Senior Java Engineer

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

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. Together, we will work on the project leading a test-driven migration of a legacy Java EE application to a modern Spring Boot architecture, including transformation of the data layer from MySQL to MongoDB while ensuring performance parity and incremental validation.

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 and integration tests prior to implementation
• Execute incremental migration with parallel validation
• Ensure performance parity with the legacy application

Requirements:

• Strong experience building enterprise applications, REST APIs, and data access layers using Java and Spring Boot
• Ability to analyze and deconstruct legacy Jakarta EE or Java EE components including EJBs, JPA, and CDI
• Deep understanding of MySQL relational data models and query optimization
• Experience with MongoDB including NoSQL patterns, document modeling, and Spring Data
• Proven track record in TDD and writing comprehensive unit and integration test suites using JUnit, Mockito, and Testcontainers
• Experience with Python for scripting, automation, and migration tooling
• Experience leveraging LLM or AI tools for code analysis, conversion assistance, and documentation generation
• Understanding of Kafka and event-driven architectures for data synchronization
• Familiarity with Docker and Kubernetes for containerized deployments

What`s in it for you?

• Strong community: Work alongside top professionals in a friendly, open-door environment
• Growth focus: Take on large-scale projects with a global impact and expand your expertise
• Tailored learning: Boost your skills with internal events (meetups, conferences, workshops), Udemy access, language courses, and company-paid certifications
• Endless opportunities: Explore diverse domains through internal mobility, finding the best fit to gain hands-on experience with cutting-edge technologies
• Enjoy radical flexibility – work remotely or from an office, your choice
• Care: Medical subscription to Regina Maria, meal tickets of 16 ron net/day worked

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.

In Romania, we welcome top-tier tech talent — whether from our Bucharest office or fully remotely. Tap into deep industry knowledge, grow your career, and make an impact in an empowering environment.

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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.