Senior Software Engineer

Java Backend Engineer Hybrid, Bucharest, Romania JOB OVERVIEW The Legion application is a high-performance data-driven Java enterprise application that implements sophisticated scheduling and optimization algorithms. It also provides the necessary endpoints for our Web and mobile frontend applications. As a Senior Software Engineer, you will be a member of the team responsible for the implementation and evolution of this application. You will need to be able to write secure, efficient, enterprise-quality Java code, and have a deep understanding of the techniques and technologies that are necessary for scalability and performance. You will also need knowledge and experience with data modeling and relational databases. Our application runs on AWS, so experience with containerization and cloud deployments is desirable. We're using Springboot, Hibernate, MySQL, and JSON, so familiarity with these technologies will be helpful. Frontend experience in JavaScript and Angular and/or React is a big plus. RESPONSIBILITIES AND DUTIES Design and implement: Build scalable, high-performance, and secure features for our Time & Attendance engine, including time-tracking, scheduling rules, overtime logic, and labor compliance calculations. Leverage AI tooling daily: Use AI coding assistants and LLM-powered tools throughout your workflow — code generation, test scaffolding, code review acceleration, documentation, and debugging — and share learnings with your team. Own quality: Write comprehensive unit tests, integration tests, and collaborate on automated test suites. AI-generated code still needs rigorous human review and validation. Drive technical decisions: Participate actively in architecture discussions, propose solutions, and document trade-offs with clarity. Mentor and review: Give substantive code reviews, pair with junior engineers, and model best practices including responsible AI-assisted development. Collaborate cross-functionally: Work closely with Product Management, UX, and QA to translate business requirements into robust technical specifications and BDD scenarios. Troubleshoot production issues: Diagnose and resolve complex bugs in distributed, high-volume environments with urgency and care. Continuously improve: Identify and drive performance, scalability, and reliability improvements across the platform. Uphold security standards: Participate in security reviews and ensure implementations comply with industry standards and internal policies. REQUIRED SKILLS AND QUALIFICATIONS Experience: 5-10+ years of professional software development with deep expertise in Java (or C++) in enterprise or SaaS environments. AI tooling proficiency: Demonstrated, habitual use of AI coding assistants (e.g., GitHub Copilot, Cursor, Claude Code, ChatGPT, Tabnine) in daily development - you should be able to describe specific workflows where AI tooling materially changed how you work. Backend depth: Strong command of Spring Boot, REST API design, Hibernate/JPA, and relational databases (MySQL or equivalent), including query optimization and indexing strategies. Distributed systems: Solid understanding of microservices architecture, asynchronous patterns, and high-volume transaction handling. Cloud & containerization: Hands-on experience with AWS and containerized deployments (Docker, Kubernetes). Software craftsmanship: Deep familiarity with coding standards, code review practices, CI/CD pipelines, and DevOps principles. Testing discipline: Proven ability to write and maintain unit tests, integration tests, and automated test suites - including for AI-generated code. Problem-solving: Demonstrated ability to troubleshoot and debug complex, multi-layered systems independently. Communication: Excellent written and verbal communication skills; able to document technical decisions clearly for both engineers and non-technical stakeholders. Education: Bachelor's or Master's degree in Computer Science, Computer Engineering, or equivalent practical experie