Senior Java Backend Engineer

About the Company

We’re Source Angel, a Danish-rooted software company with development centers in Ukraine, Poland, and Romania. For over 8 years, we’ve been building dedicated tech teams for global clients, focusing on long-term partnerships and a strong people-first culture.

We foster an environment of respect, transparency, and professional growth, offering engineers freedom with responsibility, collaborative Scandinavian leadership, and an international mindset.

About the Project

You’ll join a newly formed core team that is rebuilding a widely-used automotive SaaS platform from scratch, using modern technologies and AI-first development principles. The system supports over 1,500 car repair shops across Europe—from workshop management to integrations with finance, logistics, and more.

The client is part of a global software group (190+ companies in 34 countries), providing long-term stability, strategic support, and room for innovation, while keeping full autonomy in the local product strategy.

This is a long-term greenfield modernization project with high technical standards and a strong emphasis on scalability, security, clean architecture, and future AI integration.

What You’ll Do

• Design and build microservices using Domain-Driven Design (DDD)

• Define and maintain REST/GraphQL APIs with OpenAPI or similar

• Collaborate with DevOps to implement CI/CD, containerization, and GitOps workflows

• Set up observability and metrics using Prometheus, Grafana, Loki, Jaeger

• Integrate security/auth using OAuth2, OIDC, SCIM

• Participate in architecture reviews, mentoring, and documentation

• Help migrate legacy systems to a new cloud-native platform

• Work closely with a Danish-based tech lead and distributed team

Tech Stack

• Languages: Java 21 + Spring Boot 3 (main), also Go / Node.js in parts

• Infrastructure: Docker, Kubernetes (Helm/Terraform), OVH or managed cloud

• Databases: PostgreSQL, MongoDB, Cassandra

• Messaging: RabbitMQ (initial), Kafka (future)

• CI/CD: GitHub Actions, ArgoCD, GitLab CI

• Security: Zitadel (OAuth2/OIDC)

• Observability: Prometheus, Loki, OpenTelemetry, Jaeger, Grafana

• Docs/Planning: Jira, Confluence, Markdown/AsciiDoc

What We’re Looking For

• 5+ years of backend development experience

• Proficiency in Java and microservices architecture

• Solid experience with Kubernetes, Terraform, Docker

• Strong awareness of security best practices in backend and cloud-native environments

• Understanding of scalable systems and API design

• Experience working in agile, distributed teams

• Fluent English communication

Bonus if you have:

• Experience with AI/ML integration or event-driven systems

• Background in multi-tenant SaaS platforms

Onboarding & Performance Expectations

First 30 Days

• Collaborate with the team to define architecture standards, CI/CD pipelines, and observability tooling

• Develop a functional microservice prototype following agreed design patterns and platform technologies

First 90 Days (to be refined together with the candidate based on strengths)

• Take ownership of migrating one or more critical legacy services to the new architecture

• Share insights, technical recommendations, and improvement ideas

Ongoing Success Metrics

• Will be defined collaboratively with the candidate and reviewed regularly to ensure mutual alignment and growth

Why Join Us

• Work on a greenfield rebuild of a successful international platform

• Take ownership from day one in a flat, transparent environment

• Long-term opportunity with a stable, well-funded product

• Collaborate with an experienced and supportive multinational team

• Opportunity for future relocation to Denmark or other international projects

We Offer

• Exciting projects with Denmark’s most dynamic clients

• Necessary equipment for your work

• For B2B contractors, assistance with maintaining your sole proprietorship (jednoosobowa działalność gospodarcza) in Poland

• Attractive salary package matching experience and responsibilities

• Work out of our centrally located office in Warsaw

• Flexible hybrid work

• 20 days of paid vacation

• Paid sick leave

• Medical insurance

• Local Danish managers offering mentorship and helping you grow communication and interpersonal skills