Senior Java Developer (Smart Home)

Location: Lviv Workplace: onsite Ajax Systems, an international tech company and the largest manufacturer of security systems in Europe. The System Division is responsible for building and developing the Ajax software ecosystem. The team develops and maintains OS Malevich and the Video Management System, builds scalable cloud infrastructure, and creates client applications for multiple platforms, ensuring that all system components work together as a unified ecosystem. The division works with Java, Kotlin, Swift, C, C++, and Python. It includes embedded, cloud, mobile, and desktop engineers who ensure the stable operation of Ajax as a single digital platform. The Smart Home team focuses on integrating Smart Home devices into the Ajax ecosystem, developing cloud-based features such as automation scenarios and integrating third-party devices into the system. The team is also currently working on one of the most complex devices in the Ajax ecosystem, bringing together most of the company's technologies. This is an opportunity to contribute to the development of a sophisticated product that combines multiple technologies and engineering disciplines. Why this role is interesting: opportunity to work on high-load backend systems and distributed architecture. Real impact on core product development and architectural decisions. Modern technology stack and engineering-driven environment. Challenging tasks where performance, reliability and scalability truly matter. Required skills: 5+ years of commercial experience in backend development with Java in an enterprise environment. Strong understanding of Java Concurrency and hands-on experience with concurrent programming in production systems. Solid understanding of SOA, microservices and event-driven architecture. Practical experience with cloud computing platforms. Experience building and supporting high-load, scalable, and highly available systems; Hands-on experience with messaging brokers. Strong understanding of modern backend infrastructure, NoSQL. Practical experience with Kubernetes. Experience with Git, Gradle or othet CI/CD tools. Strong knowledge of unit testing and automated testing approaches. Would be a plus: experience with these technologies: Redis, Netty, Akka, NATS, AWS, Kafka, MongoDB, gRPC. Practical experience with Kotlin. Desire to grow into a team leadership role. What you will do: design and develop core backend services and data pipelines for the product line. Build clean, maintainable, and production-ready code with a strong focus on quality. Contribute to backend architecture, drive technical decisions, and document solutions for reliable deployment and operations. Ensure proper test coverage with unit and integration tests. Take ownership of performance, scalability, and cost efficiency within your domain. Maintain production reliability through monitoring, alerting, dashboards, and runbooks. Investigate and resolve production issues, including deep-dive analysis of complex cases. Work in a strong engineering culture with testing, continuous delivery and DevOps practices. Collaborate closely with product and engineering teams to deliver new features and improve existing services. We offer: the opportunity to suggest and implement your own ideas that directly influence the product and its mass production; A place in a fast-growing company with a motivated and professional team; Competitive salary; Medical insurance; Corporate English classes; The opportunity to participate in Ajax’s internal beta-testing program for security systems; Discounts from partner companies; Discounts on Ajax products. Turn on screen reader support. Ajax Systems is a Ukrainian success story that has grown into a global product. Ajax devices are trusted by more than 4.5 million end users and 330,000 PRO users in over 180 countries. The company provides comprehensive solutions to protect residential and commercial properties of all sizes. Today, Ajax portfolio includes 280 devices for intrusion protection, video surveillance, fire safety, and comfort and automation.