Senior Java Full Stack Developer – Tieto Tech… at Tietoevry · Sofia

companyDescription jobDescription MentorMate, part of Tieto Tech Consulting, is looking for a highly skilled and motivated Roaming Business Expert, a professional who will join a project within a Telecom Team for our respectful client BICS. Join the team of our customer BICS – a global telecommunication enabler with a physical network stretching through the globe! Grow your expertise through interacting with A-level mobile carriers from all over the world. Get your hands on the vast network with on land, underwater, and space points of presence. Join our decade-long partnership with BICS to ensure confidence in your future and long-term growth! Tieto-BICS team has been growing since 2010… and we are looking forward to grow with you! Develop your telecom expertise in diverse portfolio of BICS products, including Voice, Cloud, Signaling, LTE, IoT, etc. Enjoy unmatched growth opportunities with BICS vast network and customers around the world. Tieto - BICS team has been growing since 2010… and we are looking forward to growing with you! Responsibilities Design, develop, and maintain scalable applications using Java and modern frontend technologies Lead by example and mentor a development team in day-to-day delivery while continuously improving engineering practices Drive technical discussions and contribute to architecture decisions Collaborate closely with stakeholders, product owners, and cross-functional teams Ensure clean, maintainable, and well-tested code Take ownership of features and deliver end-to-end solutions independently Requirements 5+ years of experience in commercial software development using Java Strong experience with Java 17+, Spring, Spring Boot, Hibernate, and JPA Good knowledge of JavaScript and React.js Experience in API design and development Strong understanding of relational and NoSQL databases, with expertise in writing and optimizing complex SQL queries Solid understanding of design patterns, clean code principles, and testing practices Experience working in Agile/Scrum environments Strong communication skills in English Openness to using modern AI tools in daily development workflows (e.g. GitHub Copilot, Claude Code, ChatGPT) Nice to Have Experience with microservices architecture Cloud and cloud-native experience (AWS is a plus; Azure or Google Cloud also valuable) Experience with OSS/BSS integrations; knowledge of CAMARA and GSMA standards is a strong advantage Experience with Test-Driven Development (TDD) Experience in performance tuning and system optimization Personal Skills Leadership mindset with a hands-on approach Proactive, self-driven, and solution-oriented attitude Strong analytical and problem-solving skills Team player with a collaborative mindset Ability to estimate work accurately and commit to delivery plans qualifications additionalInformation At Tieto, we believe in the power of diversity, equity, and inclusion. We encourage applicants of all backgrounds, genders (m/f/d), and walks of life to join our team, as we believe that this fosters an inspiring workplace and fuels innovation. Our commitment to openness, trust, and diversity is at the heart of our mission to create digital futures that benefit businesses, societies, and humanity. Diversity, equity and inclusion (tietoevry.com)