Senior Java Developer

🏢 Summary: Senior Java Developer role focused on building and optimizing scalable backend systems for real-time data processing in a fully remote environment. The position involves developing Java 17+ and Spring Boot applications, managing Kafka streams, implementing CI/CD pipelines, and maintaining high-quality testing and database solutions. 🗂️ Requirements: 5+ years of Java development experience, Java 17+ proficiency, Spring Boot expertise, REST API design experience, Apache Kafka experience, JUnit knowledge, Mockito knowledge, CI/CD experience, Jenkins familiarity or GitLab CI familiarity, Good Polish language skills, Communicative English level, Legal right to work in the European Union 📃 Skills: Java, Spring, Kafka, JUnit, Mockito, REST, Jenkins, GitLab, PostgreSQL, RabbitMQ, OpenShift, Prometheus, Grafana, JMeter 🏢 Description: Unleash innovative backend solutions — shape the future of real-time data processing! 100% remote work. As a Senior Java Developer, you will be working for a client focused on building robust, scalable software solutions. You will contribute to advancing data-driven platforms, delivering impactful backend components that support critical business operations and digital transformation. Your main responsibilities: - Develop and optimize Java 17+ applications with Spring Boot, focusing on REST API creation and integration. - Design and write automated tests, including unit, integration, contract, and API testing using JUnit, Mockito, and REST Assured. - Manage Apache Kafka streams, ensuring seamless real-time data processing and system reliability. - Implement CI/CD pipelines with Jenkins or GitLab CI to improve development workflows. - Maintain and enhance PostgreSQL database solutions, ensuring data integrity and performance. - Collaborate across teams to troubleshoot and resolve complex technical issues. - Document technical specifications and participate in code reviews. You’re ideal for this role if you have: - At least 5 years of professional experience in Java development. - Advanced knowledge of Java 17+, Spring Boot, and REST API design. - Proven expertise with Apache Kafka. - Experience with testing frameworks such as JUnit and Mockito. - Familiarity with CI/CD tools like Jenkins or GitLab CI. Nice to have: - Working knowledge of PostgreSQL and RabbitMQ. - Experience with OpenShift, Prometheus, Grafana, or JMeter. Language requirements: - Polish: Good command. - English: Communicative level. Eligibility: - Only candidates with an existing legal right to work in the European Union will be considered. Interested candidates should apply with a CV, preferably in English, including consent to the processing and storage of personal data.

🏢 Summary: Senior Java Developer role focused on designing and implementing enterprise-grade backend solutions using modern architecture principles. The position emphasizes high code quality, performance, security, and collaboration within a distributed team. The role involves working with Java 17+, Spring ecosystem, databases, and event-driven systems. 🗂️ Requirements: Minimum 5 years of commercial software development experience, Very good knowledge of Java 17+, Strong understanding of object-oriented design patterns, Experience with Spring MVC and Spring Data, Experience with Apache Kafka, Ability to design relational and non-relational databases (MS SQL, Oracle, Elasticsearch, Redis), Knowledge of software engineering best practices, English proficiency for technical documentation, Ability to work effectively in a distributed team 📃 Skills: Java, Spring, SpringMVC, SpringData, Kafka, MSSQL, Oracle, Elasticsearch, Redis, OOP, UML, Docker, Kubernetes, Azure, JavaScript, React, Python 🏢 Description: We are looking for an experienced Senior Java Developer with at least 5 years of commercial experience to join a team working on enterprise-grade backend solutions. The role focuses on designing and implementing software in a modern architecture, with a strong emphasis on code quality, performance, security, and effective collaboration within a distributed team. Responsibilities Design and implement software using hexagonal architecture. Develop backend solutions using Java 17+ and the Spring ecosystem. Ensure high code quality and compliance with agreed development standards. Analyse system performance, security, and stability, and propose improvements. Design and optimise data structures for relational and non-relational databases. Collaborate with a distributed team, participate in technical analysis, code reviews, and solution design. Identify technical challenges and propose improvements to architecture and implementation. Requirements Minimum 5 years of commercial software development experience. Very good knowledge of Java 17+. Strong understanding of object-oriented design patterns and software engineering best practices. Experience with the Spring stack, especially Spring MVC and Spring Data. Knowledge of Apache Kafka. Ability to design databases: relational: MS SQL, Oracle, non-relational: Elasticsearch, Redis. English skills sufficient to work with technical documentation. Strong analytical and creative problem-solving skills. Excellent communication skills and ability to work effectively in a distributed team. Nice to have Knowledge of scripting/frontend technologies such as JavaScript, React, Python. Experience working in an Azure cloud environment. Familiarity with Kubernetes and Docker. Ability to design system architecture and prepare High-Level Design (HLD) documentation. Knowledge of UML and flow diagrams.

