Principal Java Developer
., Poland (Remote)
DCG
As a recruitment company, DCG understands that every business is powered by experienced professionals. Our management style and partnership approach enable us to meet your needs and provide continuous support. Due to our ongoing growth and the large number of recruitment projects we undertake for our partners, we are currently looking for:
Principal Java Developer
Responsibilities:
Lead end-to-end development with Java (Quarkus/Spring) backend and React/TypeScript frontend, ensuring architectural consistency
Drive adoption of AI-assisted tools like Claude Code, guide prompt engineering, review AI-generated code, and integrate AI securely
Architect and implement scalable Java microservices and APIs with maintainable, testable code
Design and optimize MongoDB and PostgreSQL databases including schema, indexing, data modeling, queries, and migrations
Build event-driven systems with Kafka, implement event sourcing, reliable messaging, and integrate with ELK monitoring
Identify and resolve performance bottlenecks across frontend, backend, and databases, applying monitoring and optimization strategies
Maintain CI/CD pipelines in Jenkins, integrate SonarQube, Snyk, OWASP, manage Nexus repositories, automate deployments, IaC, and container orchestration
Define comprehensive testing strategies: unit, integration, end-to-end, performance, and security testing
Ensure full-stack security: secure coding, authentication/authorization, vulnerability and secrets management, compliance
Provide technical leadership, mentorship, code reviews, set standards, and make key architectural decisions
Integrate AI/ML services, LLM APIs, and intelligent automation, applying responsible AI practices
Collaborate with product, architecture, security, and business teams to translate requirements into technical solutions
Take full ownership of features and systems from design to deployment and maintenance
Requirements:
10+ years in software development, including 3–5 years in senior/principal roles with technical leadership
8+ years Java (Quarkus/Spring Boot) with Maven/Gradle, JVM internals, performance tuning, and scalable enterprise apps
Full-stack expertise with React, TypeScript/JavaScript (ES6+), HTML5, CSS3, responsive design, Redux/Context API, and frontend optimization
Advanced MongoDB and PostgreSQL skills, including queries, indexing, replication, sharding, migrations, and data modeling
Experience with Kafka event-driven architectures and monitoring tools (ELK, Prometheus, Grafana)
DevOps and CI/CD skills with Docker, Kubernetes, Jenkins, SonarQube, Nexus, GitOps, Terraform/Ansible, and container orchestration
Experience with AI-assisted development (Claude Code, GitHub Copilot), LLM APIs, prompt engineering, and AI/ML frameworks
Strong testing skills: JUnit, Mockito, Testcontainers, Jest, React Testing Library, Selenium/Cypress, JMeter, Gatling
Security expertise: secure coding, OAuth2/JWT/OIDC, vulnerability management, and compliance
Performance engineering with profiling tools (JProfiler, VisualVM, Chrome DevTools) and APMs (New Relic, Dynatrace, AppDynamics)
Agile/Scrum experience, mentoring, technical decision-making, and process improvement
Strong communication, collaboration, and end-to-end ownership of initiatives
Passion for emerging technologies, AI-assisted development, and innovation
Nice to have:
Experience with additional frontend frameworks (Vue.js, Angular)
Knowledge of GraphQL and API design patterns
Familiarity with observability platforms and distributed tracing
Experience in the aviation or air traffic management domain
Understanding of AIXM (Aeronautical Information Exchange Model) or aeronautical data standards
Contributions to open-source projects or technical community engagement
Certifications in relevant technologies (AWS, Kubernetes, Java, etc.)
Offer:
Private medical care
Co-financing for the sports card
Constant support of dedicated consultant
Employee referral program

DCG to przestrzeń, w której spotykają się potrzeby biznesu i ambicje ludzi. Znamy wartość dobrze dopasowanej współpracy, dlatego pomagamy kandydatom znaleźć środowisko, w którym będą mogli rozwinąć skrzydła, a firmom - z...
Principal Java Developer
Principal Java Developer
., Poland (Remote)
DCG