Senior .Net Backend Engineer

🏢 Summary: Backend Engineer role focused on building AI-centric digital products for employees and HR stakeholders. The position involves Java/Spring Boot microservices development, API and cloud integration, production observability, and maintaining secure, reliable solutions in a hybrid Kraków or Wrocław work model. 🗂️ Requirements: Strong Java and Spring Boot experience, Spring Batch and Spring Cloud experience, Microservices development experience, REST API and GraphQL schema design proficiency, NoSQL data modelling experience, Data streaming experience, OAuth 2.0 and Microsoft Entra ID knowledge, Azure Cloud Services familiarity, English communication skills, Agile collaboration experience, Commitment to quality, maintainability and documentation 📃 Skills: Java, SpringBoot, SpringBatch, SpringCloud, Microservices, REST, GraphQL, NoSQL, CosmosDB, Kafka, OAuth2, EntraID, Azure, AppServices, AzureMonitor, APIManagement, Observability, Testing 🏢 Description: Role summary We are looking for a Backend Engineer to design, develop, and continuously improve intelligent digital products and services that support employees and HR stakeholders, with AI at the core. 📍 Work mode: Hybrid (2–3 days/week) — Kraków or Wrocław office Primary skills Java, Spring Boot, microservices, REST APIs Key responsibilities: Design, develop, and continuously improve intelligent digital products and services that support employees and HR stakeholders, with AI at the core. Apply modern engineering practices, from analyzing user needs and developing new features to automated testing, deployment, and observability. Ensure quality, security, reliability, and compliance by applying digital principles and implementing functional and non-functional requirements. Build observability into solutions, monitor production health, help resolve incidents, and remediate root causes of risks and issues. Advocate for user and stakeholder needs, ensuring AI solutions are explainable, ethical, and human-centric. Share knowledge openly, contribute to hiring and onboarding, and help shape a collaborative, forward-thinking engineering culture. Required skills and experience: Strong experience in Java and Spring Boot, including Spring Batch and Spring Cloud, and building microservices. Proficiency in REST API and GraphQL schema design. Experience with NoSQL data modelling, such as Azure Cosmos DB ; data streaming, such as Confluent Kafka; and authentication/authorization protocols, including OAuth 2.0 and Microsoft Entra ID. Familiarity with Azure Cloud Services , including App Services, Azure Monitor, and API Management. Collaborative communication skills: able to express ideas clearly in English and adapt technical content for diverse audiences while working closely with product managers, designers, and engineers in agile settings. Strong commitment to quality, maintainability, documentation, and continuous learning. AI-related skills, such as Spring AI or LangChain, are a strong plus. Benefits ✅ Stable long-term cooperation with opportunity for extension Opportunity to work with modern technologies in an international environment Professional growth and continuous development opportunities Participation in challenging and impactful projects 📩 If you’re interested and meet the qualifications, please send your CV at alina.pchelnikova@dcvtechnologies.co.uk

🏢 Summary: Join an early-stage product team to design and deliver scalable, high-volume backend systems using Node.js, TypeScript, and AWS. The role offers end-to-end ownership, influence over architecture and engineering practices, and mentoring responsibilities in a hybrid Kraków setup. 🗂️ Requirements: 5+ years of production software development with Node.js and TypeScript, Practical AWS knowledge, Distributed systems design knowledge, Scalability knowledge, Event-driven architecture experience, Automated testing experience, Independent problem-solving ability, English communication skills, Ability to work in an evolving, fast-paced environment 📃 Skills: Node.js, TypeScript, AWS, Lambda, ECS, S3, RDS, Jest, Vitest, Playwright 🏢 Description: Senior Backend Engineer: Node.js & AWS Location: Kraków, Poland Working model: Hybrid Contract: Employment agreement or B2B Build high-scale systems from the beginning We’re hiring an experienced backend engineer to join a growing international technology business as it expands its engineering presence in Kraków. This is an opportunity to help create a new product rather than inherit a finished roadmap. You’ll influence early technical decisions, build systems designed for demanding workloads, and take meaningful ownership from architecture through production. The company develops robust data infrastructure used by organizations operating in complex, high-stakes environments. Its technology processes large volumes of information and supports products where speed, availability, and accuracy genuinely matter. If you enjoy solving difficult engineering problems, making pragmatic architectural decisions, and seeing your work reach production, this role offers plenty of room to make an impact. What you’ll be doing Design and deliver scalable backend services with Node.js and TypeScript. Build APIs and asynchronous, event-driven workflows in AWS. Engineer reliable systems capable of supporting intensive, high-volume workloads. Own features throughout their lifecycle, from technical discovery and design to deployment and ongoing improvement. Help establish the architecture and engineering practices of a new product. Partner with product specialists and engineers across multiple disciplines. Support other developers through mentoring, thoughtful reviews, and knowledge sharing. Strengthen standards around testing, security, maintainability, and operational reliability. Respond constructively as requirements evolve and new technical challenges emerge. What we’re looking for At least five years of professional experience building production software with Node.js and TypeScript. Strong practical knowledge of AWS. Experience with services such as Lambda, ECS, S3, or RDS is especially relevant. A solid understanding of distributed system design, scalability, and event-driven architecture. Experience using modern automated testing tools such as Jest, Vitest, or Playwright. The confidence to investigate unfamiliar problems and move work forward independently. Clear English communication skills. Comfort working in an energetic environment where priorities and products continue to evolve. Additional experience we’d value You don’t need to bring everything on this list, but any of the following would be useful: Go development. Distributed platforms or messaging-based systems. Large language models or contemporary AI development tools. React. Relational and non-relational databases. Docker and Kubernetes. CI/CD pipelines and modern delivery practices. Why consider this opportunity? Join at an early stage and help shape a product’s technical direction. Work on challenging systems where performance and reliability are fundamental. Take genuine ownership without unnecessary layers of decision-making. Become part of a new engineering group in Kraków with room to influence how it develops. Collaborate in an international, English-speaking environment. Choose between an employment contract and a B2B arrangement. Work within a hybrid model in Kraków. Join a profitable, expanding business focused on sustainable long-term growth.

