Senior Full Stack Engineer (.NET, Java, Kotlin, Angular)

🏢 Summary: Full-time Senior Backend Developer role building a modern, large-scale enterprise platform for a global manufacturing customer. The position focuses on Node.js/TypeScript backend services, REST APIs, enterprise integrations, database design, and secure, scalable application delivery, with planned work through December 2026 and a possible extension to February 2027. 🗂️ Requirements: 7+ years of software development experience, 5+ years of Node.js backend development experience, TypeScript and JavaScript proficiency, RESTful API design and development knowledge, Enterprise-scale web application development experience, Software architecture and design patterns knowledge, Relational database experience, Secure coding and application security knowledge, Agile development experience, Advanced English, Availability for business trips to Basel, Switzerland 📃 Skills: Node.js, TypeScript, JavaScript, REST, PostgreSQL, SQL, Agile 🏢 Description: Svitla Systems Inc. is looking for a Senior Backend Developer (Node.js) for a full-time position (40 hours per week) in Europe . Our client is a leading multinational company in the building materials industry. You'll join the implementation of a large-scale enterprise web application for a global manufacturing customer. The project focuses on developing and implementing a modern enterprise platform that will replace an existing business application used across multiple countries. The backend solution will be built using modern technologies and integrated with various enterprise systems to support business-critical processes. The project's planned end date is December 18, 2026, with a possible extension to February 01, 2027. Requirements 7+ years of experience in software development. 5+ years of experience developing backend applications using Node.js. Strong knowledge of TypeScript and JavaScript. Understanding of designing and developing RESTful APIs. Experience with enterprise-scale web application development. In-depth understanding of software architecture principles and design patterns. Knowledge of relational databases (PostgreSQL, SQL Server, or similar). Understanding of secure coding practices and application security principles. Experience working in Agile software development environments. Strong analytical and problem-solving skills. Advanced English. Availability for business trips to Basel, Switzerland, during key project phases (Kick-off, end of Concept Phase, and Go-Live readiness review). Responsibilities Develop scalable backend services using Node.js and TypeScript. Implement RESTful APIs and backend business logic for enterprise web applications. Collaborate with architects to define technical solutions and application architecture. Participate in technical design sessions and solution discussions. Integrate backend services with internal and third-party enterprise systems. Design and optimize database structures, queries, and data models. Ensure application performance, scalability, reliability, and security. Write clean, maintainable, and well-tested code following engineering best practices. Participate in code reviews. Collaborate closely with Front End Developers, QA Engineers, Business Analysts, and DevOps Engineers. Participate in Agile ceremonies including sprint planning, daily stand-ups, reviews, and retrospectives. We offer US and EU projects based on advanced technologies. Competitive compensation based on skills and experience. Regular performance appraisals to support your growth. Flexibility in workspace, either remote or our welcoming office. Bonuses for article writing, public talks, and other activities. Generous time off, including vacation, national holidays, sick leaves, and family days. Personalized learning programs tailored to your interests and skill development. Free tech webinars and meetups organized by Svitla. Regular corporate online activities. Awesome team and a friendly, supportive community!

🏢 Summary: Full-time Senior Java Engineer role supporting a large-scale digital marketing platform’s core backend, messaging, queues, and REST APIs. The position follows EST hours and includes a 24/7 on-call rotation every three weeks, including weekends. 🗂️ Requirements: 6+ years of commercial Java engineering experience, 6+ years developing large-scale applications, Experience with distributed systems, Experience with multithreading, Expert SQL knowledge, Strong Kubernetes experience, Knowledge of Cassandra, Knowledge of AWS SQS, S3, CloudFormation, and Lambda, Knowledge of Jenkins, Experience with OTEL and Grafana, Familiarity with AI agents, Upper-intermediate English or higher, Availability for EST working hours, Participation in 24/7 on-call rotation, including weekends 📃 Skills: Java, SQL, Kubernetes, Cassandra, AWS, SQS, S3, CloudFormation, Lambda, Jenkins, OTEL, Grafana, AI 🏢 Description: The Opportunity Svitla Systems Inc. is looking for a Senior Java Engineer for a full-time position (40 hours per week) in Europe. Our client is a digital marketing company that offers email marketing, social media marketing, event marketing, and online survey tools to help organizations expand their businesses by fostering stronger customer relationships. General info on the Big Delivery Team: handles all back-end systems, message processing, queuing, REST API apps, and messaging apps. Sometimes the whole team can handle incidents in the prod environment, and developer engagement will be needed. On-call rotation: once every 3 weeks; availability outside US business hours; 24/7 on-call, so weekends are also covered. Working hours: EST working hours (from 9 am EST). Requirements: 6+ years of commercial experience in developing large-scale applications. Proven experience in distributed systems and multi-threading. 6+years of commercial experience as a Java Engineer with successful project implementations. Expert knowledge of SQL. Strong experience with Kubernetes. Knowledge of Cassandra. Strong understanding of the following AWS services: SQS, S3, CloudFormation, Lambda. Knowledge of  Jenkins. Experience with observability tools such as OTEL and Grafana. Familiarity with AI; understanding of how to run and work with agents. Upper-intermediate English or higher. Nice to have: Some experience with DevOps and/or SRE, since they're expected to do a bit of everything here. Domain knowledge of email, SMS, push, etc. Experience with Quarkus and Ruby. Knowledge of RabbitMQ and ZooKeeper. Knowledge of AWS EKS and CloudWatch. Experience with CI/CD: Argo. Experience with HyperDX. Familiarity with JUnit, RSpec. Familiarity with JavaScript. Familiarity with DynamoDB. Responsibilities: Perform the development of the core back-end platform that supports multiple apps in the customer’s ecosystem. Participate in on-call rotations to ensure stable infrastructure support. Provide development of RESTful APIs. Be actively involved in team meetings and product discussions.

