Senior Java Developer (Backend)

🏢 Summary: Junior Backend Java Developer role focused on building and maintaining scalable backend systems using modern Java and Spring technologies in an international, Agile environment. The position involves developing secure, high-quality applications and collaborating within a hybrid work model. 🗂️ Requirements: Java 17+, Spring / Spring Boot / Spring Security, Maven, SQL, Git (GitHub, CI/CD basics), Experience with unit testing, English B2/C1, Around 2 years of commercial experience, Degree in Computer Science or related field 📃 Skills: Java, Spring, SpringBoot, SpringSecurity, Maven, SQL, Git, GitHub, CICD, UnitTesting 🏢 Description: Junior Backend Java Developer Location: Warsaw, Poland (hybrid – 2 days/week in the office) About the Role We’re looking for a Junior Backend Java Developer to join a team building scalable, modern backend systems for international products. You’ll work in a collaborative environment with a strong focus on learning, ownership, and quality. Responsibilities Develop and maintain backend applications using Java 17+ and Spring Boot Ensure performance, scalability, and security of solutions Work with SQL databases (e.g. PostgreSQL) Support deployments using Docker, Kubernetes, and Helm Use Bash/Shell for automation tasks Collaborate in Agile (Scrum) teams and communicate in English Requirements Java 17+, Spring / Spring Boot / Spring Security Maven, SQL, Git (GitHub, CI/CD basics) Experience with unit testing English B2/C1 Around 2 years of commercial experience Nice to Have PostgreSQL, Hibernate/JPA Kubernetes, Helm Kafka, microservices Bash/Shell or Python CI/CD tools, JIRA Monitoring tools (Grafana, Prometheus) Security basics (OWASP) Qualifications Degree in Computer Science or related field

🏢 Summary: Contract role for a Senior Java Backend Developer to design and build scalable backend systems and microservices for a large enterprise digital platform in a hybrid model in Poland. The position focuses on developing RESTful services, integrating external systems, and optimizing distributed applications. Requires strong experience in Java-based microservices architecture and modern DevOps tools. 🗂️ Requirements: 7+ years of Java development experience, Strong expertise in Java 8+, Experience with Spring and related frameworks, Hands-on microservices development, Experience with RESTful APIs and web services, Experience with Kafka or distributed messaging systems, Understanding of SOA principles, Experience with relational or NoSQL databases, Experience with containerization and orchestration, Knowledge of React or advanced JavaScript, Proficiency with Git, Maven, Jenkins, Registration in Poland as self-employed consultant 📃 Skills: Java, Spring, SpringBoot, SpringMVC, JPA, Hibernate, REST, SOAP, HTTP, JSON, XML, Kafka, SQL, NoSQL, Docker, Git, Maven, Jenkins, React, JavaScript 🏢 Description: Dear Consultant, We are seeking an experienced Senior Java Backend Developer to design and build scalable backend systems and microservices for a large enterprise digital platform. Send CV if you are interested and registered in Poland as a self-employed Consultant. (marcillina.tietjen@dcvtechnologies.co.uk) Senior Java Backend Developer – Microservices (Contract) Location: Gdansk or Warsaw, Poland Work Mode: Hybrid – 1 day onsite per week Seniority: 7+ years experience Key Responsibilities • Design and implement backend systems and microservices• Develop RESTful APIs and web services• Participate in architecture reviews and optimisation initiatives• Debug, profile, and optimise applications• Integrate external APIs and services• Write and maintain technical documentation Required Skills & Experience • Strong expertise in Java 8+ • Frameworks: Spring, Spring Boot, Spring MVC, JPA, Hibernate • Microservices development using HTTP, REST, JSON, XML • Messaging and distributed systems experience ( Kafka ) • Strong understanding of SOA principles and web services (REST & SOAP) • Experience with Relational or NoSQL databases • Exposure to containerisation & orchestration technologies • Experience with React or advanced JavaScript • Tools: Docker, Git, Maven, Jenkins