🏢 Summary: Senior Frontend Engineer role building enterprise AI interfaces and production Next.js applications with complex state, real-time functionality, and scalable frontend architecture. The position is fully on-site in Warsaw city centre, five days per week, with responsibility for UI quality, performance, accessibility, and enterprise-grade features. 🗂️ Requirements: Work on-site in Warsaw city centre 5 days per week, 5+ years of frontend development experience, 3+ years of React and TypeScript experience, Production Next.js experience, App Router and Server Components expertise, SSR, SSG and CSR knowledge, Complex state-management experience, Real-time and multi-tenant application experience, AI or LLM interface experience, Frontend performance and Core Web Vitals expertise, Accessibility, localization and frontend security knowledge, Experience handling sensitive data, Experience using AI coding assistants 📃 Skills: React, TypeScript, Next.js, SSR, SSG, CSR, LLM, AI, CoreWebVitals, Accessibility, Localization, Security, Claude, Codex, Copilot 🏢 Description: Please note: This role requires working from our office in Warsaw city centre 5 days a week . This is a fully on-site position , and remote or hybrid work is not available . About us We believe that businesses are moving toward AI-powered work, and we are building a platform for this future. Many AI agents cannot handle complex business tasks. We created a platform that organizes company policies, workflows, and business knowledge into one AI data model. This helps AI agents make accurate decisions and deliver reliable results at scale. We already work with well-known enterprise customers such as Glovo, Nespresso, and HelloFresh. Our platform supports thousands of users and processes real production data. Customers trust us with important business knowledge because we provide a secure and reliable solution with SOC2, HIPAA-ready security practices, and strong integrations. Job description We are looking for a Senior Frontend Engineer who enjoys building high-quality user interfaces for enterprise AI products. In this role, you will design and build important frontend features, solve complex UI problems, and improve the user experience over time. You will take ownership of frontend architecture and help build production Next.js applications with complex state management, real-time AI features, and enterprise functionality. The position is based in Warsaw and requires working from the office. Responsibilities Design and build production Next.js applications that support complex state, high traffic, and real-time AI features. Create user interfaces for AI-powered tools, including streaming AI responses, semantic search, knowledge graphs, and AI agents. Build and improve our component library and design system to keep the user experience consistent, accessible, and reusable. Deliver enterprise features such as localization, accessibility, browser compatibility, and security. Monitor applications after release, improve performance, reduce bundle size, track Core Web Vitals, and help systems scale. Maintain high engineering standards through code reviews, testing, and mentoring other developers. Requirements More than 5 years of frontend development experience, including at least 3 years working with React and modern TypeScript. Strong experience building production applications with Next.js, including App Router, Server Components, and understanding SSR, SSG, and CSR. Experience managing complex application state, including real-time updates, optimistic UI, multi-tenant systems, and large amounts of data. Experience building AI or LLM-based interfaces such as chat applications, streaming responses, or semantic search. Strong knowledge of frontend performance and experience improving Core Web Vitals in large applications. Good understanding of accessibility, localization, security, and enterprise application standards. A security-focused approach and experience working with sensitive data. Strong product thinking and the ability to improve user experience without waiting for detailed designs. Experience using AI coding assistants as part of your daily development work. Good written and spoken communication skills and the ability to explain technical decisions clearly. Nice to have Experience with React Flow, Highcharts, or other data visualization libraries. Experience building vector search, RAG, generative AI, or semantic search interfaces. Basic knowledge of Node.js or Python to understand backend code and APIs. Experience contributing to design systems or open-source UI libraries. What we offer B2B contract and company stock options. MacBook Pro. Modern technology stack and the opportunity to contribute to open-source projects. An AI-focused development environment with tools such as Claude Code, OpenAI Codex, and GitHub Copilot. Our values Our leadership team has strong experience in AI, knowledge management, and enterprise SaaS. We have received more than $60 million in funding and have been recognized by Gartner as a Cool Vendor. Our work is guided by these values: Quality – We care about excellent work and high standards in everything we build. Momentum – We take initiative, share ideas, and keep moving forward. Accountability – We take responsibility for our work and give honest, respectful feedback. Hard work – We believe success comes from teamwork, dedication, and consistent effort. Learning agility – We stay curious, learn from mistakes, and continue improving. Adapt and thrive – We welcome change and see challenges as opportunities to grow. Win together – We work as one team, communicate openly, and support our shared goals.

