Java/Kotlin Software Engineer (Data Tracking)

🏢 Summary: Hands-on Tech Lead role focused on designing and delivering scalable backend platforms and RESTful microservices for a global e-commerce and wellness technology ecosystem. The position involves technical leadership, backend development with Kotlin/Java and Spring Boot, mentoring engineers, and driving architecture decisions in a cloud-native environment. The role offers a hybrid work model in Warsaw with a competitive salary and benefits. 🗂️ Requirements: 6+ years of software development experience, Backend development experience with Java or Kotlin, Experience building and scaling RESTful microservices, Hands-on experience with Spring Boot, Hands-on experience with Docker, Hands-on experience with Kubernetes, Experience with AWS or GCP, Experience with PostgreSQL, MongoDB, DynamoDB, or Elasticsearch, Experience with unit testing and test-driven development, Experience with CI/CD pipelines, Experience leading technical projects and mentoring engineers, Ability to guide architecture decisions and delivery planning, Experience working in agile cross-functional teams 📃 Skills: Kotlin, Java, Spring, SpringBoot, Microservices, Docker, Kubernetes, AWS, GCP, PostgreSQL, MongoDB, DynamoDB, Elasticsearch, CI/CD, Datadog, REST, TDD, DevOps, Agile 🏢 Description: We are hiring on behalf of our client, a global innovator in fitness and wellness technology. Their mission is to empower people to live fit, strong, long, and happy lives by delivering integrated experiences to millions of members anytime, anywhere. We are looking for a Kotlin/Java Tech Lead to join an e-commerce engineering team. In this role, you will lead the design and delivery of scalable backend platforms and services powering the company's customer-facing commerce experience across web, retail, and other sales channels. This is a hands-on technical leadership role. You will guide engineering decisions, mentor other engineers, partner closely with product and design, and help the team deliver high-impact initiatives with strong engineering quality, scalability, and reliability. Key takeaways: Stack: Kotlin/Java, Spring Boot, microservices, Docker, Kubernetes, AWS, PostgreSQL, CI/CD, Datadog, technical leadership experience Salary: 26 000 PLN - 30 000 PLN gross on the Contract of Employment Working model : Hybrid - 3 days/week from the office Location: ul. Grzybowska, Warsaw Recruitment process : A call with MOTIFE Recruiter Panel interviews with the team (coding, architecture, and cross-collaboration interviews) Responsibilities: Technical Leadership Lead the delivery of small to large engineering initiatives, from technical discovery through implementation and production readiness. Guide the team in making strategic backend architecture decisions that support scalability, performance, and long-term maintainability. Own technical trade-offs and ensure solutions are aligned with business goals, user needs, and engineering standards. Mentor engineers through design reviews, code reviews, and day-to-day technical collaboration. Backend Engineering Build and improve backend platforms and services. Design and scale RESTful microservices used across web, retail, and other sales channels. Develop backend services using technologies such as Java, Kotlin, Spring Boot, Docker, and Kubernetes. Work with data stores such as PostgreSQL, MongoDB, DynamoDB, Elasticsearch, or similar technologies. Delivery & Product Collaboration Partner closely with product managers, designers, and peer engineers to scope, build, and deliver end-to-end features. Translate product strategy and business requirements into reliable, scalable technical solutions. Drive iterative delivery in an agile engineering environment. Maintain strong relationships with stakeholders and ensure clear communication around scope, risks, and delivery progress. Engineering Excellence Promote strong engineering practices, including unit testing, test-driven development, CI/CD, observability, and production ownership. Apply a DevOps mindset to build services that are reliable, observable, and easy to operate. Requirements: Technical Expertise 6+ years of professional software development experience. Strong backend engineering experience with Java or Kotlin. Proven experience building and scaling RESTful microservices. Hands-on experience with Spring Boot, Docker, and Kubernetes. Experience with cloud infrastructure such as AWS or GCP. Familiarity with data stores such as PostgreSQL, MongoDB, DynamoDB, Elasticsearch, or similar technologies. Experience with unit testing, test-driven development, and CI/CD pipelines. Leadership Experience Experience leading engineers to deliver high-impact technical projects. Proven ability to mentor junior and mid-level engineers and support their technical growth. Ability to guide technical decision-making, architecture discussions, and delivery planning. Experience with end-to-end feature ownership in a cross-functional product environment. Collaboration & Mindset Strong communication skills and ability to work effectively with product, design, and engineering stakeholders. Agile mindset with a strong focus on iterative design and delivery. High ownership, strong delivery orientation, and ability to operate in a fast-moving engineering environment. Strong desire to learn, share knowledge, and help engineers achieve their highest potential. What we offer: 100% paid medical care Multisport Creative tax (KUP) Home office allowance MacBook Pro Apply now If you enjoy technical leadership, hands-on backend engineering, and building platforms used at scale, this role is a strong opportunity to make a real impact. Please apply via our careers page and submit your CV in English.

