Senior Java Engineer
Alex Staff Agency · Montenegro · Slovenia · Slovakia +3 · Remote
The position is open for a global, publicly traded AdTech market leader. The company's platforms handle over 1 trillion requests per day, operating within a highly optimized real-time cloud architecture across dozens of servers and processing terabytes of data daily.
The engineering team focuses on intense performance optimization, low-latency infrastructure, asynchronous data streaming, and cutting-edge GenAI research and development.
- Salary: upto $5,000 USD / month.
- Format: Full-time. Hybrid (Budva, Montenegro) or 100% Remote globally
- Contract Type: B2B Contract
Responsibilities
- Design, scale, and maintain real-time advertising bidding systems (DSPs, RTB Exchanges, and SSP platforms).
- Optimize backend services using Java (Spring Boot / WebFlux) and Go (Golang) to meet strict low-latency SLA/SLO targets.
- Build and manage data-intensive architectures utilizing high-load storage solutions (Aerospike, ClickHouse) and event-driven messaging (Apache Kafka).
- Participate in R&D initiatives involving GenAI, integrating Agentic AI frameworks (LangChain, LangGraph, N8N) for workflow automation and predictive analytics.
- Take full ownership of features end-to-end, contributing to the frontend layer (React / TypeScript) for internal tools and dashboards when required.
- 5+ years of commercial software development experience with Java as the primary language.
- Deep knowledge of the Spring ecosystem (Boot, Data, MVC, Security, Cloud) and strong practical experience with reactive/asynchronous programming (Spring WebFlux / Project Reactor).
- Solid understanding of distributed systems, concurrency, and performance tuning at the JVM level.
- Strong verbal English skills at B2 level or higher, with the ability to explain architectural decisions and collaborate directly with a global engineering team during voice calls.
- Location outside of the Russian Federation due to contractual and payment restrictions. Candidates from Belarus are eligible only if they possess an active legal entity/IP in Georgia or Europe for international payments.
- Commercial programming experience or strong familiarity with Go (Golang).
- Hands-on experience with high-load and Big Data tools including Apache Kafka, ClickHouse, and Aerospike.
- Real-world experience or deep interest in LLMs and AI orchestration tools such as LangChain, LangGraph, or N8N.
- Familiarity with frontend development using ReactJS and TypeScript.
- Opportunity to work on production infrastructure handling 1 trillion + daily requests.
- Work within a team of senior engineers with direct impact on the platform's architecture.
- Choice between a fully remote schedule or a hybrid format from the office in Budva, Montenegro.
- Stable monthly payments in USD via international B2B contracts.
Skills
- Java
- Generative AI
- Spring Boot
- Webflux
- Go
- ClickHouse
- Kafka
- LangChain
- LangGraph
- n8n
- React
- TypeScript
- Spring
- Spring WebFlux
- JVM
- LLM
More jobs at Alex Staff Agency
All 7- Senior Product Owner (Integrations & Platform)Alex Staff Agency · Rotterdam, Zuid-Holland, Netherlands1mo ago
- Security Engineer / Staff EngineerAlex Staff Agency · Worldwide2mo ago
- Kernel Developer - KernelCare ELS TeamAlex Staff Agency · Argentina · Brazil · Mexico +32mo ago
- Database Reliability EngineerAlex Staff Agency · Poland · Georgia · Armenia +33mo ago
- Engineering Manager (Back Office & Integration)Alex Staff Agency · Rotterdam, South Holland, Netherlands4mo ago
Similar roles
- Agentic AI Co-Founder / Head of Engineering (100 % remote) (m/f/d)EWOR · Podgorica, Montenegro4d ago
- Senior RevOps EngineerImprovado · Montenegro4d ago
- Senior Product Manager (Remote, Contract)INFUSE · Montenegro6d ago
- Senior Full-Stack Developer (Angular / .NET Core)Resourceful Talent Group · Bratislava, Bratislavský kraj, Slovakia · Bucharest, București, Romania · Belgrade, Beograd, Serbia +1710d ago
- Forward Deployed Engineering Expert (part-time)TripleTen · Podgorica, Montenegro, Montenegro11d ago
- SEO & Website Optimization Specialist (SEO / GEO · Technical · Analytics)Improvado · Montenegro12d ago