A high-impact job opportunity for an experienced Java Developer is available in a fast-paced environment.
This role involves designing, developing, and maintaining backend services using Core Java to implement complex business logic. You will work within a large, monolithic codebase (~2M lines) and ensure scalability, maintainability, and high performance. Additionally, you will apply expertise in multithreading, concurrency, and performance optimization.
You will participate in system design, code reviews, and agile Scrum ceremonies, write clean, testable, and maintainable code using TDD and object-oriented principles, debug, profile, and improve distributed and multi-threaded applications, collaborate with other developers and DBAs to troubleshoot and optimize database interactions, contribute to legacy system modernization and long-term platform refactoring, conduct technical interviews and review take-home coding challenges, up hold and promote engineering best practices and coding standards.
Required Qualifications:
* 3+ years of hands-on Java development experience (Java 8 or Java 17)
* Strong knowledge of Core Java, data structures, algorithms, and OOP design
* Proven experience with multithreading, concurrency, and low-latency performance tuning
* Proficiency with relational databases (e.g., Oracle, PostgreSQL), including complex SQL and tuning
* Experience working with large legacy systems and monolithic architecture
* Comfortable working without modern frameworks (e.g., no Spring Boot)
* Familiarity with agile/Scrum methodologies and small collaborative teams
* Strong analytical thinking, problem-solving, and communication skills
Nice to Have:
* Experience with algorithmic problem-solving in production systems
* Interest in legacy modernization and long-term cleanup strategies
* Familiarity with CI/CD, JUnit, Maven, and automated testing tools
Work Environment:
* Hybrid model: 2 days/week onsite at Spaces, Marquês de Pombal (Lisbon)
* Small agile teams (3–5 people per team), part of a ~20-person engineering group
* Long-term, high-impact project with business-critical responsibilities