🏢 Summary: Engineering role focused on building and modernizing large-scale settlement and cash processing systems that power financial operations and regulatory reporting. The position involves designing scalable backend and data platforms processing millions of daily transactions, while collaborating closely with Finance and Product stakeholders. Key initiatives include revamping the historical settlement system and expanding into payment fees analytics. 🗂️ Requirements: Deep expertise in backend engineering (Java) or data engineering, Experience processing large-scale transactional and financial data, Experience with batch or streaming frameworks (Spark, Flink, or Beam), Proficiency in Scala for data engineering, Experience building scalable backend systems in Java, Strong understanding of system design, data structures, and algorithms, Experience with cloud-native development, preferably Google Cloud Platform, Ability to design reliable, maintainable, and auditable systems 📃 Skills: Java, Scala, Spark, Flink, Beam, GCP, SQL, Algorithms, DataStructures, Cloud, Backend, DataEngineering 🏢 Description: Our team is building the settlement and cash processing systems that drive how cash from our customers is processed and accounted for — enabling reliable, scalable financial operations across every market, product line, and partner. Our systems are essential to our stakeholders’ ability to track and report revenue and taxes, supporting all of our core business lines. As engineers on this team, we design and maintain the backend and data platform capabilities that power millions of transactions each day with precision. We build services that handle settlement and bank transactions, produce compliant financial records, and support regulatory requirements across global markets — all while staying agile to keep up with our evolving business model and staying in sync with our many payment partners. We build robust services that provide clarity over what’s happening under the hood of millions of daily transactions, enabling quick action to any disruption. Our modular, process-oriented components simplify the development, maintenance, and scaling of the critical Order to Cash enterprise process that underpin the financial operations. We are starting two major initiatives: a revamp of our historical settlement system in order to align with our modularity strategy as well as expanding into the adjacent domain of payment fees, which is a massive cost center in need of good data for analytics in order to optimize the space. We’re looking for engineers passionate about building complex, high-impact systems. You’ll work closely with stakeholders in Finance (Accounting and Payments), Product, and Engineering to design solutions that are scalable, auditable, and robust. If you’re energized by the challenge of transforming intricate business processes into clean, extensible platforms we’d love to have you on the team. What You’ll Do - Gain deep expertise in client’s revenue and settlement systems, understanding how it enables financial operations, compliance, and strategic decision-making across the company. - Design and implement scalable backend and data systems that process millions of transactions daily to enable the cash-application process and financial reporting. - Build intuitive, self-serve tools that empower Finance teams to define and manage product-specific revenue and settlement configuration independently, without requiring engineering involvement. - Develop and enhance modular platform capabilities that encodes critical enterprise workflows, promoting consistency, reusability, and ease of maintenance across financial systems. - Partner closely with Engineers, Product and Finance stakeholders to design systems that are scalable, auditable, and highly reliable. - Champion engineering best practices, strong architectural design, and operational excellence across backend and data platforms. - Foster a collaborative team culture rooted in shared ownership, constructive feedback, and continuous improvement. Who You Are - You possess a T-shaped engineering skill set — deep expertise in either data or backend engineering (Java), while growing the ability to work effectively across both. For this role, experience or familiarity with processing large-scale transactional and financial data, using batch/streaming frameworks like Spark, Flink, or Beam (with Scala for data engineering), and building scalable backend systems in Java is a strong advantage. - You possess a foundational understanding of system design, data structures, and algorithms, coupled with a strong desire to learn quickly, embrace feedback, and continuously improve your technical skills. - You’re familiar with cloud-native development and deployment, ideally within the Google Cloud Platform. - You think critically about system design and strive to build solutions that are reliable, maintainable, and auditable at scale. - You have good communication skills and can articulate your ideas and ask clarifying questions. - You love collaborating with others. - You thrive in ambiguous and fast-changing environments, and know how to make progress even when requirements are evolving. - You approach platform engineering with empathy for your users — prioritizing usability, configurability, and long-term sustainability. - You care deeply about code quality, testing, and documentation, and you aim to build systems that are easy to understand and operate. - You enjoy collaborating across functions and bring clarity and alignment when working with engineering, finance, and product partners. - You’re naturally curious, self-motivated, and always looking for ways to grow your technical skills and improve how things are done. Other Details Start: Asap or August Length: 6 months Workplace: Sweden

