Senior Java Engineer

Ciklum is looking for a Senior Java Engineer to join our team full-time in Bulgaria.

We are a custom product engineering company that supports both multinational organizations and scaling startups to solve their most complex business challenges. With a global team of over 4,000 highly skilled developers, consultants, analysts and product owners, we engineer technology that redefines industries and shapes the way people live.

About the role:

As a Senior Java Engineer, become a part of a cross-functional development team engineering experiences of tomorrow. Seeking a developer to lead the test-driven migration of a legacy Java EE application to a modern Spring Boot architecture, including transformation from MySQL to MongoDB.

Responsibilities:

• Analyze existing Java EE components and document business logic
• Design clean, testable Spring Boot services and data access interfaces
• Plan and execute MySQL to MongoDB data model transformation
• Write unit/integration tests prior to implementation
• Execute incremental migration with parallel validation
• Ensure performance parity with legacy application

Requirements:

• Java/Spring Boot - Strong experience building enterprise applications, REST APIs, and data access layers with Spring Data
• Jakarta EE/Java EE - Ability to analyze and deconstruct legacy Java EE components (EJBs, JPA, CDI)
• MySQL - Deep understanding of relational data models and query optimization
• MongoDB - Experience with NoSQL patterns, document modeling, and Spring Data MongoDB
• TDD/Unit Testing - Proven track record writing comprehensive test suites before implementation (JUnit, Mockito, Testcontainers)

Desirable:

• Python - For scripting, automation, and migration tooling
• LLM/AI Tools - Experience leveraging AI for code analysis, conversion assistance, and documentation generation
• Kafka - Understanding of event-driven architectures for data synchronization
• Docker/Kubernetes - Familiarity with containerized deployments

What`s in it for you?

• Regular salary reviews based on performance
• Corporate events: webinars, offline parties, and meetups
• Internal Mobility Program
• Tailored education path (including full access to Udemy, certifications, etc.)
• 25 paid days off: 20 business days of vacation per calendar year + 5 undocumented sick leave days
• Additional health insurance
• 100% company-covered Multisport card, with discounts available for family members

About us:

At Ciklum, we are always exploring innovations, empowering each other to achieve more, and engineering solutions that matter. With us, you’ll work with cutting-edge technologies, contribute to impactful projects, and be part of a One Team culture that values collaboration and progress.
Since expanding to Bulgaria in 2022, we’ve been building a fast-growing team that thrives on learning, collaboration, and innovation. Join us on this exciting journey and help shape the future of our delivery center.
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Explore, empower, engineer with Ciklum!

Interested already? We would love to get to know you! Submit your application. We can’t wait to see you at Ciklum.