Java Technical Specialist

🏢 Summary: Senior Java Developer role focused on developing, maintaining, and modernizing employee-facing platforms in a complex enterprise environment within the financial sector. The position involves working with both modern and legacy technologies, operational support, troubleshooting, and ensuring platform stability for approximately 9,000 daily users. 🗂️ Requirements: 5+ years of Java development experience, Experience in complex enterprise environments, Ability to work with modern and legacy solutions, Collaborative mindset, Pragmatic approach to problem solving 📃 Skills: Java, WebSphere, Tomcat, JBoss 🏢 Description: On behalf of a client in the financial sector, we are looking for a Senior Java Developer. The consultant will join the team responsible for developing and maintaining employee-facing platforms. The team comprises software developers, a Product Owner, an IT architect, and a manager, collectively supporting approximately 9,000 employees. The application landscape includes modern and legacy technologies, ensuring a robust platform used daily. Main Responsibilities: Contribute to the development, maintenance, and operation of the team’s solutions Learn and understand the domain, architecture, and surrounding integrations Participate in operational activities, including monitoring, patching, and ensuring high availability Support troubleshooting, analysis, and technical improvements Help simplify and modernize existing solutions Contribute to knowledge sharing and long-term continuity Help ensure a stable and reliable platform used daily by approximately 9,000 employees Key Requirements: Strong Java development competencies (5+ years of experience) Experience in complex enterprise environments Ability to navigate both modern and legacy solutions. Pragmatic and collaborative mindset Nice to Have: Experience with enterprise application platforms such as WebSphere, Tomcat, JBoss, or similar technologies is considered an advantage, as large parts of the application landscape rely on WebSphere-based solutions.

🏢 Summary: Senior technical role leading the design, optimization, and delivery of core business applications within a large IT transformation program. The position focuses on Java-based microservices, cloud and DevOps adoption, and collaboration with architecture and infrastructure teams. It combines hands-on development expertise with technical leadership across strategic platforms. 🗂️ Requirements: 6+ years of experience with Java microservices, Strong experience with JEE and Spring Boot, Experience in API and REST development, Proficiency in Kubernetes, Proficiency in Python, Experience with cloud migration projects, Hands-on experience with Oracle Database and WebLogic, Experience with messaging systems such as IBM MQ or WebSphere, Knowledge of IT security standards, Understanding of functional and technical architecture principles, Fluency in English 📃 Skills: Java, JEE, SpringBoot, REST, API, Microservices, Kubernetes, Python, Oracle, WebLogic, IBMMQ, WebSphere, DevOps, Agile, CloudMigration, Architecture, Security 🏢 Description: Key Responsibilities: Technical Leadership: Provides expert technical guidelines and support to IT analysts and development teams. Application Optimization: Identifies improvement and optimization opportunities for major core business applications. Strategic Delivery: Contributes to the delivery of high-priority projects within core business platforms. Infrastructure Collaboration: Partners with Architects, Security, and Infrastructure teams to design and evolve technical solutions. IT Transformation: Drives the adoption of DevOps, Agile methodologies, and AI readiness as part of broader group transformation programs. Technical Requirements: Java Expertise: Over 6 years of experience with Java microservices, JEE, Spring Boot, and API/REST development. Cloud & DevOps: Proficiency in Kubernetes and Python, with cloud migration expertise and DevOps knowledge listed as significant advantages. Data & Middleware: Experience with Oracle components (Database, WebLogic) and messaging flows such as IBM MQ or WebSphere. Standards & Architecture: Deep awareness of IT security standards, quality metrics, and functional/technical architecture principles. Professional Skills: Fluency in English with the ability to present complex technical topics to senior stakeholders.

