Senior Backend (Java) Engineer

We are looking for a Senior Backend Engineer to drive the development and maintenance of the company’s core services. You will become part of a team responsible for designing, developing, and enhancing high-load, scalable backend solutions, integration services, and a microservices ecosystem.
We expect the ideal candidate to bring strong technical expertise, confidence in making architectural decisions, a proactive mindset toward improving existing solutions, and ownership of the product’s technical outcomes.

Requirements:

• 5+ years of commercial experience in Java development.
• Deep knowledge of Java Core, JVM, multithreading, and OOP principles.
• Strong hands-on experience with the Spring Framework (Spring Boot, Spring Data, Spring Security).
• Proven experience in designing and maintaining microservices architecture.
• Solid knowledge of relational databases, SQL, and data schema design principles.
• Experience with Apache Kafka and building event-driven systems.
• Experience with MongoDB or Amazon DocumentDB.
• Experience designing and implementing REST APIs.
• Strong understanding of Distributed Systems principles, CAP Theorem, Consistency Patterns, and Transaction Management.
• Experience with Docker and Kubernetes.
• Understanding of CI/CD principles and modern DevOps practices.
• Experience with at least one cloud platform (AWS, Azure, or GCP).
• Ability to perform technical analysis, assess risks, and propose optimal solutions.
• Strong communication skills and experience working in cross-functional teams.
   

Responsibilities

• Design, develop, and maintain scalable backend services.
• Contribute to the design and evolution of system architecture.
• Develop and support REST APIs and integrations with internal and external systems.
• Optimize service performance, databases, and data processing pipelines.
• Ensure high code quality through unit, integration, and automated testing.
• Write and maintain tests using JUnit, Mockito, and Testcontainers.
• Conduct code reviews and mentor less experienced engineers.
• Analyze and resolve technical issues, defects, and system bottlenecks.
• Collaborate closely with Product, QA, DevOps, and other engineering teams.
• Participate in planning, technical estimation, and task decomposition.
   

Nice to Have:

• Experience designing high-load distributed systems.
• Advanced knowledge of MongoDB/DocumentDB, including schema design, indexing, and query optimization.
• Experience with observability solutions such as Prometheus, Grafana, ELK, and OpenTelemetry.
• Experience building fault-tolerant and resilient systems.
• Practical experience with AWS services (EKS, ECS, RDS, MSK, etc.).
• Experience with Terraform or other Infrastructure as Code solutions.
• Experience in technical leadership or team mentoring.
• Understanding of Domain-Driven Design (DDD) and Clean Architecture.
   

What We Offer:
 

• Flexible work format: remote or from our offices in Kyiv or Warsaw — your choice.
• Full-time employment.
• Standard 5/2 working schedule.
• 24 paid vacation days, sick leave, and health insurance (currently available in Ukraine, with coverage in other locations coming soon).
• A friendly and supportive team where it’s easy to ask questions, share ideas, and grow professionally.
• Coverage of professional events, courses, and learning opportunities.
• Birthday celebrations, team-building activities, and meaningful connections beyond work.
• Zero contribution to the aggressor state or businesses affiliated with it.
   

If this opportunity sounds like a good match for your experience and career goals, we’d love to hear from you — send us your CV and let’s talk!