🏢 Summary: Backend engineering role focused on designing and scaling assortment management systems in a distributed retail environment using Kotlin, Spring Boot, Kafka, AWS, and Kubernetes. The position involves leading backend architecture, building event-driven integrations, optimizing system reliability, and collaborating with product and engineering stakeholders. Candidates will also mentor engineers and drive best practices across scalable cloud-native platforms. 🗂️ Requirements: Degree in Computer Science or related technical field, 6+ years of backend development experience, Experience with Kotlin, Experience with Spring Boot, Strong knowledge of REST APIs, Experience with microservices, Experience with distributed systems, Experience with event-driven architectures, Hands-on experience with Kafka, Experience with asynchronous processing, Experience with AWS, Experience with Kubernetes, Experience with Amazon EKS, Experience with PostgreSQL, Knowledge of CI/CD, Experience with containerization, Knowledge of observability tooling, Knowledge of OAuth2, Knowledge of IAM, English proficiency, Polish proficiency, Availability for hybrid work in Katowice 📃 Skills: Kotlin, Spring, SpringBoot, REST, Microservices, Kafka, AWS, Kubernetes, EKS, PostgreSQL, CI/CD, Docker, OAuth2, IAM 🏢 Description: Responsibilities We are looking for a strong backend engineer who wants to design and scale core systems powering product and assortment management across a large retail ecosystem . You will take ownership of backend architecture and system evolution within the assortment management domain , building scalable services and integrations across a complex, event-driven enterprise landscape. You act as a technical driver within the team, working closely with architects, product owners and stakeholders to deliver robust, high-quality solutions. Your key responsibilities include: Design and develop scalable backend services , APIs and integrations using Kotlin and Spring Boot within distributed systems. Translate complex business and product data requirements into robust , maintainable and scalable system designs . Lead the design and evolution of event - driven architectures and asynchronous processing using Kafka . Design and integrate backend systems within AWS and Kubernetes -based enterprise environments. Drive data modeling and persistence strategies using PostgreSQL and cloud - native approaches. Act as a technical interface between business , product and engineering teams, leading solution design and backlog refinement . Drive engineering best practices , observability , reliability and architectural consistency across the platform. Lead troubleshooting , optimization and continuous improvement initiatives while mentoring less experienced engineers. Benefits Motivizer Benefits Platform to choose and manage all your benefits in one place. You receive a budget (550 PLN monthly). You can choose medical care package, meal tickets, sports cards (we have Multisport and on preferential terms, we have membership cards to one of the most popular Gyms), cinema tickets, shop vouchers, discounts and many more. Language Courses – you'll have access to a multi-language learning platform enabling you to practice your language skills and learn new ones! Regular and systematic further training opportunities - both internally and from external providers. We support your ongoing learning and development. Cooperation within an internal community is our everyday reality. We have networking events, coding challenges, and company parties for different occasions. Qualifications Completed university degree in Computer Science or a comparable technical field. 6+ years of professional experience in backend development using Kotlin and Spring Boot in complex environments. Strong expertise in REST APIs , microservices , distributed systems and event - driven architectures . Deep hands-on experience with Kafka and asynchronous processing patterns in production systems. Strong experience with AWS and Kubernetes (including Amazon EKS ) in scalable environments. Solid experience with PostgreSQL and designing performant, reliable data models. Experience with CI/CD , containerization , observability tooling and modern security concepts (OAuth2, IAM). Strong communication skills in English and Polish , with readiness to work in a hybrid model in Katowice . About OBI Smart Technologies WHO ARE WE: We are a joint venture between OBI and Reply Group, responsible for co-designing, building and operating mission-critical digital platforms for commerce, customer service, and omnichannel retail. OUR MISSION: " We unite technology leadership with deep retail vision to implement standardized processes and scalable digital products that drive efficient support for one of Europe’s largest DIY retailers. Leveraging proven best practices, we advance the internationalization of products and the digital mindset of our partners, delivering consistent and business-critical solutions to support the targets of our customer. "

🏢 Summary: Senior backend engineering role focused on designing and scaling assortment management systems in a large retail ecosystem using Kotlin, Spring Boot, Kafka, AWS, and Kubernetes. The position involves building distributed, event-driven services, leading backend architecture evolution, and collaborating with cross-functional teams to deliver scalable enterprise solutions. The role also includes mentoring engineers, driving engineering best practices, and improving system reliability and observability. 