🏢 Summary: Senior Backend Java Developer role focused on designing and building scalable, high-performance backend systems using Java and Spring Boot in a cloud-native environment. The position involves developing enterprise-grade solutions, ensuring performance and security, and supporting containerized deployments. The role requires strong experience with modern backend technologies and infrastructure tools. 🗂️ Requirements: 8+ years of backend development experience, Strong experience with Java 17+, Strong experience with Spring and Spring Boot, Experience with Spring Security, Experience with SQL databases, Experience with Maven, Experience with Git and CI/CD pipelines, Experience with testing frameworks (JUnit, AssertJ, Hamcrest), Experience with Kubernetes and Helm, Experience with Bash or Shell scripting, Experience with cloud-native applications, Experience in enterprise environments 📃 Skills: Java, Spring, SpringBoot, SpringSecurity, SQL, Maven, Git, CICD, JUnit, AssertJ, Hamcrest, Kubernetes, Helm, Bash, Shell, Docker, PostgreSQL 🏢 Description: Senior Backend Java Developer Location: Warsaw, Poland (hybrid – 2 days/week in the office) About the Role We’re looking for a Senior Backend Java Developer to design and build scalable, high-performance backend systems for international products. You’ll work in a collaborative environment, contribute to architectural decisions, and mentor other engineers. Responsibilities Design, develop, and maintain backend systems using Java 17+ and Spring Boot Ensure scalability, performance, and security of solutions Work with SQL databases (e.g. PostgreSQL) Support deployments using Docker, Kubernetes, and Helm Use Bash/Shell for automation and integration tasks Lead technical discussions and mentor team members Collaborate in Agile (Scrum) teams and communicate in English Requirements Strong experience with Java 17+, Spring / Spring Boot / Spring Security Experience with cloud-native applications Maven, SQL, Git (GitHub, CI/CD) Testing frameworks (JUnit, AssertJ, Hamcrest) Kubernetes, Helm Bash/Shell scripting English B2/C1 Experience in enterprise environments 8+ years of backend development experience Nice to Have PostgreSQL, Hibernate/JPA Kafka, event-driven architecture Microservices architecture Python Knowledge of C or Go CI/CD tools, JIRA Monitoring tools (Grafana, Prometheus, Kibana) Security best practices (OWASP) Qualifications Degree in Computer Science or related field

🏢 Summary: Senior Java Developer role focused on designing and building high-performance, scalable backend systems in a distributed microservices environment for the financial sector. The position involves developing REST APIs, processing large data volumes, and contributing to architecture and CI/CD in cloud-based environments. The role requires strong expertise in Java, Spring, distributed systems, and Kubernetes. 🗂️ Requirements: Minimum 10 years of software development experience, Very good knowledge of Java and Spring, Strong understanding of REST APIs, HTTPS, microservices, and message queues, Ability to design high-availability, scalable, high-performance systems, Very good knowledge of relational databases and SQL, Knowledge of distributed systems and data processing, Hands-on experience with Kubernetes and cloud platforms (GCP preferred), Familiarity with CI/CD pipelines, Experience working in Agile methodologies, Fluent Polish and English, Residence in Poland 📃 Skills: Java, Spring, REST, HTTPS, Microservices, MQ, SQL, Kubernetes, GCP, CI/CD, Agile, DistributedSystems, DataProcessing 🏢 Description: We are looking for an experienced Senior Java Developer to join a team responsible for building and developing modern backend systems in a distributed environment. The projects involve high-performance and scalable solutions used in the financial sector, with a focus on processing large volumes of data and microservices architecture. Your tasks Designing and developing backend systems based on Java Creating and evolving a microservices architecture Building and maintaining REST APIs and system integrations Designing solutions that meet high availability and performance requirements Working with systems that process large volumes of data Collaborating with the team using Agile methodologies Participating in architecture design and technical decision-making Implementing and optimizing CI/CD processes and ensuring system security Requirements Minimum 10 years in software development Very good knowledge of Java (backend) and Spring Strong understanding of REST APIs, HTTPS, microservices, and message queues (MQ) Ability to design high-availability, scalable, and high-performance systems Very good knowledge of relational databases (SQL) Familiarity with CI/CD pipelines and Agile ways of working Knowledge of distributed systems and data processing Hands-on work with Kubernetes and cloud platforms (GCP preferred) Fluent Polish and English required Residing in Poland required Nice-to-have requirements Knowledge of Go, Rust, or similar system-level languages Experience with NoSQL and analytical databases, e.g., ClickHouse Frontend development experience Familiarity with the banking sector (trade lifecycle, FX, post-trade processing) Banking experience / FX experience (forex) Working from the office in Krakow 6 times per month What we offer Great Place to Work since 2015 - it’s thanks to feedback from our workers that we get this special title and constantly implement new ideas Employment stability - revenue of PLN 2.1BN, no debts, since 2006 on the market We share the profit with Workers - over PLN 76M has already been allocated for this aim since 2022 Attractive benefits package - private healthcare, benefits cafeteria platform, car discounts and more Comfortable workplace – class A offices or remote work Dozens of fascinating projects for prestigious brands from all over the world PLN 1 000 000 per year for your ideas - with this amount, we support the passions and voluntary actions of our workers Investment in your growth – meetups, webinars, training platform and technology blog – you choose Fantastic atmosphere created by all Sii Power People If you want to work on systems with high operational significance — apply now!