🏢 Summary: Full-time Senior .NET Developer role focused equally on maintaining legacy .NET Framework 4.8 backend systems and delivering AI/ML-powered product features. The position involves integrating AI APIs, owning services throughout their lifecycle, and collaborating asynchronously with a global team during 15:00–18:00 CET overlap hours. Flexible hybrid work is available, with occasional visits to the Gdańsk office. 🗂️ Requirements: 5+ years of professional .NET/C# experience, Experience with .NET Framework 4.8 production systems, Software architecture knowledge, Microservices and REST API knowledge, Async programming experience, AI/ML model or API integration experience, Cloud platform experience, Written communication and asynchronous collaboration skills, Availability for 15:00–18:00 CET US meeting overlap, Independent end-to-end problem ownership 📃 Skills: .NET, C#, Azure, Microservices, REST, AI, ML 🏢 Description: Svitla Systems Inc. is looking for a Senior .NET Developer (AI/ML Integration) for a full-time position (40 hours per week) in Poland. Our client is an AI-driven SaaS company delivering a unified platform for retailers. We're looking for a Senior .NET Developer who combines strong backend engineering skills with hands-on experience building AI/ML-powered features. You'll split your time evenly between core .NET development — including maintaining and evolving our legacy systems — and integrating AI capabilities into our products. AI isn't a "nice to have" here; it's a core part of the job. This role works across a globally distributed team spanning India and both US coasts, so comfort with asynchronous collaboration and overlapping across time zones is important. The role offers a flexible hybrid format, with occasional visits to our Gdańsk office approximately 1–2 times per month. Requirements: 5+ years of professional experience with .NET / C#, including working with .NET Framework 4.8 in legacy production systems. Solid understanding of software architecture (microservices, REST APIs, async patterns, etc.). Experience integrating AI/ML models or APIs into applications. Comfortable working across legacy (.NET Framework). Experience with cloud platforms (Azure preferred, given the .NET stack). Strong written communication and async collaboration skills, given the distributed, multi-time-zone team, working evening hours to accommodate meetings with the US: 15-18CET. Comfortable working independently and owning problems end-to-end. Nice to have: Python, for ML/data workflows alongside .NET. Node.js / React, for full-stack or frontend collaboration. Docker / Kubernetes, for containerization and deployment. Strong grasp of SOLID principles and clean architecture practices. Experience with TDD (Test-Driven Development). Familiarity with prompt engineering. Experience modernizing legacy .NET Framework apps (e.g., migration paths to .NET Core). Understanding of CI/CD pipelines. Responsibilities: Design, build, and maintain backend services using .NET Framework 4.8 (legacy). Architect and implement AI/ML-powered features (LLM integrations, RAG pipelines, recommendation systems, or similar). Integrate with AI APIs and platforms (e.g., OpenAI, Anthropic, Azure AI, or similar). Support existing .NET Framework 4.8 legacy applications. Own technical decisions across the full lifecycle: design, development, testing, deployment, monitoring. Collaborate with product and data teams to translate designs into real user-facing features. Coordinate effectively with teammates across India, East Coast, and West Coast time zones. Mentor other engineers and contribute to technical direction. We offer: US and EU projects based on advanced technologies. Competitive compensation based on skills and experience. Regular performance appraisals to support your growth. Flexibility in the workspace, either remote or in our welcoming office. Comprehensive medical insurance after one month. MultiSport card with access to 2500 sports facilities all over Poland Bonuses for recommendations of new employees. Bonuses for article writing, public talks, and other activities. 15 vacation days, 10 national holidays, 10 sick leaves, and family days off. Personalized learning program tailored to your interests and skill development. Free tech webinars and meetups organized by Svitla. Welcome and anniversary presents, gifts for children, and more. Regular corporate events and meetups. Awesome team, friendly and supportive community! Ref # 5299