🗂️ Requirements: Degree in Computer Science or comparable technical field, 6+ years of backend development experience, Experience with Kotlin, Experience with Spring Boot, Expertise in REST APIs, Experience with microservices, Experience with distributed systems, Experience with event-driven architectures, Hands-on experience with Kafka, Experience with asynchronous processing, Experience with AWS, Experience with Kubernetes, Experience with Amazon EKS, Experience with PostgreSQL, Experience with CI/CD, Experience with containerization, Knowledge of observability tooling, Knowledge of OAuth2, Knowledge of IAM, English proficiency, Polish proficiency, Readiness to work in hybrid model in Katowice 📃 Skills: Kotlin, Spring, SpringBoot, REST, Microservices, Kafka, AWS, Kubernetes, EKS, PostgreSQL, CI/CD, Docker, OAuth2, IAM 🏢 Description: Responsibilities We are looking for a strong backend engineer who wants to design and scale core systems powering product and assortment management across a large retail ecosystem . You will take ownership of backend architecture and system evolution within the assortment management domain , building scalable services and integrations across a complex, event-driven enterprise landscape. You act as a technical driver within the team, working closely with architects, product owners and stakeholders to deliver robust, high-quality solutions. Your key responsibilities include: Design and develop scalable backend services , APIs and integrations using Kotlin and Spring Boot within distributed systems. Translate complex business and product data requirements into robust , maintainable and scalable system designs . Lead the design and evolution of event - driven architectures and asynchronous processing using Kafka . Design and integrate backend systems within AWS and Kubernetes -based enterprise environments. Drive data modeling and persistence strategies using PostgreSQL and cloud - native approaches. Act as a technical interface between business , product and engineering teams, leading solution design and backlog refinement . Drive engineering best practices , observability , reliability and architectural consistency across the platform. Lead troubleshooting , optimization and continuous improvement initiatives while mentoring less experienced engineers. Qualifications Completed university degree in Computer Science or a comparable technical field. 6+ years of professional experience in backend development using Kotlin and Spring Boot in complex environments. Strong expertise in REST APIs , microservices , distributed systems and event - driven architectures . Deep hands-on experience with Kafka and asynchronous processing patterns in production systems. Strong experience with AWS and Kubernetes (including Amazon EKS ) in scalable environments. Solid experience with PostgreSQL and designing performant, reliable data models. Experience with CI/CD , containerization , observability tooling and modern security concepts (OAuth2, IAM). Strong communication skills in English and Polish , with readiness to work in a hybrid model in Katowice . About OBI Smart Technologies WHO ARE WE: We are a joint venture between OBI and Reply Group, responsible for co-designing, building and operating mission-critical digital platforms for commerce, customer service, and omnichannel retail. OUR MISSION: " We unite technology leadership with deep retail vision to implement standardized processes and scalable digital products that drive efficient support for one of Europe’s largest DIY retailers. Leveraging proven best practices, we advance the internationalization of products and the digital mindset of our partners, delivering consistent and business-critical solutions to support the targets of our customer. "

🏢 Summary: The role involves designing and developing scalable backend systems in a microservices architecture using Java or Kotlin and Spring. The engineer will influence technical decisions while building payment and subscription platforms with event-driven communication and cloud-based solutions. The position includes working with modern architectural patterns and ensuring high code quality through testing and reviews. 🗂️ Requirements: Strong experience with Java and/or Kotlin, Solid knowledge of Spring and Spring Boot, Hands-on experience with SQL and relational databases, Experience with PostgreSQL, Proven experience with microservices architecture, Experience with event-driven systems, Practical experience with JUnit, Mockito, Testcontainers, Experience with AWS or GCP, Understanding of DDD, CQRS, Hexagonal Architecture, Experience with payment or subscription systems 📃 Skills: Java, Kotlin, Spring, SpringBoot, SQL, PostgreSQL, Microservices, Kafka, JUnit, Mockito, Testcontainers, AWS, GCP, DDD, CQRS, HexagonalArchitecture 🏢 Description: Senior Backend Engineer (Java/Kotlin) We are looking for an experienced Backend Engineer to join a team building modern, scalable systems based on a microservices architecture. This role offers real influence over technical decisions, system architecture, and the quality of delivered solutions—particularly within payment and subscription platforms. Responsibilities Design, develop, and maintain backend systems using Java or Kotlin and the Spring Framework Build and evolve microservices following DDD , CQRS , and Hexagonal Architecture principles Implement event-driven communication , ideally using Apache Kafka Work with relational databases ( PostgreSQL or other SQL databases ) and optimize queries Write unit and integration tests using JUnit, Mockito, and Testcontainers Contribute to the design and development of cloud-based solutions ( AWS or GCP ) Participate in code reviews and drive high engineering standards Collaborate closely with product and engineering teams to deliver business-critical features Requirements Strong experience with Java and/or Kotlin Solid knowledge of Spring / Spring Boot Hands-on experience with SQL and relational databases (preferably PostgreSQL ) Proven background in microservices-based architectures Experience with event-driven systems (Kafka is a strong plus) Practical experience with backend testing (JUnit, Mockito, Testcontainers) Experience working with cloud platforms ( AWS or GCP ) Good understanding of Domain-Driven Design (DDD) , CQRS , and Hexagonal Architecture Must-have: experience with payment systems and/or subscription-based platforms Nice to Have Experience working with high-scale, high-availability systems Knowledge of security and transactional data handling Background in product-driven, Agile environments