🏢 Summary: Senior Java Tech Lead role focused on leading backend development, defining technical architecture, mentoring engineers, and delivering scalable microservices solutions in an Agile environment. The position combines hands-on Java development with technical leadership, code quality oversight, and collaboration with stakeholders. Experience with Spring, Oracle SQL, distributed systems, and backend security is required. 🗂️ Requirements: Experience leading technical teams, Strong Java 11-25 expertise, Advanced knowledge of memory management, Advanced knowledge of concurrency, JDBC experience, Experience with Spring Boot, Experience with JPA, Experience with Hibernate, RDBMS knowledge, Oracle SQL development, Query optimization skills, Microservices architecture knowledge, Asynchronous messaging experience, REST API development, OpenAPI knowledge, API-First approach experience, Git proficiency, Maven proficiency, Backend security knowledge, Unit testing experience, Integration testing experience, Fluent English 📃 Skills: Java, JDBC, Spring, SpringBoot, JPA, Hibernate, Oracle, SQL, Microservices, REST, OpenAPI, Swagger, Git, Maven, Kubernetes, Ansible, OpenSearch, Jenkins, SonarQube 🏢 Description: Java Tech Lead We are looking for a seasoned Java Developer with natural leadership qualities. In this role, you won't just write clean, scalable code—you will champion the technical direction, unblock your engineering team, and act as a bridge between technical execution and business vision. Key Responsibilities Technical Leadership: Spearhead architectural and solutioning discussions with stakeholders to map out the best technical paths. Team Empowerment: Actively remove bottlenecks within the delivery pipeline and mentor team members to help elevate their technical skills. Quality Assurance: Guard technical standards, ensuring all deliverables align with security benchmarks, code quality metrics, and engineering best practices. Backend Development: Drive hands-on development across multiple applications, tackling both brand-new greenfield projects and the evolution of existing systems. Collaboration & Process: Drive proactive technical analysis, conduct thorough code reviews, and actively participate in Scrum ceremonies. Requirements Leadership & Soft Skills: Exceptional communication and coordination skills. Proven ability to identify the technical critical path and take decisive steps to ensure successful delivery. A strong sense of ownership, multitasking abilities, and a highly proactive, self-sufficient mindset. Technical Expertise: Strong command of Java (from version 11 up to 25) and advanced concepts, including memory management, concurrency, and JDBC. Extensive experience with the Spring ecosystem (Spring Boot 2 to 4) and JPA/Hibernate . Solid RDBMS experience, with a specific focus on Oracle SQL development and query optimization . Deep understanding of microservices architecture , asynchronous messaging systems, and web communication ( REST, OpenAPI/Swagger, and API-First approach ). Everyday proficiency with Git and Maven . Sound knowledge of backend security practices and a commitment to writing clean, high-coverage unit and integration tests. Fluency in English (both written and spoken). Nice to Have Hands-on experience with cloud-native and infrastructure tools like Kubernetes , Ansible , or OpenSearch . Familiarity with build and deployment automation ( CI/CD via Jenkins, SonarQube ). Experience implementing automated testing frameworks. Past involvement in high-level technical architecture and design. Experience working within geographically distributed, international teams.

🏢 Summary: Opportunity for an experienced Java Tech Lead to combine hands-on backend development with technical leadership, driving architectural decisions and guiding a development team. The role focuses on designing scalable backend services with Java and Spring Boot while ensuring alignment with business goals and engineering best practices. Hybrid work model with production release support responsibilities. 🗂️ Requirements: Minimum 8 years of professional Java software engineering experience, Previous experience in a Technical Lead or similar leadership role, Strong expertise in Java 17+, Strong expertise in Spring Boot, Solid understanding of software architecture, Experience with distributed systems, Experience designing RESTful APIs, Fluent English, Fluent Polish, Residence in Poland, Availability for hybrid work (3 days per week in office), Availability to support production releases 1–2 weekends per month 📃 Skills: Java, Spring, SpringBoot, REST, API, Microservices, DistributedSystems 🏢 Description: We are looking for an experienced Java Tech Lead who will play a key role in shaping technical solutions, guiding the development team, and ensuring the successful delivery of high-quality software products. This position combines hands-on development with technical leadership. You will be responsible for driving architectural decisions, mentoring engineers, collaborating with