🏢 Summary: Full-time Senior Full Stack Developer role focused on building React and TypeScript interfaces, BFF services, and integrations with APIs, LLMs, and streaming endpoints. The position covers scalable frontend architecture, performance and resilience, and delivery of product features from prototype to production, with office work expected 2–3 days per week. 🗂️ Requirements: Strong hands-on TypeScript experience, Several years of software engineering experience, Strong React and modern frontend tooling experience, Frontend unit and integration testing experience, API design and development with NestJS and Node.js, Understanding of server-side rendering, Server Components, CDN strategies, and caching, Software architecture, clean code, and system design knowledge, Ability to work effectively amid uncertainty, Docker, Git, CI/CD, and Azure experience 📃 Skills: TypeScript, React, NestJS, Node.js, Docker, Git, CI/CD, Azure, Testing, SSR, CDN, Caching 🏢 Description: Role overview Svitla Systems Inc. is looking for a Senior Full Stack Developer for a full-time position (40 hours per week) in Kraków, Poland. Our client is a British wholesale distributor. You will be responsible for building user interfaces with TypeScript and React, developing and maintaining BFF services, integrating APIs and LLM services, designing scalable frontend architecture, optimizing application performance and user experience, implementing error handling and resilience patterns, and collaborating with product and engineering teams to deliver features from prototype to production. Office work is expected 2-3 days per week. Responsibilities Building user interfaces using TypeScript and React. Building and maintaining Backend for Frontend (BFF) services to orchestrate API calls and shape data for user interface needs. Integrating APIs, LLM services, and streaming endpoints to deliver product features. Designing and implementing scalable and maintainable frontend architecture. Ensuring performance, responsiveness, and optimal user experience across the application. Implementing error handling, loading states, and resilience patterns for distributed systems. Collaborating with product and engineering teams to bring concepts from prototype to production. Requirements Strong hands-on experience with TypeScript development. Several years of experience in software engineering, ideally with a strong focus on React and modern frontend development tools. Experience with frontend testing, including unit and integration testing. API design and development experience using NestJS and Node.js. Understanding of server-side rendering, Server Components, CDN strategies, and caching. Solid understanding of software architecture, clean code, and system design. Ability to work effectively in environments with a high degree of uncertainty and take a pragmatic, solution-oriented approach to problem-solving. Experience with Docker, Git, CI/CD, and Azure. Nice to Have Knowledge of GraphQL APIs. Experience with state management libraries (e.g. Zustand, React Query). Familiarity with Python, particularly in the context of working with backend services or AI-powered systems. Experience building data-intensive or real-time user interfaces. Familiarity with designing user experiences for AI-powered features or non-deterministic outputs. We offer US and EU projects based on advanced technologies. Competitive compensation based on skills and experience. Regular performance appraisals to support your growth. Flexibility in the workspace, either remote or in our welcoming office. Comprehensive medical insurance after one month. MultiSport card with access to 2500 sports facilities all over Poland Bonuses for recommendations of new employees. Bonuses for article writing, public talks, and other activities. 15 vacation days, 10 national holidays, 10 sick leaves, and family days off. Personalized learning program tailored to your interests and skill development. Free tech webinars and meetups organized by Svitla. Welcome and anniversary presents, gifts for children, and more. Regular corporate events and meetups. Awesome team, friendly and supportive community!