🏢 Summary: Technical leadership role focused on evolving and scaling a modular Java/Jakarta EE car-sharing platform, bridging engineering and company leadership. The position combines hands-on backend development, cloud infrastructure ownership, architecture decisions, and CI/CD optimization with team mentoring and operational responsibility. You will drive infrastructure improvements, security initiatives, and technical debt reduction while ensuring high availability and quality standards. 🗂️ Requirements: Several years of backend development experience with Java (Jakarta EE / Java EE / Spring) in production, Strong experience with Test-Driven Development (TDD), Proven experience as Tech Lead or Senior Engineer with team responsibility, Solid understanding of cloud infrastructure, ideally AWS (EC2, ECS, CloudWatch, S3), Experience with MongoDB or comparable NoSQL databases in production, Experience with CI/CD pipelines (GitLab CI, GitHub Actions, or similar), Ability to take ownership and deliver value independently 📃 Skills: Java, JakartaEE, Spring, AWS, EC2, ECS, CloudWatch, S3, MongoDB, NoSQL, GitLabCI, GitHubActions, TDD, Terraform, CloudFormation, React, ReactNative, Sentry, Crashlytics 🏢 Description: About Us We develop and operate an end-to-end platform for car sharing and vehicle rental, currently used by customers in Germany, Austria, and Spain. The platform is fully white-label capable and includes mobile apps, web applications, back-office tools, and integrations with telematics hardware, payment service providers, and KYC providers — all from a single, modular codebase. The backend is based on Java 17 / Jakarta EE 10 Payara , while the frontend is built with React / React Native . We are currently in a strategic growth phase and are now looking for an experienced technical leader to help shape the next stage of our development. The Role As Tech Lead , you will take on a central bridging role between Engineering and company leadership. You will work closely with the CTO, support them operationally, and ensure that the platform keeps pace with the company’s growth — both technically and organisationally. This position is designed for someone who can dive deep into the code while also keeping the bigger picture in mind. You are not afraid of a mature system with history — you see it as an opportunity. Technical Leadership & Architecture Further development and maintenance of the modular Java / Jakarta EE platform, including shared responsibility for architectural decisions Implementation of the identified infrastructure improvements: IaC Terraform / CloudFormation, multi-region setup, and disaster recovery plan Responsibility for implementing outstanding security measures Driving the migration of binary data from MongoDB to S3, as well as further technical debt reduction projects Evaluation and further development of the CI/CD pipelines GitLab CI and test coverage Processes & Team Organization Establishment of formal code review processes and consistent planning cycles within the development team Close collaboration with the CTO on the gradual handover of engineering and operational responsibilities Support in building a product management process aligned with customer requirements Mentoring of the junior frontend developer and support for the senior engineers Operations & Quality Shared responsibility for monitoring, alerting, and incident response AWS CloudWatch, Sentry, Crashlytics Automation of dependency vulnerability scanning within the CI pipeline Technical support for customer projects — from onboarding through to troubleshooting Must-Have Several years of experience in backend development with Java — Jakarta EE / Java EE / Spring — in production systems Strong experience with Test-Driven Development (TDD), as well as a strong quality mindset and interest in software craftsmanship Proven experience as a Tech Lead or Senior Engineer with team responsibility Solid understanding of cloud infrastructure, ideally AWS — EC2, ECS, CloudWatch, S3 Experience with MongoDB or comparable NoSQL databases in production environments Familiarity with CI/CD pipelines — GitLab CI, GitHub Actions, or similar — and modern deployment practices Hands-on mentality: you can deliver value immediately without requiring months of onboarding Nice-to-Have Knowledge of Infrastructure as Code — Terraform or CloudFormation Experience with React and/or React Native on the frontend Understanding of the mobility, car-sharing, or vehicle rental domains Experience in regulated environments or with GDPR compliance projects Knowledge of telematics hardware integrations or IoT-related systems Class B driving licence What We Offer One of the most technically impressive small platforms in the German mobility landscape — with real responsibility from day one Short decision-making paths and a high degree of freedom to shape things A well-established team with 5–10 years of shared platform history A modern tech stack: Java 17, Jakarta EE 10, React, React Native, GitLab CI/CD — without legacy burden 99.9% uptime — efficiency here is not an ambition, but a reality Hybrid working with an office in Berlin and flexible working hours Competitive salary, depending on experience and qualifications Active involvement in the strategic development of the company How to Apply We look forward to receiving your application — preferably including a short cover note, your CV, and, where relevant, references or GitHub projects. A formal cover letter is not required; we value genuine interest and technical depth more than formalities.