Product Owners and Business Stakeholders, and ensuring that technical solutions align with business objectives and engineering best practices. Your tasks Leading technical design discussions and driving architectural decisions across the team Evaluating and proposing technical solutions to ensure scalability, maintainability, and performance Providing technical guidance and support to developers throughout the software development lifecycle Designing and developing backend services and REST APIs using Java and Spring Boot Performing hands-on coding for complex features and critical system components Supporting production releases and ensuring platform stability Requirements At least 8 years of professional experience in software engineering with Java Previous experience as a Technical Lead, Lead Developer, Senior Developer with mentoring responsibilities, or a similar leadership role Strong expertise in Java 17+ and Spring Boot Solid understanding of software architecture, distributed systems, and RESTful API design Fluency in English Open to a hybrid working model with presence in the office 3 days per week Availability to support production releases approximately 1–2 times per month during weekends (around 2 hours per occurrence) Fluent Polish required Residing in Poland required 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: Role combining business analysis and senior Java development for a large-scale Terminal Management System, focused on designing, upgrading, integrating, and maintaining distributed enterprise applications. The project involves legacy system modernization, reverse engineering, automated testing, and work with complex integrations and distributed transactions. Hybrid work model in Warsaw with a 1-year contract and potential long-term hiring. 🗂️ Requirements: Work from Warsaw office 4 days per week, Java 8+, Object-oriented programming, Spring, Spring Boot, SQL, Scrum, Hibernate, JPA, JEE, RabbitMQ, Maven, Git, GitLab, CI/CD, Jenkins, Nexus, Jira, Oracle, REST, System integration, Distributed systems, JBoss, WildFly, Fortify, Sonatype, English B2, Experience in design and implementation of application components, Experience with documentation and testing 📃 Skills: Java, Spring, SpringBoot, SQL, Scrum, Hibernate, JPA, JEE, RabbitMQ, Maven, Git, GitLab, Jenkins, Nexus, Jira, Oracle, REST, JBoss, WildFly, Fortify, Sonatype, Hazelcast, SOAP, RMI, GWT, GWTExt, Angular, Linux, Docker 🏢 Description: Analyst (70%) Senior Java Developer (30%) Terminal Management System •         Design and implementation of IT solutions based on the presented analytical and technical documentation; •         Reviewing analytical documentation; •         Creating technical documentation; • Technical upgrade for existing system; • Working with legacy code • Reverse engineering based on: o existing source code o existing functional and technical documentation o collected and documented business processes, o user interface to the system and accessing databases • Defining and building test cases for automatic tests Job Requirements • Ability to work from the office in Warsaw (weekly: 4 days at office + 1 day remotely); • Very good knowledge of Java 8+ (17 - 21) and object-oriented programming issues; • Experience in independent design, implementation, documentation and testing of application components; • Very good and p ractical knowledge of Spring, Spring Boot, SQL, Scrum, Hibernate/JPA and JEE frameworks; • Practical knowledge with message queue systems, particularly RabbitMQ; • Practical knowledge of tools supporting the software development process: Maven, Git, Gitlab, Gitlab CI/CD, Jenkins, Nexus, Jira; • Knowledge of relational databases, in particular Oracle; • Practical knowledge of RESTful API design; • Experience in system integration; • Experience with distributed systems; • Experience with application servers, JBoss/WildFly; ·  Knowledge of scanning tools (Fortify, Sonatype..) • Knowledge of English / B2; Nice to have : ·         Angular ·         Linux server ·         Docker Description of the area of involvement TMS (Terminal Management System) is used to manage a very large number of payment terminals (300k+), it gives users a uniform way to manage different terminals from different hardware vendors. TMS has a complex architecture, consisting of two components TMS (1 WildFly instance) providing GUI and implementing some business functions and RTMS (3 Spring-boot instances) implementing most of the business functionalities. A gradual migration from TMS to RTMS is being carried out. The system intensively uses Spring, Hibernate and RabbitMQ. The system has distributed transactions (different two-phase-commit, saga approaches) and distributed cache (Hazelcast). TMS is integrated with many internal and external systems (via REST, SOAP, RMI, direct database connections and database links). The GUI is written in GWT and GWTExt. TMS is subjected to regular application scans and vulnerabilities removal 1 year project with possibility for hiring after this time.