🏢 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 Engineer role focused on building a greenfield distributed backend platform in a manufacturing environment using microservices and event-driven architecture. The position involves developing scalable backend services, APIs, integrations, and contributing to system design for complex enterprise data flows. Candidates will work on performance, scalability, and reliability challenges in a high-tech production domain. 🗂️ Requirements: 5+ years in Java backend development, Strong understanding of backend systems and microservices, Experience with REST APIs and distributed systems, Knowledge of concurrency and scalable system design, Solid SQL and database design skills, Experience with system integrations, Ability to work in fast-moving, ambiguous environments 📃 Skills: Java, Microservices, REST, SQL, APIs, Concurrency, ETL, ERP, IoT, MES 🏢 Description: We are looking for a Senior Java Engineer to join a greenfield distributed backend platform within a complex manufacturing environment. The role involves building backend services , APIs , and integrations in an event-driven architecture with a strong focus on scalability , system design , and distributed systems challenges. ✅ Your responsibilities: Develop backend services within a microservices architecture Build and maintain APIs and system integrations Implement workflow, event processing, and data-driven components Contribute to system design and architecture decisions Optimize for performance, scalability, and reliability Work with complex production and enterprise data flows 🧠 Our requirements: 5+ years in Java backend development Strong understanding of backend systems and microservices Experience with REST APIs and distributed systems Knowledge of concurrency and scalable system design Solid SQL and database design skills Experience with system integrations Ability to work in fast-moving, ambiguous environments ⭐ Nice to have: Exposure to manufacturing / MES / IoT systems Experience with event-driven architecture Familiarity with ETL / data pipelines Experience integrating ERP / enterprise systems 🌟 What we offer: Private healthcare Multisport Life insurance Opportunity to build a greenfield distributed platform from scratch Real influence on architecture and technical direction Work in a high-tech manufacturing domain (photonics / hardware systems) Collaboration with experienced system engineers

🏢 Summary: Senior Java Engineer role focused on building a greenfield distributed backend platform in a complex manufacturing environment. The position involves developing microservices, APIs, and integrations within an event-driven architecture, with strong emphasis on scalability, performance, and system design. The engineer will contribute to architectural decisions and work with complex enterprise data flows. 🗂️ Requirements: 5+ years of Java backend development experience, Strong knowledge of backend systems and microservices, Experience with REST APIs, Experience with distributed systems, Understanding of concurrency, Scalable system design knowledge, Solid SQL skills, Database design skills, Experience with system integrations, Ability to work in fast-moving, ambiguous environments 📃 Skills: Java, REST, SQL, Microservices, DistributedSystems, Concurrency, ETL, ERP, MES, IoT 🏢 Description: We are looking for a Senior Java Engineer to join a greenfield distributed backend platform within a complex manufacturing environment. The role involves building backend services , APIs , and integrations in an event-driven architecture with a strong focus on scalability , system design , and distributed systems challenges. ✅ Your responsibilities: Develop backend services within a microservices architecture Build and maintain APIs and system integrations Implement workflow, event processing, and data-driven components Contribute to system design and architecture decisions Optimize for performance, scalability, and reliability Work with complex production and enterprise data flows 🧠 Our requirements: 5+ years in Java backend development Strong understanding of backend systems and microservices Experience with REST APIs and distributed systems Knowledge of concurrency and scalable system design Solid SQL and database design skills Experience with system integrations Ability to work in fast-moving, ambiguous environments ⭐ Nice to have: Exposure to manufacturing / MES / IoT systems Experience with event-driven architecture Familiarity with ETL / data pipelines Experience integrating ERP / enterprise systems 🌟 What we offer: Private healthcare Multisport Life insurance Opportunity to build a greenfield distributed platform from scratch Real influence on architecture and technical direction Work in a high-tech manufacturing domain (photonics / hardware systems) Collaboration with experienced system engineers

