibility between legacy and new systems. After this phase, we’ll move into platform enhancement, focusing on performance optimization, feature expansion, and system scalability.

You’ll join a highly skilled team working on real-world challenges with high-load systems, modern cloud-native solutions, and advanced communication protocols. This is an excellent opportunity for someone eager to grow fast and gain hands-on experience with cutting-edge technologies in a demanding but rewarding environment.

Project Highlights:

• Current focus: Migration and modernization of legacy API infrastructure.
• Next phase: Platform enhancement, scalability improvements, and feature development.
• Load profile: High throughput, real-time fraud detection.
• Team: 2 Back-End Developers, 1 Solution Architect, 1 Project Manager.
• Methodology: Agile (Scrum), 1-week sprints, daily stand-ups, regular demos.
• Tooling: Slack, Jira, Google Meet.

What You’ll Do:

• Design and implement scalable, cloud-native Kotlin-based microservices.
• Contribute to API migration and performance optimization efforts.
• Leverage Kafka and gRPC for high-throughput, efficient communication between services.
• Work with PostgreSQL (Yugabyte) and jOOQ to optimize data operations.
• Deploy and manage services in AWS and GCP using Kubernetes and Docker.
• Collaborate with DevOps engineers for streamlined, containerized deployments.
• Engage with stakeholders to ensure seamless integration and alignment on goals.

What We’re Looking For:

• Proven experience with Kotlin and Spring Boot in production environments.
• Deep understanding of microservices architecture, API development, and cloud platforms.
• Solid knowledge of Kafka, including Kafka Connect and transactional outbox/inbox patterns.
• Hands-on experience with gRPC and Protobuf for service-to-service communication.
• Proficiency in PostgreSQL, Yugabyte, jOOQ, and SQL performance tuning.
• Experience with Kubernetes, AWS, GCP, and containerized environments.
• Strong problem-solving skills and ability to make architectural decisions.
• Great communication skills and the ability to collaborate with both technical and business teams.

Why Join FreySoft?

🌍 International team within the EU time zone, flexible schedules.

🚀 Cutting-edge technologies and high-load, real-world challenges.

🎯 Growth-focused culture – grow into leadership, own features, or mentor juniors.

💡 Innovative environment – leverage AI/LLM tools to boost development speed and quality.

💰 Competitive compensation based on experience and skills.

🤝 Collaborative and professional team that values initiative, autonomy, and continuous learning.

At FreySoft, we believe in empowering developers to drive innovation and grow through real impact. If you’re passionate about backend development, love solving complex problems, and want to work with some of the most modern tools in the industry – let’s talk.