🏢 Summary: Senior Backend Engineer role focused on designing and developing scalable, reliable backend services using Java. The position involves working in a cross-functional team to build high-performance systems, improve architecture, and support CI/CD and production environments. 🗂️ Requirements: 5+ years Backend Engineering experience, Strong Java proficiency, Solid knowledge of databases and SQL, Experience with RESTful APIs, Experience with microservices architecture, Experience with high-load systems, Experience with Docker and Kubernetes, Experience with AWS or GCP, Knowledge of CI/CD pipelines, Understanding of Agile practices 📃 Skills: Java, SQL, REST, Microservices, Docker, Kubernetes, AWS, GCP, CI/CD, Golang, Python 🏢 Description: We are looking for a Senior Backend Engineer with strong Java experience to help us design and develop scalable solutions. You will work in a cross-functional team, building reliable services and contributing to the continuous improvement of our systems. This role is ideal for someone who enjoys solving complex problems and driving technical excellence. 💼 Responsibilities: Design, develop, and maintain backend features and services. Collaborate with teams to define requirements and integrate systems. Ensure performance, scalability, and reliability of applications. Contribute to CI/CD processes and support production systems. Write clear documentation and share knowledge within the team. ✅ Requirements: 5+ years of experience as a Backend Engineer, with strong Java skills (Golang/Python is a plus). Solid understanding of databases and SQL. Experience with RESTful API design, microservices, and high-load systems. Familiarity with Docker, Kubernetes, and cloud environments (AWS/GCP). Knowledge of CI/CD pipelines and Agile practices. Strong problem-solving and communication skills. 🎁 We offer: Stable employment in a fast-growing company. Flexible and remote-friendly working model. Health and wellbeing benefits. Learning and development opportunities. Modern equipment and comfortable work environment.

🏢 Summary: Senior Java Developer role focused on building, maintaining, and optimizing scalable Java applications for complex financial and enterprise systems in a hybrid Krakow setup. The position involves working with microservices architecture, REST APIs, and databases within an Agile environment. You will contribute to design, development, performance optimization, and technical reviews. 🗂️ Requirements: Minimum 6 years of Java development experience, At least 5 years of experience with Spring and Spring Boot, Strong experience with Microservices architecture, Strong knowledge of REST APIs and integration patterns, Experience with SQL and NoSQL databases, Ability to design application architecture, Experience working in Agile environments 📃 Skills: Java, Spring, SpringBoot, Microservices, REST, SQL, NoSQL, APIs, Architecture, Agile 🏢 Description: 📍 Location: Krakow, hybrid 3 days/week Role: Senior Java Developer Role Description: We are looking for an experienced Java Developer to join technology team. You will be responsible for developing, maintaining, and optimizing Java-based applications that support complex financial systems and enterprise platforms. Key Competencies: Agile way of working and collaboration in cross-functional teams Advanced Java concepts and object-oriented design principles Java API management, RESTful services, and Microservices architecture Database technologies (SQL / NoSQL) and performance optimization Requirements: Minimum 6 years of experience in Java development Strong experience with Spring / Spring Boot and Microservices (5+ years) Good understanding of REST APIs, integration patterns, and application architecture Experience with database technologies and writing efficient queries Ability to work in a team environment and communicate effectively with technical and non-technical stakeholders Experience working in Agile delivery environments Nice-to-Have / Bonus Skills: Experience in production support and troubleshooting Participation in design and architecture reviews Exposure to cloud platforms and modern deployment pipelines Mentoring or leading technical discussions Responsibilities: Design, develop, and maintain scalable Java applications Participate in design and code reviews Troubleshoot issues and optimize system performance Collaborate with business analysts and other teams to deliver solutions Prepare technical documentation and reports as needed