🏢 Summary: Senior Java Developer role focused on designing, building, and maintaining scalable, secure, high-performance backend systems using modern Java and cloud-native technologies. The position involves working in Agile teams, leading technical discussions, mentoring developers, and driving DevOps automation. Hybrid work model with regular presence in the Warsaw office. 🗂️ Requirements: 8+ years of backend development experience, Proficiency in Java 17+, Experience with Spring Boot and Spring Security, Strong knowledge of Hibernate and JPA, Experience with Maven, Strong SQL skills with PostgreSQL, Experience in cloud-native application development, Hands-on experience with Git and GitHub pipelines, Experience with CI/CD tools, Experience with Kubernetes and Helm, Ability to write Bash/Shell scripts, Experience with JUnit, AssertJ, and Hamcrest, Degree in Computer Science or equivalent experience 📃 Skills: Java, Spring, SpringSecurity, Hibernate, JPA, Maven, PostgreSQL, SQL, Kubernetes, Helm, Docker, Bash, Git, GitHub, CICD, JUnit, AssertJ, Hamcrest 🏢 Description: Role Overview As a Senior Java Developer, you will design, build, and maintain scalable, secure, and high-performance backend systems. Working closely with cross-functional teams, you’ll drive innovation – including the use of GenAI tools like GitHub Copilot -and mentor other developers. Work mode: hybrid 2-3 days / 5 days at the Warsaw office. Key Responsibilities Backend & DB: Develop robust, multi-tenant applications using Java 17+, Spring Boot, and PostgreSQL. DevOps & Automation: Manage deployments using Docker, Kubernetes, and Helm; automate tasks via Bash/Shell scripting. Leadership & Agile: Lead design discussions, mentor peers, and actively participate in Scrum events within a distributed team. Requirements Technical Skills: Java Stack: Java 17+, Spring (Boot, Security), Hibernate/JPA, Maven. Data & Cloud: SQL (PostgreSQL), cloud-native application development. DevOps & CI/CD: Git/GitHub (pipelines), CI/CD tools, Kubernetes, Helm, Bash. Testing: JUnit, AssertJ, Hamcrest. Skills & Experience: 8+ years of professional backend experience (preferably in enterprise environments). Degree in Computer Science (or equivalent experience). Fluent English ( B2/C1 ) and strong collaboration skills in Agile teams. Nice-to-Have Kafka & Event-driven / Microservices architecture. Python, C, or Go (Golang) scripting. Monitoring tools (Kibana, Grafana, Prometheus). Security best practices (OWASP Top 10) & Jira. Client A global leader with a sharp focus on lottery solutions. A confident step forward building on a long history of delivering safe and secure technology, demonstrating strong commitment to customers as a dedicated lottery service provider. Leveraging collective insight, experience, and expertise to create reliable and engaging solutions that help lottery clients achieve objectives, meet player needs, and deliver meaningful benefits to communities.