🏢 Summary: Backend Developer role focused on designing, building, and maintaining scalable Java and Kotlin-based applications and microservices within an international team. The position involves developing high-quality backend systems, collaborating with cross-functional teams, and optimizing distributed systems performance. The role emphasizes clean code, modern frameworks, and agile delivery practices. 🗂️ Requirements: 5+ years of backend development experience with Java 8+ and Kotlin, Strong knowledge of Spring Framework and Spring Boot, Experience building RESTful APIs and microservices, Experience with SQL and NoSQL databases, Understanding of Agile/Scrum methodologies 📃 Skills: Java, Kotlin, Spring, SpringBoot, REST, Microservices, SQL, NoSQL, PostgreSQL, MongoDB, Agile, Scrum 🏢 Description: We are looking for skilled Java & Kotlin Developers to join our growing technology team in Poland. As part of an international development group, you’ll design, build, and maintain scalable backend systems using Java and modern frameworks. You’ll collaborate closely with cross-functional teams to deliver high-quality, reliable, and efficient software solutions. Key Responsibilities Design, develop, and maintain Java-based applications and microservices. Write clean, efficient, and testable code following best practices and coding standards. Collaborate with front-end developers , DevOps engineers , and QA teams to ensure seamless integration and delivery. Participate in code reviews , architecture discussions, and agile ceremonies. Contribute to technical documentation and continuous improvement of development processes. Troubleshoot and optimize performance across distributed systems. Requirements 5+ years of experience in backend development using Java 8+ Kotlin . Strong understanding of Spring Framework / Spring Boot . Experience with RESTful APIs , microservices , and SQL / NoSQL databases (e.g., PostgreSQL, MongoDB). Knowledge of Agile / Scrum methodologies. Good command of English (B2 or higher) – Polish language skills are a plus. Nice to Have Experience with cloud platforms (AWS, Azure, or GCP). Familiarity with message brokers (Kafka, RabbitMQ). Knowledge of unit testing and test automation frameworks (JUnit, Mockito). Interest in DevOps or system design concepts. How to Apply If you’re passionate about building high-quality Java applications and want to be part of a dynamic engineering team, send your CV

🏢 Summary: The offer is for a Backend Developer role focused on building and maintaining high-performance, low-latency systems for advertising and e-commerce platforms. The position involves developing scalable microservices and APIs using Kotlin and Spring Boot, working with real-time event processing, and contributing to system architecture and scalability. The role also includes production support and collaboration within cross-functional engineering teams. 🗂️ Requirements: 3+ years of professional experience in Java backend development, Very good knowledge of Kotlin, Very good knowledge of Spring Boot, Hands-on experience with microservices architecture, Practical experience with NoSQL databases, Experience with MongoDB, Experience building and maintaining backend systems and APIs, Understanding of system design and scalable architecture principles, Experience with high-performance and high-scale systems, English level B2, Polish level C1, Experience with AI-powered coding assistants, Work permit for EU and ability to work from EU region, Availability for occasional visits to Warsaw office 📃 Skills: Java, Kotlin, Spring, SpringBoot, Microservices, MongoDB, NoSQL, REST, API, AI, Claude, Copilot, Cursor 🏢 Description: 🟣 You will be: developing and maintaining backend systems for advertising and e-commerce platforms, building low-latency, high-performance services processing large volumes of data, developing scalable microservices and APIs using Kotlin and Spring Boot, working on real-time event processing and advertising targeting mechanisms, contributing to architecture design and system scalability improvements, collaborating with stakeholders and supporting engineering best practices, including code reviews and code quality standards, participating in technical readiness/on-call support for production incidents a few days per month. 🟣 Your profile: 3+ years of professional experience in Java backend development, very good knowledge of Kotlin and Spring Boot, openness to occasional visits to the Warsaw office (1–2 days per quarter), hands-on experience with microservices architecture, practical experience working with NoSQL databases, especially MongoDB, experience building and maintaining backend systems and APIs, understanding of system design and scalable architecture principles, experience working with high-performance and high-scale systems, strong analytical thinking and problem-solving skills, ability to collaborate effectively with stakeholders and engineering teams, good communication skills in English (B2) and Polish (C1), practical experience using AI-powered assistants (e.g. Claude Code, GitHub Copilot, Cursor) to improve productivity, quality, or decision-making in software delivery. immediate availability or a short notice period is preferred. Work from the European Union region and a work permit are required. 🟣 Nice to have: experience applying GenAI in a more structured way within the SDLC, including defined workflows, prompt patterns, or tool integrations embedded into daily work, interest in and familiarity with emerging AI-driven practices (e.g. agent-based workflows, automation patterns, AI-augmented development), with a willingness to explore and experiment beyond standard approaches. 🟣 Recruitment Process: CV review – HR call – Technical Interview – Client Interview – Decision 🎁 Benefits 🎁 ✍ Development: development budgets of up to 6,800 PLN, we fund certifications e.g.: AWS, Azure, access to Udemy, O'Reilly (formerly Safari Books Online) and more, events and technology conferences, technology Guilds, internal training, Xebia Upskill. 🩺 We take care of your health: private medical healthcare, multiSport card - we subsidise a MultiSport card, mental Health Support. 🤸‍♂️ We are flexible: B2B or employment contract, contract for an indefinite period.