🏢 Summary: Senior Java Spring Boot Backend Developer role focused on building and modernizing a cloud-native Messaging Delivery Platform in the financial sector. The position involves designing and developing scalable microservices, APIs, and distributed systems deployed on Kubernetes and AWS. You will work in an Agile team to deliver secure, high-quality backend solutions for multi-channel customer communication. 🗂️ Requirements: Minimum 6 years of Java development experience, Strong hands-on experience with Spring Boot, Experience designing microservices architectures, Practical experience with Kubernetes, Experience with AWS cloud environments, Proficiency with CI/CD tools (Jenkins, GitHub, Maven, Groovy), Strong knowledge of API design (Swagger, OpenAPI, REST, JSON), Experience with OAuth2 and API Gateway solutions (Kong), Experience with TDD and Scrum methodologies, Legal right to work in the European Union 📃 Skills: Java, Spring, SpringBoot, Microservices, Kubernetes, AWS, Jenkins, GitHub, Maven, Groovy, Swagger, OpenAPI, REST, JSON, OAuth2, Kong, CICD, TDD, Scrum, API 🏢 Description: Unleash innovation at scale — drive the future of cloud-native, microservices architectures! Krakow-based opportunity with hybrid work model (3 remote days per week). As a Senior Java Spring Boot Backend Developer , you will be working for our client in the financial industry, focusing on the Messaging Delivery Platform—centralizing and modernizing message delivery to bank customers across multiple channels. Join a cutting-edge project that shapes the future of client communication through advanced distributed systems and cloud technology. Your main responsibilities: Develop high-quality, scalable backend applications using Java and Spring Boot, ensuring adherence to technical requirements and standards. Collaborate within a multidisciplinary Agile team to design, build, and enhance distributed microservices architectures. Implement and monitor API solutions using Swagger, OpenAPI, REST, and JSON standards, ensuring best practices. Deploy and manage containerized applications on Kubernetes, leveraging AWS cloud infrastructure. Integrate authentication and authorization mechanisms such as OAuth 2 and API Gateway solutions. Write and execute unit tests, contribute to automation testing efforts, and uphold quality benchmarks. Participate in code reviews, challenge implementations to maintain highest quality standards, and promote innovation. Keep abreast of current technologies, tools, and industry best practices, continuously enhancing your expertise. Support and mentor team members to foster a culture of technical excellence and knowledge sharing. You're ideal for this role if you have: Minimum 6 years of experience in Java development within a senior or expert capacity. Strong hands-on expertise with Spring Boot framework and microservices architecture. Practical experience with Kubernetes and Cloud environments, particularly AWS. Proficiency with CI/CD tools such as Jenkins, GitHub, Maven, and Groovy scripting. Deep understanding of API design principles, including Swagger, OpenAPI 3.0, REST, and JSON. Familiarity with authentication protocols like OAuth 2 and API Gateway solutions such as Kong. Robust knowledge of Agile practices, especially TDD and Scrum methodologies. Ability to work fluently in English, with excellent communication skills. It is a strong plus if you have: Certifications or additional experience with AWS services. Knowledge of automation testing frameworks. Experience with messaging systems or middleware. Eligibility for the role: Only candidates with an existing legal right to work in the European Union will be considered for this role. #MAKEYourCareerBETTER Interested? Apply now and include your CV (preferably in English) along with a statement confirming your consent to the processing and storage of your personal data.

🏢 Summary: Long-term B2B contract for a Senior Java Developer to design, build and maintain backend applications and microservices using Spring Boot, with strong focus on system architecture, integrations and cloud environments. The role involves developing REST and asynchronous communication, working with SQL databases, containerization and CI/CD pipelines. Fully remote or hybrid work model available. 