🏢 Summary: The role combines Senior Java Development (70%) with system analysis (30%) for a complex Terminal Management System managing 300k+ payment terminals. It involves designing, upgrading and integrating distributed system components, working with legacy code, and supporting migration to Spring Boot-based architecture. The project includes system integration, reverse engineering, automated testing and vulnerability remediation in a large-scale enterprise environment. 🗂️ Requirements: Very good knowledge of Java 8+ (17–21), Strong object-oriented programming knowledge, Experience in independent design, implementation, documentation and testing of application components, Very good practical knowledge of Spring and Spring Boot, Very good practical knowledge of Hibernate/JPA and JEE, Strong SQL knowledge, Knowledge of relational databases, especially Oracle, Experience with message queue systems (RabbitMQ), Practical knowledge of RESTful API design, Experience with distributed systems, Experience with system integration, Experience with application servers (JBoss/WildFly), Knowledge of Maven, Git, GitLab, GitLab CI/CD, Jenkins, Nexus, Jira, Knowledge of Scrum methodology, Knowledge of scanning tools (Fortify, Sonatype), Ability to work from Warsaw office 4 days per week 📃 Skills: Java, Spring, SpringBoot, Hibernate, JPA, JEE, SQL, Oracle, RabbitMQ, REST, Maven, Git, GitLab, Jenkins, Nexus, Jira, JBoss, WildFly, Hazelcast, SOAP, RMI, GWT, GWTExt, Fortify, Sonatype, Scrum 🏢 Description: Analyst (70%) Senior Java Developer (30%) Terminal Management System •         Design and implementation of IT solutions based on the presented analytical and technical documentation; •         Reviewing analytical documentation; •         Creating technical documentation; • Technical upgrade for existing system; • Working with legacy code • Reverse engineering based on: o existing source code o existing functional and technical documentation o collected and documented business processes, o user interface to the system and accessing databases • Defining and building test cases for automatic tests Job Requirements • Ability to work from the office in Warsaw (weekly: 4 days at office + 1 day remotely); • Very good knowledge of Java 8+ (17 - 21) and object-oriented programming issues; • Experience in independent design, implementation, documentation and testing of application components; • Very good and p ractical knowledge of Spring, Spring Boot, SQL, Scrum, Hibernate/JPA and JEE frameworks; • Practical knowledge with message queue systems, particularly RabbitMQ; • Practical knowledge of tools supporting the software development process: Maven, Git, Gitlab, Gitlab CI/CD, Jenkins, Nexus, Jira; • Knowledge of relational databases, in particular Oracle; • Practical knowledge of RESTful API design; • Experience in system integration; • Experience with distributed systems; • Experience with application servers, JBoss/WildFly; ·  Knowledge of scanning tools (Fortify, Sonatype..) • Knowledge of English / B2; Nice to have : ·         Angular ·         Linux server ·         Docker Description of the area of involvement TMS (Terminal Management System) is used to manage a very large number of payment terminals (300k+), it gives users a uniform way to manage different terminals from different hardware vendors. TMS has a complex architecture, consisting of two components TMS (1 WildFly instance) providing GUI and implementing some business functions and RTMS (3 Spring-boot instances) implementing most of the business functionalities. A gradual migration from TMS to RTMS is being carried out. The system intensively uses Spring, Hibernate and RabbitMQ. The system has distributed transactions (different two-phase-commit, saga approaches) and distributed cache (Hazelcast). TMS is integrated with many internal and external systems (via REST, SOAP, RMI, direct database connections and database links). The GUI is written in GWT and GWTExt. TMS is subjected to regular application scans and vulnerabilities removal 1 year project with possibility for hiring after this time.

🏢 Summary: Senior Java Developer / Technical Lead role focused on building and enhancing high-performance, low-latency trading systems. The position drives end-to-end delivery of complex engineering initiatives, contributes to architecture decisions, and improves system scalability and reliability. It involves close collaboration with engineering and business stakeholders while mentoring other developers and evolving technical standards. 🗂️ Requirements: 8+ years of software development experience, Strong proficiency in Java, Solid understanding of concurrent and multithreaded programming, Experience building distributed systems, Proven ability to deliver complex technical solutions, Experience working in cross-functional environments, Strong communication skills, Ability to work in dynamic, fast-paced environments, Familiarity with modern development tools including AI-supported solutions, Willingness to work with technologies beyond Java 📃 Skills: Java, Concurrency, Multithreading, DistributedSystems, LowLatency, TradingSystems, Architecture, AItools 🏢 Description: Senior Java Developer / Technical Lead Responsibilities Develop and enhance high-performance components within a low-latency trading environment. Drive delivery of key engineering initiatives across the full lifecycle — from concept and design to deployment and support. Take ownership of complex technical areas, working cross-functionally with engineering and business stakeholders. Contribute to architectural decisions and help evolve engineering standards and best practices. Support and guide other engineers through knowledge sharing, collaboration, and hands-on problem solving. Participate in design discussions and code reviews to ensure high-quality solutions. Continuously improve system performance, scalability, and reliability. Work closely with business teams to translate requirements into technical solutions. Contribute to the ongoing modernization and simplification of existing systems and platforms. Requirements 8+ years of experience in software development, with a strong focus on Java Solid understanding of concurrent and multithreaded programming, Experience in a building financial/trading systems is a big plus Experience in building distributed systems. Proven ability to deliver complex technical solutions. Experience working in collaborative, cross-functional environments. Strong communication skills. Ability to work effectively in dynamic, fast-paced environments. Familiarity with modern development tools, including AI-supported solutions. Exposure to or willingness to work with technologies beyond Java

