Senior Software Engineer

SCYTALYS is a leading software development and system integration company operating internationally, with its main offices in Athens. For more than 30 years we have served the Defense and Security sectors, specializing in the design, development, and integration of mission-critical systems: • Tactical Data Links and Interoperability Solutions • Mission and Command & Control (C2) Systems • Surveillance Solutions We are looking for a skilled and motivated Senior Software Engineer who is passionate about building robust, high-performance software and eager to make an impact on large-scale, mission-critical projects. About the role As a Senior Software Engineer, you will be at the heart of designing and building our systems. You will translate requirements into well-architected, maintainable software and play a key role in shaping the technical direction of the products you work on. Your responsibilities will include: • Designing and developing high-quality software using Java and the Spring Boot ecosystem • Translating technical specifications and requirements into sound, scalable software designs • Architecting and implementing core application features and services • Integrating in-house and third-party components to form complete systems and to extend system capabilities and performance • Optimizing applications for performance, reliability, and resource efficiency • Collaborating closely with fellow engineers, architects, and stakeholders throughout the development lifecycle • Contributing to technical decisions and helping advise on design improvements and solutions to engineering challenges Required Skills • BSc or equivalent in Computer Science, Electrical/Electronics Engineering, or a related field • At least 5 years of professional software development experience • Strong software programming skills in Java (Java 8 and Java 11) • Solid, hands-on experience building applications with Java Spring Boot • Ability to read technical specifications, identify requirements, and produce a software design that satisfies them • Comfortable working on both Windows and Linux systems • Good knowledge of computer networking concepts • Good knowledge of relational databases, including schema design, indexing, and writing and optimizing complex queries • Experience with NoSQL databases (e.g. MongoDB) • Experience integrating databases into applications via JPA/Hibernate, or Spring Data • Experience with application debugging, profiling, and optimization • Good interpersonal skills and the ability to work effectively within a team Nice to have The following are not required but would strengthen your application. We support continuous learning, so you will also have the opportunity to grow into these areas: Language and Frameworks • Familiarity with a modern front-end framework (e.g., Angular, React, or Vue) • Microservices architecture and RESTful / gRPC API design • Reactive programming and a good grasp of multithreading / concurrency • C / C++ programming Tools and Eco-system • Build tooling with Maven or Gradle and version control with Git • Message brokers and streaming (e.g., Kafka, RabbitMQ, ActiveMQ) • Containerization with Docker and orchestration with Kubernetes Data and Persistence • Database performance tuning, query profiling, and execution-plan analysis • Designing and managing database migrations (e.g., Flyway, Liquibase) • Experience with additional databases such as Oracle, MySQL/MariaDB, or SQL Server • Familiarity with caching layers (e.g., Redis) and in-memory data stores • Exposure to time-series, spatial, or geospatial database extensions (e.g., PostGIS) Domain and Standards • Exposure to the Defense, Security, or Command & Control domain • Familiarity with Tactical Data Links or interoperability standards (e.g., Link 16, NATO standards) • Knowledge of geospatial / mapping technologies (e.g., GIS, OGC standards) What we Offer • Competitive remuneration package • Private medical insurance package • Continuous learning and development in new technologies • The opportunity to work on large-scale projects alongside talented people • A hybrid working model offering flexibility and work-life balance