🗂️ Requirements: Commercial experience in backend development with Java 11+, Strong knowledge of Java and Spring Framework, Experience in designing and developing microservices, Experience with REST API and asynchronous communication (Kafka, MQ), Practical knowledge of SQL databases (Oracle or PostgreSQL), Experience with Git and CI/CD pipelines, Experience with Docker and Kubernetes, Experience working in Linux environments, Experience with cloud platforms, Ability to write unit and integration tests, Experience working in Agile/Scrum, English proficiency for technical communication 📃 Skills: Java, Spring, SpringBoot, REST, Kafka, MQ, Oracle, PostgreSQL, SQL, Git, CI/CD, Docker, Kubernetes, Linux, Cloud, HTTP, JSON 🏢 Description: Senior Java Developer poszukiwany(-a)! Lokalizacja: 100% zdalnie / hybrydowo (Warszawa/Wrocław/Kraków - do ustalenia) Forma współpracy: B2B Wynagrodzenie (B2B): do 160 zł/h netto + VAT Start: do uzgodnienia Czas trwania projektu: długofalowa współpraca Obowiązki Projektowanie, rozwój i utrzymanie aplikacji backendowych w Javie z wykorzystaniem Spring Framework / Spring Boot Projektowanie i implementacja mikroserwisów oraz komunikacji pomiędzy nimi (REST, integracje asynchroniczne) Tworzenie i utrzymanie szablonów mikroserwisów, bibliotek oraz komponentów platformowych Integracja systemów z wykorzystaniem narzędzi kolejkowych ( Kafka, MQ ) Praca z bazami danych ( Oracle, PostgreSQL ) Udział w projektowaniu architektury systemów oraz doborze technologii Wdrażanie i utrzymanie rozwiązań w różnych środowiskach chmurowych Pisanie testów jednostkowych i integracyjnych , przeprowadzanie code review Monitorowanie i optymalizacja wydajności systemów Tworzenie i promowanie standardów technicznych oraz dobrych praktyk Wsparcie zespołów produktowych (mentoring, przeglądy kodu) Współpraca z zespołami frontend, QA, DevOps Praca w metodyce Agile Wymagania Komercyjne doświadczenie w tworzeniu aplikacji backendowych w Javie (Java 11+) Bardzo dobra znajomość Java oraz Spring Framework / Spring Boot Doświadczenie w projektowaniu i rozwoju mikroserwisów Znajomość REST API , HTTP/JSON oraz komunikacji asynchronicznej ( Kafka, MQ ) Praktyczna znajomość baz danych SQL (np. Oracle, PostgreSQL), mile widziane NoSQL Doświadczenie z Git , CI/CD oraz narzędziami developerskimi Znajomość Docker i Kubernetes oraz pracy w środowisku Linux Doświadczenie w pracy z platformami chmurowymi Umiejętność tworzenia wydajnych i jakościowych rozwiązań , dbałość o standardy kodu Doświadczenie w pracy w metodykach Agile / Scrum Samodzielność, dobra organizacja pracy i umiejętności komunikacyjne Znajomość języka angielskiego na poziomie umożliwiającym swobodną komunikację Mile widziane: doświadczenie z technologiami front-end, np. Angular, React Nie zwlekaj i zaaplikuj już teraz! Nr ref.: 58/12/2025/MB/2997

🏢 Summary: Senior Java Developer role focused on designing and owning mission-critical backend systems in fintech and high-scale environments. The position involves leading microservices architecture, optimizing performance and reliability, and mentoring engineers. Full-time onsite work in Warsaw with strong emphasis on architectural quality and production-grade systems. 🗂️ Requirements: Full-time onsite availability in Warsaw, 5+ years commercial experience in Java development, Strong commercial experience with Java and Spring (Boot, Security, Data), Deep knowledge of Hibernate ORM and SQL databases, Strong understanding of JVM internals, Experience designing scalable backend architectures, Proficiency with CI/CD pipelines, Proficiency with Git, Proficiency with Gradle, Experience with production debugging, Ability to use AI-assisted development tools, English level B2 or higher 📃 Skills: Java, Spring, SpringBoot, SpringSecurity, SpringData, Hibernate, SQL, JVM, PostgreSQL, CI/CD, Git, Gradle, REST, SOLID, DDD, ChatGPT, Claude, Cursor, Grok 🏢 Description: 📍 Warsaw (Onsite – near Metro Plac Wilsona) 💼 B2B / Freelance About Silk Software House Silk Software House builds and maintains mission-critical backend systems for fintech, payments, and large-scale platforms. We value strong engineering judgment, ownership, and long-term cooperation over short-term delivery pressure. Your Role As a Senior Java Developer, you’ll take technical ownership of backend services, influence architectural decisions, and mentor other engineers. You’ll work directly on complex domains where performance, security, and reliability matter. Responsibilities Design and implement backend architectures using Java 11+ and Spring Lead development of microservices and APIs Optimize performance, scalability, and data consistency Work deeply with Hibernate , transactions, and database internals Review code, mentor developers, and set engineering standards Collaborate with DevOps on deployments and observability Requirements This role requires full-time onsite work (no remote or hybrid options). Candidates must be willing and able to work from our office near the Plac Wilsona metro station 5+ years of commercial experience as a Java Developer Strong commercial