🏢 Summary: IT Operations Specialist role focused on supporting production systems, ensuring stable and secure software releases, and handling incident management in collaboration with development and release teams. The position involves monitoring, troubleshooting, and maintaining microservices-based environments using modern DevOps and containerization technologies. 🗂️ Requirements: Experience with Docker, Experience with Kubernetes, Experience with CI/CD tools (Jenkins), Experience with GitHub or Bitbucket, Hands-on experience with Kafka, Basic knowledge of SQL, Knowledge of LDAP, Kerberos, JWT, Knowledge of OpenSSL and keytool, Understanding of HTTPS, Experience with Splunk, Experience with Prometheus, InfluxDB, or Grafana, Understanding of microservices architecture 📃 Skills: Docker, Kubernetes, Jenkins, GitHub, Bitbucket, Kafka, SQL, LDAP, Kerberos, JWT, OpenSSL, keytool, HTTPS, Splunk, Prometheus, InfluxDB, Grafana, Microservices, PostgreSQL 🏢 Description: Job Description: We are looking for an IT Operations Specialist to support the maintenance and delivery of systems in a production environment. The role involves close collaboration with development and release teams to ensure stable and secure system operations. Responsibilities: Supporting Release Management in delivering software to the production environment Monitoring, investigating, and resolving issues in production systems Handling incidents and performing root cause analysis (RCA) Acting as L2 support for incident management Requirements (must-have): Experience with Docker and Kubernetes Familiarity with CI/CD tools such as Jenkins Experience with code repositories: GitHub or Bitbucket Hands-on experience with Kafka Basic understanding of SQL Knowledge of authentication and authorization mechanisms (LDAP, Kerberos, JWT) Understanding of cryptography tools (OpenSSL, keytool) Knowledge of secure communication protocols (HTTPS) Experience with logging tools (Splunk) Familiarity with monitoring and alerting tools (Prometheus, InfluxDB, Grafana) Understanding of microservices architecture Good interpersonal and communication skills Nice to have: Experience with PostgreSQL What we offer: Opportunity to work with modern technologies Involvement in large-scale, impactful projects Professional growth and development opportunities Collaboration within an experienced and supportive team

🏢 Summary: Senior Java Developer role focused on designing, implementing, and maintaining a large-scale Terminal Management System handling 300k+ payment terminals. The position involves working with distributed systems, legacy code, system integrations, and security vulnerability remediation in a hybrid Warsaw-based setup. The project includes migration from legacy architecture to Spring Boot-based services with potential long-term hiring after the initial one-year contract. 🗂️ Requirements: Availability in the Polish time zone, Ability to work from the Warsaw office 4 days per week, Java 8+ proficiency, Object-oriented programming knowledge, Experience designing and implementing application components, Experience documenting and testing application components, Spring knowledge, Spring Boot knowledge, SQL knowledge, Scrum knowledge, Hibernate/JPA knowledge, JEE knowledge, RabbitMQ experience, Maven knowledge, Git knowledge, GitLab knowledge, GitLab CI/CD knowledge, Jenkins knowledge, Nexus knowledge, Jira knowledge, Oracle database knowledge, RESTful API design experience, System integration experience, Distributed systems experience, JBoss/WildFly experience, Fortify knowledge, Sonatype knowledge, English level B2 📃 Skills: Java, Spring, SpringBoot, SQL, Scrum, Hibernate, JPA, JEE, RabbitMQ, Maven, Git, GitLab, Jenkins, Nexus, Jira, Oracle, REST, JBoss, WildFly, Fortify, Sonatype, Hazelcast, SOAP, RMI, GWT, GWTExt, Angular, Linux, Docker 🏢 Description: Senior Java Developer (TMS) •         Design and implementation of IT solutions based on the presented analytical and technical documentation; •         Reviewing analytical documentation; •         Creating technical documentation; •         Technical upgrade for existing system; •         Working with legacy code •         Conducting regular scans in the application and removing vulnerabilities Job Requirements • Fully available in the Polish time zone; • Ability to work from the office in Warsaw (weekly: 4 days at office + 1 day remotely); • Very good knowledge of Java 8+ and object-oriented programming issues; • Experience in independent design, implementation, documentation and testing of application components; • Very good and p ractical knowledge of Spring, Spring Boot, SQL, Scrum, Hibernate/JPA and JEE frameworks; • Practical knowledge with message queue systems, particularly RabbitMQ; • Practical knowledge of tools supporting the software development process: Maven, Git, Gitlab, Gitlab CI/CD, Jenkins, Nexus, Jira; • Knowledge of relational databases, in particular Oracle; • Practical knowledge of RESTful API design; • Experience in system integration; • Experience with distributed systems; • Experience with application servers, JBoss/WildFly; ·  Knowledge of scanning tools (Fortify, Sonatype..) • Knowledge of English / B2; Nice to have: ·         Angular ·         Linux server ·         Docker Description of the area of involvement TMS (Terminal Management System) is used to manage a very large number of payment terminals (300k+), it gives users a uniform way to manage different terminals from different hardware vendors. TMS has a complex architecture, consisting of two components TMS (1 WildFly instance) providing GUI and implementing some business functions and RTMS (3 Spring-boot instances) implementing most of the business functionalities. A gradual migration from TMS to RTMS is being carried out. The system intensively uses Spring, Hibernate and RabbitMQ. The system has distributed transactions (different two-phase-commit, saga approaches) and distributed cache (Hazelcast). TMS is integrated with many internal and external systems (via REST, SOAP, RMI, direct database connections and database links). The GUI is written in GWT and GWTExt. 1 year project with possibility for hiring after this time.

