Senior Scala/Java Engineer

Turnkey isn’t just our biggest team — it’s the engine room of everything we build.
It’s the tech our partners bet their business on: no patchwork, no plug-ins. Just one battle-tested ecosystem designed to launch, grow, and lead in the most dynamic markets.
Turnkey unites VeliHorizon (our core platform), VeliX (the experience layer), and VeliPayments — the trio powers every player's journey and operator’s next big leap.

We invite a ​​​​​​Senior Scala/Java Engineer to join the VeliHorizon (Promo) team.
VeliHorizon — our battle-tested platform built on real gaming floors. High-performance, microservices at its core, API-first by design — it keeps operations smooth, data sharp, and transactions flying.
Every click, spin, and payout runs through Horizon — proven in the toughest conditions, powering thousands of moments a second. Built by cross-functional teams who own every detail — from first idea to live performance.

In this role, you will:

• Drive design, implement, extend, test, deliver, and maintain domain-specific business features in production.
• Optimize and refactor the existing codebase and data models.
• Participate in SRE activities, including monitoring, troubleshooting, production releases and housekeeping.
• Respond to and investigate complex problems within the team's area of responsibility and cross-team areas by retrieving and analyzing heap dumps, logs, SQL queries, reports, and charts.
• Improve internal common libraries and frameworks.
• Collaborate with team members and external stakeholders to address technical and business challenges, drive the product's feature development and actively seek feedback.
   

Skills and experience you will need:

• Proficiency in Java with practical experience using Quarkus(Rest, Mutiny, Reactive PG SQL), or similar Spring Framework, Vert.x
• Scala development experience required. Akka or ZIO will be a huge advantage
• Strong understanding of functional programming principles and best practices.
• Practical experience of JVM application garbage collection, memory management, understanding and troubleshooting
• Solid experience with Kafka (event-driven architecture, message delivery semantics, stream processing).
• Strong command of relational databases, especially PostgreSQL.
• Experience designing and maintaining RESTful HTTP APIs for client communication.
• Hands-on experience with gRPC for efficient inter-service communication.
• Understanding and application of Clean Architecture principles in designing modular and maintainable systems.
• Experience working in distributed microservice environments with domain-driven service decomposition.
• Understanding of asynchronous messaging patterns and event-driven communication, especially over Kafka.
• Good understanding of CAP theorem, message delivery strategies (at-most-once, at-least-once, exactly-once), and fault tolerance in distributed systems.
• Hands-on experience deploying and managing applications in Kubernetes, using containerd or other container runtimes.
• Software Design and Engineering Best Practices:
• Deep understanding of software design principles: SOLID, GRASP, and other key OOP/FP paradigms.
• Ability to write clean, maintainable, and well-tested code.
• Experience with concurrent and parallel programming, thread management, and async task orchestration
• Experience with near-real-time stream processing (millions of records per second/minute). Focus on throughput and latency optimization

Note: This is not a “big data” (Hadoop/Spark) batch processing role, but rather stream-oriented, high-load system development.

Will be a plus:

• A relevant university degree in Computer Science, Software Engineering, or a related field is preferred.
• Experience with Akka, ZIO, and the Slick library
• Familiarity with Elasticsearch and its integration in search-heavy services.
• Experience with Grafana, Prometheus (ViktoriaMetrics), ELK, or other monitoring solutions. 
• Familiarity with CI/CD workflows and observability tools.Familiarity with analytical databases, especially ClickHouse.

Hiring process: Intro Call with TA Specialist → Technical Interview (with Live coding session)→ Final interview → Offer

Benefits:
Level up daily.  Real mentorship, a clear career path, and support to lead your product. 
Battle-tested tech stack. Work with what we bet on: microservices, serverless, SRE strength.
Health comes first. Insurance and 10 days' sick leave — because your health is a priority.
Work your way. Remote, hybrid, Kyiv office — find your rhythm.
Time off that matters. 20 days paid vacation, public holidays — to recharge your way.
Build your brand. Share your story, grow your voice — inside and out.
Culture with a pulse. Team offsites, community events, and the energy of people who care.