🏢 Summary: Long-term remote B2B opportunity for a Senior Frontend Developer to build a secure, real-time incident reporting platform for a European Union institution. The role focuses on micro-frontend architecture, modernization of monolithic applications, performance optimization, and collaboration across multidisciplinary teams. 🗂️ Requirements: University degree in Computer Science, Computer Engineering, Telecommunications, Information Technology, Business Administration and Management, or related discipline, 5+ years of professional frontend development experience, Advanced JavaScript and TypeScript knowledge, Experience with Angular, Experience with SPA and micro-frontend architectures, Experience with .NET and C#, Knowledge of HTML5, Web Components, and browser APIs, Knowledge of web application performance, scalability, and security, Familiarity with cloud environments and container platforms 📃 Skills: JavaScript, TypeScript, Angular, NET, C#, HTML5, WebComponents, SPA, Microfrontends, Microservices, OpenShift, Cloud, Containers, UI/UX 🏢 Description: Currently, for one of our Partners, we are looking for an experienced Senior Frontend Developer (m/f/n) to support a long‑term project delivered for an organization of the European Union based in Warsaw. You will be joining a strategic project for a European institution, linked to security and border control activities. The project aims to develop a new generation of systems capable of reporting and disseminating information on incidents in real time. The solution will implement the new requirements set out in the regulation recently adopted by the European Commission. Tasks: As a Senior Front-End Engineer, you will participate in the definition, design and implementation of the new platform, working closely with multidisciplinary teams to build scalable, secure and high-performance solutions: Design and implement solutions based on micro-frontend architecture. Participate in the transformation of monolithic applications into architectures based on microservices and micro-frontends. Analyse, optimise and improve the performance, scalability and maintainability of applications. Apply security best practices from the design phase (Security by Design). Collaborate with business analysts in defining and validating functional requirements. Work closely with backend and frontend teams to ensure integrated and consistent solutions. Produce high-quality technical documentation. Carry out code reviews and contribute to the continuous improvement of development standards. Support the analysis and design of user interfaces (UI/UX) Requirements: A university degree in Computer Science, Computer Engineering, Telecommunications, Information Technology, Business Administration and Management, or related disciplines. A minimum of 5 years of demonstrable professional experience in front-end development. Advanced knowledge of JavaScript and TypeScript. Solid experience with modern frameworks such as Angular. Practical experience with SPA and micro-frontend architectures. Experience in .NET with C#. In-depth knowledge of HTML5, Web Components and standard browser APIs. Knowledge of performance optimisation, scalability and security in web applications. Familiarity with cloud environments and container platforms (experience with OpenShift will be an advantage). Offer: B2B contract Remote set-up Rate: 165-175 PLN netto + VAT/H

