About the Company:
SmartCore
is a fintech holding building infrastructure for the next generation of payments. Our solutions cover the entire financial operations cycle — from core banking and processing to cards, wallets, and anti-fraud systems.
We are a leading fintech company developing innovative solutions in payment processing and anti-fraud technologies. We create high-tech products that are reshaping the financial landscape and are looking for true professionals ready to tackle complex and ambitious challenges.
About the Project:
You'll join a key team responsible for developing and evolving our core acquiring platform — a complex, high-load, microservices-based system operating 24/7. We handle the entire payment lifecycle, from initiation to clearing, ensuring minimal latency, high fault tolerance, and full compliance with strict security standards (PCI DSS).
What You'll Do:
* Design and develop new microservices and business logic using Kotlin and Java.
* Optimize the performance of existing system components and handle high-load areas of the codebase.
* Make key architectural decisions aimed at improving fault tolerance, scalability, and platform security.
* Integrate with third-party payment systems, banks, and processing centers.
* Work with asynchronous data streams using Kafka and RabbitMQ.
* Conduct code reviews, mentor less experienced colleagues, and promote best development practices.
* Actively participate in R&D — exploring and integrating new technologies into the project stack.
* Write unit and integration tests to maintain a high-quality codebase.
Our Ideal Candidate:
* Has at least 10 years of commercial backend development experience with Java/Kotlin.
* Demonstrates expert-level proficiency in Kotlin: understands idioms, coroutines, functional features, and applies them effectively.
* Possesses deep knowledge of Java Core and the JVM ecosystem.
* Has excellent command of Spring Boot — not only building REST APIs but also understanding its internals, auto-configuration, Spring Security, and Actuator.
* Expert in PostgreSQL — experienced in designing complex data schemas, optimizing queries, understanding transaction isolation levels, and replication mechanisms.
* Experience with MongoDB.
* Hands-on experience building systems with Kafka — understanding broker mechanics, producer/consumer patterns, and message delivery guarantees.
* Familiar with RabbitMQ and Redis (including caching, pub/sub, and distributed locks).
* Experience designing and building distributed, fault-tolerant systems (microservices architecture, CQRS, Event Sourcing).
* Comfortable with modern AI technologies, including AI agents, and capable of applying various LLMs in practice.
* Understanding of networking protocols (TCP/IP, HTTP/2, gRPC).
* Experience with containerization and orchestration tools (Docker, Kubernetes).
* Writes clean, maintainable, and well-tested code.
* Highly autonomous, proactive, and takes full ownership of product quality and outcomes.
* Fluent in Russian (B2 or higher) — required for daily communication within the team.
Nice to Have:
* Experience in fintech or payment processing; familiarity with PCI DSS.
* Experience with reactive stacks (Project Reactor, WebFlux).
* Familiarity with monitoring and tracing tools (Prometheus, Grafana, Jaeger).
* Experience with load testing tools (JMeter, Gatling).
We Offer:
* A competitive salary, discussed individually with each candidate.
* A modern technology stack and minimal bureaucracy.
* Budget for training, professional conferences, and books.
* Corporate access to all top-tier LLMs with maximum configurations.
* A team of passionate experts where your voice will always be heard.
Feel free to apply directly via LinkedIn or by sending your CV to [@] — if you're ready for serious architectural challenges and want to build a product you can be proud of