experience with Java & Spring (Boot, Security, Data) Deep knowledge of Hibernate ORM , SQL databases, and JVM behavior Experience designing scalable, maintainable backend architectures Proficiency with CI/CD, Git, Gradle, and production debugging Effective use of AI-assisted development tools ( ChatGPT, Claude, Cursor, Grok ) English at B2+ level Nice to Have Event-driven architecture (Kafka, queues) Cloud-native systems (AWS/GCP/Azure) Kubernetes, Docker, observability tools Experience in fintech or high-traffic systems Rates (B2B) 120–160 PLN / hour Recruitment Process Intro call (30 min) Senior-level technical interview Architecture & project discussion Offer Tech Stack Java: Advanced Spring Boot: Advanced Hibernate: Advanced PostgreSQL: Advanced Solid: Advanced DDD: Advanced REST API: Advanced

🏢 Summary: Senior Java Developer role focused on designing and owning high-performance backend systems for fintech and large-scale platforms. The position involves leading microservices architecture, optimizing performance and data consistency, and mentoring engineers in a full-time onsite setup in Warsaw. Strong emphasis on architectural decision-making, security, and reliability in production environments. 🗂️ Requirements: 5+ years commercial experience as Java Developer, Strong commercial experience with Java and Spring (Boot, Security, Data), Deep knowledge of Hibernate ORM and SQL databases, Strong understanding of JVM behavior, Experience designing scalable backend architectures, Proficiency with CI/CD pipelines, Proficiency with Git and Gradle, Experience with production debugging, Ability to work full-time onsite in Warsaw, Effective use of AI-assisted development tools (ChatGPT, Claude, Cursor, Grok), English level B2+ or higher 📃 Skills: Java, Spring, SpringBoot, SpringSecurity, SpringData, Hibernate, SQL, PostgreSQL, JVM, CI/CD, Git, Gradle, REST, SOLID, DDD, ChatGPT, Claude, Cursor, Grok 🏢 Description: 📍 Warsaw (Onsite – near Metro Plac Wilsona) 💼 B2B / Freelance About Silk Software House Silk Software House builds and maintains mission-critical backend systems for fintech, payments, and large-scale platforms. We value strong engineering judgment, ownership, and long-term cooperation over short-term delivery pressure. Your Role As a Senior Java Developer, you’ll take technical ownership of backend services, influence architectural decisions, and mentor other engineers. You’ll work directly on complex domains where performance, security, and reliability matter. Responsibilities Design and implement backend architectures using Java 11+ and Spring Lead development of microservices and APIs Optimize performance, scalability, and data consistency Work deeply with Hibernate , transactions, and database internals Review code, mentor developers, and set engineering standards Collaborate with DevOps on deployments and observability Requirements This role requires full-time onsite work (no remote or hybrid options). Candidates must be willing and able to work from our office near the Plac Wilsona metro station 5+ years of commercial experience as a Java Developer Strong commercial experience with Java & Spring (Boot, Security, Data) Deep knowledge of Hibernate ORM , SQL databases, and JVM behavior Experience designing scalable, maintainable backend architectures Proficiency with CI/CD, Git, Gradle, and production debugging Effective use of AI-assisted development tools ( ChatGPT, Claude, Cursor, Grok ) English at B2+ level Nice to Have Event-driven architecture (Kafka, queues) Cloud-native systems (AWS/GCP/Azure) Kubernetes, Docker, observability tools Experience in fintech or high-traffic systems Rates (B2B) 120–160 PLN / hour Recruitment Process Intro call (30 min) Senior-level technical interview Architecture & project discussion Offer Tech Stack Java: Advanced Spring Boot: Advanced Hibernate: Advanced PostgreSQL: Advanced Solid: Advanced DDD: Advanced REST API: Advanced