🏢 Summary: Staff Engineer role focused on leading the design, evolution, and reliability of a high-scale distributed backend platform that generates and distributes real-time customer offers. The position combines deep hands-on backend engineering with architectural leadership in event-driven systems. It emphasizes scalability, performance, observability, and operational excellence in a complex production environment. 🗂️ Requirements: Experience owning complex backend systems end-to-end in scalable production environments, Proven experience designing and operating distributed systems, Strong backend engineering expertise in Java, Solid understanding of JVM performance, Hands-on experience with Apache Kafka, Hands-on experience with Spring Boot and/or Vert.x, Hands-on experience with Redis, Hands-on experience with OpenSearch or Elasticsearch, Experience with observability tools such as Datadog, Grafana, or Kibana, Strong system design skills in event-driven and asynchronous architectures, Knowledge of concurrency and non-blocking system design, Experience with scalability, resiliency, and fault-tolerance strategies, Experience debugging production incidents in distributed environments 📃 Skills: Java, JVM, Kafka, Spring, Vert.x, Redis, OpenSearch, Elasticsearch, Datadog, Grafana, Kibana, Kubernetes 🏢 Description: ABOUT THE ROLE We are looking for a passionate and highly experienced Staff Backend Engineer to help lead the design, development, reliability, and evolution of a complex distributed backend platform. This role is ideal for someone who enjoys going deep into understanding both the technical and business context behind problems, not just implementing solutions mechanically. We value engineers who are curious, proactive, and driven by learning - people who enjoy experimenting, challenging assumptions, and troubleshooting complex systems until the root cause is fully understood. As a Staff Backend Engineer, you will provide technical leadership across architecture, engineering practices, and platform evolution while remaining hands-on when needed. You will help teams make better technical decisions, raise engineering standards, simplify complex systems, and create solutions that balance business needs with long-term platform health. We're looking for someone who is comfortable working in ambiguity, treats failure as an opportunity to learn, welcomes constructive feedback, and leads through collaboration, ownership, and execution rather than authority. ABOUT YOUR FUTURE PLATFORM TEAM We build and operate a critical backend platform that generates, validates, and distributes customer-facing offers across multiple markets in real time. The system sits at the intersection of pricing, configuration, compliance, and localization - where milliseconds matter, correctness is non-negotiable, and small mistakes can have large-scale impact. Our systems apply complex configuration and licensing rules, handle market and event-level blocking, manage multi-language localization, and transform raw pricing data into customer-ready offers consumed across the ecosystem. We process high-throughput event streams, deal with constantly changing data, and solve problems that require both strong engineering fundamentals and deep domain understanding. Success means no incorrect or missing offers in production, near real-time reflection of pricing and configuration changes, fully compliant offers across jurisdictions, and seamless multi-language experiences for customers. Our ecosystem is built around: Event streaming and backbone: Apache Kafka Backend services: Java 23+ with Spring Boot and Vert.x (we are continuously evolving toward highly reactive, asynchronous, and event-driven architecture) State and performance optimization: Redis Search and analytics: OpenSearch / Elasticsearch Observability and operations: Datadog, Grafana, Kibana Runtime and scalability: Kubernetes-based containerized infrastructure We are actively evolving our platform toward more reactive, asynchronous, and event-driven architectures, making this an exciting environment for engineers who enjoy distributed systems, performance, concurrency, and real-time data processing challenges. WHAT YOU'LL DO Technical Leadership Leading architecture and design discussions for scalable, resilient distributed systems Collaborating with Architects and senior engineers to define solution approaches and evaluate new technologies through spikes and PoCs Improving and simplifying existing system designs while maintaining high engineering standards for performance, correctness, and maintainability Maintaining a strong engineering bar across quality, scalability, and maintainability Platform Reliability & Engineering Excellence Proactively identifying scalability, reliability, and performance risks across the platform Leading debugging and root cause analysis for complex production incidents Improving observability, monitoring, alerting, and operational readiness Driving technical debt reduction and continuous platform improvement Promoting best practices across event-driven systems, resiliency patterns, performance optimization, testing, automation, and CI/CD Team Enablement & Collaboration Supporting day-to-day technical coordination within the team and contributing to incident handling and engineering discussions Mentoring engineers through design reviews, code reviews, and hands-on technical guidance Supporting cross-team collaboration and helping troubleshoot integration and platform issues Encouraging a culture of collaboration, clarity, and shared ownership Actively participating in engineering communication channels and helping unblock others Delivery & Execution Working closely with Product, Engineering Managers, and Architects to translate ideas into executable technical solutions Helping define and break down EPICs and technical initiatives in Jira Driving clarity in ambiguous or complex technical initiative