🏢 Summary: Oferta długofalowej współpracy dla Senior Full Stack Developera przy rozwoju nowoczesnych aplikacji biznesowych w międzynarodowym środowisku. Rola obejmuje backend w Java i Spring Boot oraz frontend SPA w Angularze, z wykorzystaniem mikroserwisów, Kafka, Oracle SQL i praktyk CI/CD. Praca hybrydowa w Warszawie w modelu 60/40, ze stawką 140–160 PLN netto/h + VAT. 🗂️ Requirements: Minimum 10 lat komercyjnego doświadczenia w tworzeniu oprogramowania, Aktualne doświadczenie full stack: backend i frontend, Bardzo dobra znajomość Java 17–21, Doświadczenie ze Spring Boot 3.x i architekturą mikroserwisową, Praktyczna znajomość Kafka i architektury event-driven lub messaging, Bardzo dobra znajomość SQL w środowisku Oracle, Doświadczenie lub dobra znajomość Redis, Doświadczenie z Domain-Driven Design, Praktyczne doświadczenie z Angular, TypeScript i aplikacjami SPA, Znajomość architektury Angular i dobrych praktyk frontendowych, Bardzo dobra znajomość bezpieczeństwa aplikacji webowych, OAuth2 i OIDC, Znajomość Git oraz doświadczenie z CI/CD, szczególnie GitLab CI, Znajomość Jira i Confluence, Język angielski na poziomie B2/C1, Gotowość do pracy hybrydowej: 60% czasu z biura klienta w Warszawie, Samodzielność, analityczne podejście i dobra komunikacja 📃 Skills: Java, Spring, Angular, TypeScript, Kafka, Oracle, SQL, Redis, Git, GitLab, Jira, Confluence, OAuth2, OIDC, DDD, CI/CD 🏢 Description: Be in IT to firma rekrutacyjna, wyspecjalizowana w poszukiwaniu Specjalistów z branży technologii informatycznych. Obecnie, dla naszego klienta, poszukujemy osoby na stanowisko Senior Full Stack Developer (Java + Angular). Zakres obowiązków: Długofalowa współpraca z międzynarodową, topową firmą consultingową, świadcząca usługi IT dla dużych i średnich firm z różnorodnych sektorów jak automotive, healthcare, finanse, bankowość czy produkcja. Projektowanie, rozwój i utrzymanie nowoczesnych aplikacji fullstack wspierających kluczowe procesy biznesowe. Rozwój backendu w Java 17–21 oraz Spring Boot 3.x, ze szczególnym naciskiem na architekturę mikroserwisową. Tworzenie i rozwój aplikacji typu Single Page Application z wykorzystaniem Angular i TypeScript. Integracja systemów w oparciu o architekturę event-driven oraz platformę Kafka. Praca z bazami danych Oracle SQL oraz optymalizacja istniejących rozwiązań. Tworzenie bezpiecznego, skalowalnego, testowalnego i łatwego w utrzymaniu kodu. Udział w projektowaniu rozwiązań, analizach przedprojektowych oraz podejmowaniu decyzji technicznych. Współpraca z interesariuszami biznesowymi i technicznymi w środowisku międzynarodowym. Implementacja, utrzymanie i rozwój testów automatycznych oraz pipeline’ów CI/CD. Dbanie o bezpieczeństwo aplikacji, w tym obsługę identity management, OAuth2 oraz OIDC. Utrzymywanie i aktualizacja dokumentacji technicznej. Udział w wymianie wiedzy i promowaniu dobrych praktyk developerskich w zespołach wewnętrznych i zewnętrznych. Oczekujemy: Minimum 10 lat doświadczenia komercyjnego w rozwoju oprogramowania. Praktycznego doświadczenia fullstack -  wymagane aktualne doświadczenie na backendzie i frontendzie. Bardzo dobrej znajomości Java 17–21, mile widziane doświadczenie z nowszymi wersjami. Doświadczenia ze Spring Boot 3.x oraz architekturą mikroserwisową. Praktycznej znajomości Kafka oraz systemów opartych o architekturę event-driven lub messaging. Bardzo dobrej znajomości SQL, szczególnie w środowisku Oracle. Doświadczenia lub dobrej znajomości Redis. Doświadczenia z Domain-Driven Design. Praktycznego doświadczenia z Angular, TypeScript oraz aplikacjami typu SPA. Znajomości dobrych praktyk frontendowych, architektury aplikacji Angular oraz zasad utrzymywalności kodu. Bardzo dobrej znajomości zagadnień bezpieczeństwa aplikacji webowych, praktycznej znajomości OAuth2 oraz OIDC. Znajomości Git oraz doświadczenia z CI/CD, szczególnie GitLab CI. Znajomości narzędzi Jira i Confluence. Znajomości języka angielskiego na poziomie B2 lub C1, umożliwiającej codzienną pracę w międzynarodowym środowisku. Gotowości do pracy hybrydowej - 60% czasu z biura klienta w Warszawie na Mokotowie. Samodzielności, analitycznego podejścia, dobrej komunikacji oraz nastawienia na współpracę. Mile widziane: Doświadczenie z Node.js. Znajomość Maven. Doświadczenie z Docker i Kubernetes. Znajomość Webpack. Doświadczenie z platformami identity management. Znajomość zasad OWASP lub certyfikacje w obszarze bezpieczeństwa. Oferujemy: Długofalowa współpraca z wynagrodzeniem w przedziale 140-160 PLN netto/godz. + VAT. Możliwość pracy w projekcie z nowoczesnym stosem: Java 17–21, Spring Boot 3.x, Kafka, Angular, TypeScript, Oracle SQL, Redis, GitLab CI (zero legacy). Udział w projektowaniu rozwiązań, analizach technicznych i podejmowaniu realnych decyzji architektonicznych. Wsparcie przy zakładaniu i prowadzeniu działalności gospodarczej, dla osób bez takiego doświadczenia. Sprawny proces rekrutacyjny - dwie rozmowy techniczne z managerami, online (każda maksymalnie po godzinie). Współpraca hybrydowa z biura w Warszawie w modelu 60/40 (w skali miesiąca). Benefity - prywatna opieka medyczna, karta Multisport. Nowoczesny sprzęt zapewniany przez firmę, wraz z softem i konfiguracją.