🏢 Summary: Role for a Mid+/Senior Java Backend Developer focused on designing and building scalable backend systems and REST APIs in a microservices architecture. The position involves architectural decisions, code quality ownership, and collaboration in an international Agile environment. Opportunity to impact global digital products and engineering standards. 🗂️ Requirements: 6+ years experience as Java Developer, Strong knowledge of Java, Experience building REST APIs, Experience with microservices architecture, Knowledge of relational or NoSQL databases, Experience with cloud platforms (GCP preferred), Experience with Docker and Kubernetes, Knowledge of design patterns, Experience with unit and integration testing, Experience working in Agile methodologies, Very good English skills 📃 Skills: Java, REST, Microservices, PostgreSQL, MySQL, MongoDB, GCP, Docker, Kubernetes, JUnit, Agile 🏢 Description: Dołącz do międzynarodowego zespołu technologicznego pracującego nad rozwojem nowoczesnych produktów cyfrowych, które mają realny wpływ na globalny biznes i procesy operacyjne. Szukamy doświadczonego Java Developera (Backend) który chce budować skalowalne systemy i mieć wpływ na architekturę oraz standardy technologiczne. Stanowisko: Java Developer (Mid+/Senior). Lokalizacja biura: Warszawa. 🛠 Stack technologiczny: Java, Microservices, REST API, Docker, Kubernetes, GCP, PostgreSQL, MySQL, MongoDB. Osoba na tym stanowisku będzie odpowiedzialna za projektowanie, rozwój i utrzymanie wydajnych oraz skalowalnych systemów backendowych. Będzie współpracować z zespołami produktowymi i technologicznymi w środowisku międzynarodowym oraz mieć realny wpływ na kierunek rozwoju rozwiązań. Zadania: Projektowanie i rozwój backendu oraz API (REST) Tworzenie skalowalnych mikroserwisów Dbanie o jakość kodu (code review, testy, dobre praktyki) Współpraca z frontendem, Product Ownerem i innymi interesariuszami Rozwiązywanie problemów produkcyjnych i optymalizacja systemów Wdrażanie i promowanie dobrych praktyk inżynierskich Mentoring mniej doświadczonych developerów Udział w decyzjach architektonicznych Wymagania: Ponad 6 lat doświadczenia jako Java Developer Bardzo dobra znajomość Java Doświadczenie w budowie REST API i mikroserwisów Znajomość baz danych (np. PostgreSQL, MySQL, MongoDB) Doświadczenie z chmurą (preferowana GCP ) Znajomość Dockera i Kubernetes Znajomość wzorców projektowych i dobrych praktyk Doświadczenie w testowaniu (unit/integration) Praca w metodykach Agile Bardzo dobra znajomość języka angielskiego Mile widziane: Znajomość: .NET / Python / Node.js Firma oferuje: Udział w projektach o globalnym zasięgu i realnym wpływie na biznes Pracę w doświadczonym, międzynarodowym zespole Możliwość wpływu na architekturę i standardy technologiczne Hybrydowy model pracy (2 dni w tygodniu praca z biura) Stabilne zatrudnienie i atrakcyjny pakiet benefitów Możliwość rozwoju technicznego i mentoringowego

🏢 Summary: Senior Java Developer role focused on building and optimizing high-throughput, event-driven backend microservices in a distributed architecture based on Kafka. The position involves designing scalable and reliable systems using modern Java and Spring Boot within an agile, international environment. Work includes performance optimization, asynchronous communication, and implementation of DDD and Event Sourcing patterns. 🗂️ Requirements: 5+ years of Java backend development experience, Strong hands-on experience with Kafka producer/consumer design and optimization, Experience with SQL and relational databases (Oracle, DB2, MSSQL or similar), Experience building distributed, high-availability, high-performance systems, Practical knowledge of Domain-Driven Design (DDD) and Event Sourcing, Experience with microservices architecture, Fluent English 📃 Skills: Java, Spring, Kafka, SQL, Oracle, DB2, MSSQL, Docker, Git, Maven, Microservices, CI/CD, DDD, EventSourcing, Splunk, Grafana 🏢 Description: We’re looking for a Senior Java Developer to support the development of business-critical backend services in a distributed, high-throughput architecture. The system is built on Kafka-based asynchronous communication and designed with a strong focus on performance, scalability, and reliability. You will be involved in designing and developing clean, event-driven microservices, working closely with experienced engineers in an international, agile setup. Tech stack Java 11+, Spring Boot Apache Kafka – producer/consumer optimization, retries, partitioning SQL: Oracle / DB2 / MSSQL Docker, Git, Maven Microservices architecture CI/CD pipelines Domain-Driven Design (DDD), Event Sourcing Monitoring: Splunk / Grafana (nice to have) What we expect 5+ years of experience in Java backend development Strong hands-on skills in Kafka producer/consumer design and optimization Solid experience in SQL and relational databases (Oracle, DB2, MSSQL or similar) Proven background in building distributed, high-availability, high-performance systems Practical understanding of DDD, Event Sourcing, microservices, and clean architecture Fluent English for daily collaboration