Ensuring alignment between short-term delivery needs and long-term platform evolution WHAT WE'RE LOOKING FOR Required Experience: Experience owning complex backend systems end-to-end in scalable production environments Proven experience designing and operating distributed systems Strong backend engineering expertise in Java, with solid understanding of JVM performance Hands-on experience with: Apache Kafka and event-driven architectures Spring Boot and/or Vert.x Redis for low-latency and stateful use cases OpenSearch / Elasticsearch for querying and analytics Observability tools such as Datadog, Grafana, or Kibana Strong system design skills, including: Event-driven and asynchronous architectures Concurrency and non-blocking system design Scalability, resiliency, and fault-tolerance strategies Evaluating trade-offs between latency, throughput, and consistency Experience debugging production incidents in distributed environments Strong communication skills and ability to influence technical decisions across teams Proactive mindset with strong ownership and accountability Comfortable working in complex, fast-paced engineering environments Collaborative approach and willingness to support and mentor others Nice to Have: Kubernetes and cloud-native infrastructure experience Experience building internal platforms or shared engineering frameworks SRE mindset and operational excellence practices Experience with real-time or high-throughput data systems Experience leading cross-team technical initiatives WHAT SUCCESS LOOKS LIKE Teams rely on you for technical direction and practical problem-solving The platform becomes more reliable, scalable, and easier to operate over time Production incidents decrease due to proactive engineering and improved system design Cross-team dependencies are better coordinated and easier to manage Engineering quality and consistency improve across services and squads Engineers grow technically through your mentorship and guidance WHAT WE OFFER Competitive salary aligned with your experience, expertise, and impact A collaborative, inclusive, and fast-paced engineering environment where ideas are welcomed, ownership is encouraged, and continuous learning is valued Hybrid work policy 4 weeks of Workation (T&C apply) Benefits package - 800 PLN net (B2B)/gross (UOP) monthly with access to the cafeteria platform (private medical care, insurances, sports card) Training budget ICAS assistance program that can provide help and guidance during challenging moments. Our office provides complimentary snacks and drinks; on Mondays, we serve complimentary breakfast. Team and office social events throughout the year Free parking for bicycles and motorcycles Free gym in the building Equipment: MacBook Pro + smartphone (iPhone 16/17 or Samsung Galaxy S25)

🏢 Summary: Engineering role focused on maintaining and improving a production Ruby on Rails system in a sustainability-focused product. The position involves triaging client requests, resolving full-stack production incidents, and collaborating with Product and Customer teams in a dynamic, ticket-driven environment. It emphasizes system reliability, root-cause analysis, and continuous improvement of support processes. 🗂️ Requirements: 5+ years of Ruby on Rails experience, Strong experience with production systems, Ability to debug and perform root-cause analysis, Full-stack capability (backend, integrations, basic infrastructure), Experience handling incidents and production issues, Ability to work in on-call rotations, Experience with CI/CD pipelines, Experience with cloud infrastructure, Strong understanding of relational databases 📃 Skills: Ruby, Rails, Hotwire, Turbo, AWS, Docker, PostgreSQL, Datadog, GitHub, CI/CD, Jira, Slack 🏢 Description: Do you care about making an impact on sustainability? Help consumers and brands better understand their environmental impact and make better choices for the planet! 🌎 This role sits at the intersection of engineering, product, and client interaction. You will work in a dynamic, ticket-driven environment where priorities shift based on real usage, incidents, and business needs. What you’ll do: Handle and triage incoming client requests (Jira, Slack, calls) Investigate and resolve incidents across the full stack (backend, frontend, integrations) Work on production issues - from quick fixes to deeper root-cause analysis Collaborate with Product and Customer teams to understand and address user needs Implement small improvements and fixes independently Contribute to improving incident handling and support processes Participate in on-call rotations and ensure system reliability Provide technical input on feasibility and impact of client requests Tech stack: Ruby on Rails (monolith) Hotwire / Turbo AWS Docker GitHub Actions (CI/CD) PostgreSQL Datadog What are we looking for? 🎯 5+ years of experience with Ruby on Rails Strong experience working with production systems Excellent debugging and problem-solving skills Ability to work across the stack (backend, integrations, basic infra) Strong ownership and communication skills Comfortable working in a dynamic, reactive environment Nice-to-have: Experience in support / maintenance / -like roles Familiarity with monitoring tools (e.g. Datadog) Experience with AWS What you get: Real impact on system stability and client experience High ownership and autonomy in decision-making Exposure to a wide range of technical challenges Close collaboration with product and client-facing teams Opportunity to deeply understand how the system behaves in production A role suited for engineers who enjoy problem-solving over repetitive feature delivery It is not the best fit if: You are looking for a purely feature-driven role with long-term, predictable roadmaps You get frustrated by frequent context switching or changing priorities You expect a clean, well-structured codebase with minimal technical debt Sounds like a fit? Let’s talk! 🚀