🏢 Summary: Senior Java Developer role in an agile, international team focused on designing and building cloud-based backend and fullstack solutions. The position involves architecting scalable systems, ensuring high code quality, and contributing to CI/CD and DevOps practices. The role also includes technical leadership and collaboration with cross-functional teams to deliver secure, high-performance applications. 🗂️ Requirements: Expert knowledge of Java for backend and fullstack development, Experience architecting cloud-based SaaS solutions, Proficiency in automated testing and CI/CD pipelines, Experience with version control systems, Ability to deliver secure and scalable code, Bachelor’s degree in Computer Science, Engineering or related field with 5+ years of experience OR 9+ years of relevant industry experience 📃 Skills: Java, SaaS, CI/CD, Git, AWS, GCP, Azure, Docker, Kubernetes, TypeScript, Python 🏢 Description: About the Role: We are looking for a Senior Java Developer to join an agile, international engineering team working on cloud-based solutions serving diverse industries. As a technical leader, you will design, build, and maintain robust backend and fullstack systems, impacting both product performance and business outcomes. Must Have Expert knowledge of Java (backend/fullstack web development) Experience architecting cloud-based solutions (SaaS platforms or similar) Proficiency in automated testing, deployment pipelines, version control, and CI/CD practices Strong command of English for daily teamwork in multicultural environments Demonstrated ability to deliver secure, scalable, high-quality code Bachelor’s degree in Computer Science, Engineering, or related field with 5+ years of professional experience, OR 9+ years’ relevant industry experience (without degree) Nice to Have Exposure to other technologies (TypeScript, Python, etc.) Experience working with multiple data models and integrating acquired codebases Previous engagement in Agile/Scrum teams (sprint planning, retrospectives, hackathons) Background in industries like energy, IoT, finance, or regulated environments Familiarity with modern cloud platforms (AWS, GCP, Azure) and DevOps practices (Docker, Kubernetes) Your Profile Tech Enthusiast: Keen to learn and apply emerging technologies and best practices Analytical Thinker: Able to define requirements and design effective solutions to complex challenges Product Mindset: Understands how technical decisions influence user experience and business drivers Team Player: Works well in autonomous, distributed teams and supports collaborative engineering culture Key Responsibilities Design and develop Java-based backend and fullstack features for cloud-based applications Contribute to scalable, unified system architectures and help integrate diverse platforms and technologies Write and maintain high-performance, secure code and automated tests to ensure product quality Participate in sprint planning, code reviews, retrospectives, and technical discussions Work closely with product managers and business stakeholders to align technical development with commercial goals Mentor junior engineers and promote continuous improvement in team processes Ready for your next challenge? Send your CV detailing your experience in Java, cloud technologies, and agile teams. Tell us about your approach to system architecture and cross-team collaboration!

🏢 Summary: Full-time Senior Java Developer role focused on designing and maintaining high-performance, secure backend systems in a cloud-native environment. The position involves leading technical design, developing scalable applications with Java 17+ and Spring Boot, and supporting CI/CD and Kubernetes-based deployments. Work is remote or hybrid (Warsaw) within Agile, distributed teams. 🗂️ Requirements: Mastery of Java 17+, Proficiency in Spring, Spring Boot, Spring Security, Experience in cloud-native application development, Experience with Maven, Experience with SQL databases, Proficiency in Git and GitHub including pipeline development, Knowledge of JUnit, AssertJ, Hamcrest, Experience with CI/CD tools and processes, Experience with Kubernetes and Helm, Bash/Shell scripting skills, Experience in enterprise environments, Experience working in Agile (Scrum/Kanban) teams 📃 Skills: Java, Spring, SpringBoot, SpringSecurity, Maven, SQL, Git, GitHub, JUnit, AssertJ, Hamcrest, CICD, Kubernetes, Helm, Bash, Shell, Docker 🏢 Description: Type of work : Full-time; Remote/Hybrid (Warsaw) As a Senior Java Developer, you will lead the design, development, and maintenance of high-performance backend systems. You’ll collaborate with product managers, architects, and developers to ensure our solutions are scalable, secure, and future-ready. We encourage the use of Generative AI tools like GitHub Copilot to boost innovation and productivity. Requirements Java, Postgresql, Liquibase, Spring boot, Angular. Responsibilities Develop robust, configurable applications using Java 17+ and Spring Boot to effectively meet the diverse requirements of multiple customers. Ensure the efficiency of PostgreSQL databases for scalable solutions. Ensure security, scalability, and performance in all backend solutions. Employ Bash/Shell scripting for automation and comprehensive system integration tasks. Contribute to application deployment using Docker and Kubernetes , while utilizing Helm for package management. Communicate effectively in English (B2/C1 level) within distributed teams. Participate actively in scrum events. Collaborate with other engineering teams. Lead design discussions and mentor other developers. Client A global leader with a sharp focus on lottery solutions. A confident step forward building on a long history of delivering safe and secure technology, demonstrating strong commitment to customers as a dedicated lottery service provider. Leveraging collective insight, experience, and expertise to create reliable and engaging solutions that help lottery clients achieve objectives, meet player needs, and deliver meaningful benefits to communities.