🏢 Summary: 1-year project for a Senior Java Developer to design, implement, upgrade, and maintain a complex Terminal Management System handling 300k+ payment terminals. The role involves working with legacy code, distributed systems, system integrations, and ensuring application security through regular vulnerability scans. The system is based on Java and Spring ecosystem with intensive use of messaging and transactional mechanisms. 🗂️ Requirements: Very good knowledge of Java 8+, Strong understanding of object-oriented programming, Experience in designing and implementing application components, Practical knowledge of Spring and Spring Boot, Practical knowledge of SQL and relational databases, Experience with Hibernate and JPA, Knowledge of JEE frameworks, Experience with RabbitMQ or other message queues, Knowledge of Maven and Git, Experience with Gitlab and CI/CD pipelines, Experience with Jenkins and Nexus, Knowledge of Oracle database, Experience in RESTful API design, Experience in system integration, Experience with distributed systems, Experience with JBoss or WildFly, Knowledge of security scanning tools (Fortify, Sonatype) 📃 Skills: Java, Spring, SpringBoot, SQL, Hibernate, JPA, JEE, RabbitMQ, Maven, Git, Gitlab, CICD, Jenkins, Nexus, Jira, Oracle, REST, JBoss, WildFly, Fortify, Sonatype, Hazelcast, GWT, GWTExt, SOAP, RMI 🏢 Description: Senior Java Developer (TMS) •         Design and implementation of IT solutions based on the presented analytical and technical documentation; •         Reviewing analytical documentation; •         Creating technical documentation; •         Technical upgrade for existing system; •         Working with legacy code •         Conducting regular scans in the application and removing vulnerabilities Job Requirements • Fully available in the Polish time zone; • Ability to work from the office in Warsaw (weekly: 4 days at office + 1 day remotely); • Very good knowledge of Java 8+ and object-oriented programming issues; • Experience in independent design, implementation, documentation and testing of application components; • Very good and p ractical knowledge of Spring, Spring Boot, SQL, Scrum, Hibernate/JPA and JEE frameworks; • Practical knowledge with message queue systems, particularly RabbitMQ; • Practical knowledge of tools supporting the software development process: Maven, Git, Gitlab, Gitlab CI/CD, Jenkins, Nexus, Jira; • Knowledge of relational databases, in particular Oracle; • Practical knowledge of RESTful API design; • Experience in system integration; • Experience with distributed systems; • Experience with application servers, JBoss/WildFly; ·  Knowledge of scanning tools (Fortify, Sonatype..) • Knowledge of English / B2; Nice to have: ·         Angular ·         Linux server ·         Docker Description of the area of involvement TMS (Terminal Management System) is used to manage a very large number of payment terminals (300k+), it gives users a uniform way to manage different terminals from different hardware vendors. TMS has a complex architecture, consisting of two components TMS (1 WildFly instance) providing GUI and implementing some business functions and RTMS (3 Spring-boot instances) implementing most of the business functionalities. A gradual migration from TMS to RTMS is being carried out. The system intensively uses Spring, Hibernate and RabbitMQ. The system has distributed transactions (different two-phase-commit, saga approaches) and distributed cache (Hazelcast). TMS is integrated with many internal and external systems (via REST, SOAP, RMI, direct database connections and database links). The GUI is written in GWT and GWTExt. 1 year project with possibility for hiring after this time.