Senior Java Engineer - Poland

Senior Java Engineer SKILLS: Java (17+) | Spring Boot | Microservices | CI/CD | API B2B PLN 120 - 165/ Hour 💰LOCATION: REMOTE, POLAND (occasional travels to Łódź) START DATE: ASAP Key Services and Requirements: A Roadmap to Your Professional Success 🚀 Scope of services: • Define and drive the long-term backend architecture strategy across multiple teams, ensuring clarity, scalability, and alignment • Establish and evolve engineering standards, patterns, and best practices for Java Spring Boot development • Lead cross-team technical initiatives end-to-end, aligning stakeholders across engineering, product, and design • Act as a technical leader and mentor for senior and mid-level engineers through code reviews, design discussions, and hands-on guidance • Collaborate with Product, Frontend, Design, and DevOps leadership to shape the technical roadmap • Proactively identify and address systemic risks such as performance issues, scalability limits, and security gaps • Promote a culture of ownership, observability, and operational excellence • Evaluate and prototype new architectural approaches, influencing future tooling, service design, and engineering practices • Support continuous improvement of backend systems in terms of reliability, maintainability, and performance Here’s a set of skills we require: • 8+ years of professional software engineering experience • At least 5 years of hands-on experience building and operating backend systems using Java and Spring Boot • Expert-level knowledge of: Java (17+) Spring Boot, including advanced topics such as reactive programming, custom configurations, security, and performance tuning • Strong experience designing and evolving microservice architectures, including: service decomposition, inter-service communication (REST, GraphQL, messaging), shared components and codebase organization • Deep understanding of data persistence, including: JPA/Hibernate, relational database design, query optimization, caching strategies (e.g. Redis) • Strong knowledge of API design principles (RESTful); familiarity with GraphQL is beneficial • Solid experience with testing strategies across all levels (unit, integration, end-to-end) • Hands-on experience with: CI/CD pipelines (e.g. GitHub Actions), containerization (Docker), cloud environments (e.g. AWS) • Experience with observability practices, including logging, metrics, tracing, and alerting • Proven ability to work across teams and influence technical direction without direct authority • Strong communication skills — able to explain complex technical concepts to both technical and non-technical stakeholders Nice to have: • Experience defining and scaling engineering standards across multiple teams or domains • Familiarity with event-driven architectures and messaging systems • Practical experience modernizing or refactoring legacy systems • Active usage of AI-assisted development tools (e.g. Copilot, Cursor) as part of daily workflow • Experience shaping engineering culture and mentoring at scale • Exposure to high-availability, high-traffic production environments