April 9, 2026

Senior Java Backend Engineer

Senior • Hybrid

Warsaw, Poland

About Webellian

Webellian is a well-established Digital Transformation and IT consulting company committed to creating a positive impact for our clients. We strive to make a meaningful difference in diverse sectors such as insurance, banking, healthcare, retail, and manufacturing. Our passion for cutting-edge and disruptive technologies, as well as our shared values and strong principles, are what motivate us. We are a community of engineers and senior advisors who work with our clients across industries, playing a deep and meaningful role in accelerating and realizing their vision and strategy.

About the position

As a Senior Java Backend Engineer within Advanced Analytics in the Chief Data & AI Office, you will join the central AI team to build and maintain robust, production-grade AI-enabled services on a global scale. You will work in a cross-functional environment with ML Engineers, Platform Engineers, AI Architects, and DevOps, taking end-to-end ownership from design through reliable operations. In this role, you will help establish consistent engineering standards for security, observability, and delivery, and contribute to scalable internal platforms and shared services that accelerate teams worldwide.

Key responsibilities

  • Design, build, and maintain Java microservices forming the API layer: clean REST interfaces, robust domain models, and maintainable data access patterns using JPA/Hibernate or equivalent.

  • Wrap and expose existing enterprise systems through well-defined service boundaries, enabling incremental modernization without wholesale replacement.

  • Deliver cloud-native services using Docker and Kubernetes (AKS), with attention to scalability, resilience, and cost-efficiency.

  • Build and maintain CI/CD pipelines with automated tests, quality gates, and secure delivery practices using GitHub Actions.

  • Integrate and standardize API exposure via Azure API Management (APIM): usage policies, throttling, authentication/authorization, and versioning.

  • Establish and maintain observability standards using Azure Monitor and Application Insights: dashboards, alerting, distributed tracing, and runbooks.

  • Diagnose and resolve complex issues across microservices, clusters, and pipelines; perform root-cause analysis and preventative improvements.

  • Embed security and resilience: secrets management via Azure Key Vault, least privilege, container security best practices, and disaster recovery patterns.

  • Engineer for regulated environments: audit-friendly practices, traceable changes, reliable logging, and disciplined handling of sensitive data (minimization, access controls, retention).

  • Collaborate with Python/AI engineers to define clear integration contracts between the Java API layer and the Python AI layer.


Required Experience & Skills

  • 5+ years professional backend engineering experience with Java in production environments.

  • Expert-level Java; ideally Spring Boot (primary candidate) with real-world experience; familiarity with Quarkus or Micronaut is a plus.

  • Strong engineering fundamentals: testing strategies (unit, integration, contract), REST API versioning, documentation, code quality, and pragmatic system design.

  • Production experience with Docker and Kubernetes.

  • Strong CI/CD experience (GitHub Actions preferred; ArgoCD or similar also relevant).

  • Familiarity with Azure cloud platforms and services, particularly AKS, ACR, Key Vault, Azure Monitor/Application Insights, and Azure API Management (APIM).

  • Strong experience with PostgreSQL including schema design, migrations (Flyway/Liquibase), and performance tuning fundamentals.

  • Experience integrating with or wrapping legacy enterprise systems via REST, SOAP, or messaging.

  • Familiarity with distributed systems and event-driven architectures using Kafka.

  • Strong troubleshooting skills and an operational mindset.

Ways of Working

  • Comfortable in agile, iterative delivery environments with ownership and accountability.

  • Clear communicator and collaborator across global, cross-functional stakeholders.

  • Proactive learner with pragmatic adoption of AI-assisted developer tools (e.g., GitHub Copilot, Claude Code) to improve developer experience and delivery velocity.

What we offer

  • Contract under Polish law: B2B or Umowa o Pracę

  • Benefits such as private medical care, group insurance, Multisport card

  • English classes available

  • Hybrid work (at least 1 day/week on-site) in Warsaw (Mokotów)

  • Opportunity to work with excellent professionals

  • High standards of work and focus on the quality of code

  • New technologies in use

  • Continuously learning and growth

  • International team

  • Pinball, PlayStation & much more (on-site)



Join a growing team of dedicated professionals! We love to pass on the knowledge to grow excellence, speak our minds without playing politics, and just enjoy hanging around together. If you share our passions - we want to meet you! So go ahead and apply ➡️