🏢 Summary: Hybrid Backend Developer role focused on building, testing, and maintaining reliable digital banking services in an agile team. The offer combines Java microservices development with ownership of test automation and backend quality, plus occasional business analysis support. Work is hybrid in Warsaw, with a long-term B2B engagement and a rate of up to 160 PLN net plus VAT per hour. 🗂️ Requirements: Java 21+, REST API and microservices development, Spring Boot 3.4 and Spring WebFlux, Hibernate, Git, Maven and Jenkins, Oracle DB, DB2 and SQL, SOLID principles, Test automation, Performance, unit, integration and API testing, Cucumber and WireMock, AI tools 📃 Skills: Java, REST, Microservices, SpringBoot, WebFlux, Hibernate, Git, Maven, Jenkins, Oracle, DB2, SQL, JUnit5, Cucumber, WireMock, AI 🏢 Description: General info: Model of work: hybrid (3 days work from office Warsaw) Type of contract: B2B, long-term cooperations Rate: up to 160 PLN nett + vat/ hour Introduction & Summary Looking for an experienced Backend Developer with a strong focus on testing and a willingness to engage in a blended capability role. This position offers the opportunity to work within an agile team while driving the quality and reliability of digital banking solutions. Main Responsibilities Design, develop, test, and maintain backend services that power our digital banking platforms. Drive backend testing activities within a dedicated agile team, ensuring high-quality, reliable, and scalable solutions. Collaborate closely with business stakeholders to understand requirements and contribute to solution design. Support analysis activities when needed, helping to translate business needs into technical solutions. Leverage AI-powered tools as part of daily development, testing, and delivery practices. Contribute to the full product lifecycle, from technical design and implementation to continuous improvement and operational support. Work collaboratively within a cross-functional agile team to deliver customer-focused digital banking services. Key Requirements Proficient in Java 21+, Rest API, and microservices. Experience with Spring Boot 3.4, Spring WebFlux, Hibernate, Git, Maven, Jenkins, Oracle DB/DB2/SQL, and Junit5. Knowledge of SOLID principles. Proficient in test automation, performance, unit, integration, and API testing. Familiarity with tools like Cucumber and WireMock. Experience in using AI tools. Nice to Have Frontend experience with JavaScript, TypeScript, Angular 2+, and Angular.JS. Familiarity with Playwright and qTest. ISTQB Foundation certification. Experience with Gherkin.

🏢 Summary: B2B opportunity for a Senior .NET Full Stack Software Engineer to modernize and scale asset-management transaction and regulatory reporting platforms. The role focuses on delivering reliable, scalable, high-quality solutions, automating manual processes, and collaborating in a global agile environment. 🗂️ Requirements: Senior .NET development experience, Microsoft Azure expertise, Core .NET technologies knowledge, Database technology knowledge, Ability to translate business requirements into reliable, scalable, high-performance technical solutions, Ability to work in a hybrid model from Wroclaw, B2B contract availability 📃 Skills: Azure, .NET, Databases, DevOps, Agile 🏢 Description: Senior .NET Full Stack Software Engineer (with Azure and DevOps expertise) 📌 Type of contract: B2B 📍 Work mode: Hybrid format from Wroclaw (2/3 days from office) We’re looking for .NET developer in Wroclaw to: drive the modernization and scalability of the client, transaction, and regulatory reporting platforms, within Asset Management technology implement high quality solutions that address business needs and adhere to industry standards drive automation of manual processes to the next level closely collaborate within an agile team and a global agile organization translate high level business requirement into technical requirements addressing reliability, scalability, and performance needs Competencies: Microsoft Azure, Core .NET Technologies, Database Technology Benefits ✅ Stable long-term cooperation with opportunity for extension Opportunity to work with modern technologies in an international environment Professional growth and continuous development opportunities Participation in challenging and impactful projects 📩 If you’re interested and meet the qualifications, please send your CV at alina.pchelnikova@dcvtechnologies.co.uk

🏢 Summary: Hands-on Senior .NET Developer / Technical Lead role focused on building backend APIs for a new customer mobile app and modernizing a large operational platform. The role offers ownership of architecture, integrations, engineering standards, and future backend team development, with compensation of $5,000–$6,000 plus milestone bonuses and relocation support to Warsaw. 🗂️ Requirements: Commercial .NET / C# experience, Production backend systems and API development experience, API design, authentication, authorization, and security knowledge, SQL and database design experience, Third-party and existing business-system integration experience, Legacy application modernization experience, Cloud infrastructure, CI/CD, testing, and production support knowledge, Technical ownership and sound decision-making ability, Strong communication and practical problem-solving skills 📃 Skills: .NET, C#, API, SQL, Authentication, Authorization, Security, CI/CD, Cloud, Testing, Monitoring, Azure, Umbraco, Microservices, IoT, CRM, ERP, CMS 🏢 Description: Senior .NET Developer / Technical Lead One of the largest logistics and storage companies in the region is looking for a Senior .NET Developer / Technical Lead to help build the next generation of its technology platform. This is a hands-on role with significant ownership. You’ll work closely with the leadership and product teams, make important technical decisions, and help modernize a large operational platform used across the business. Your first project: Your immediate priority will be building the backend APIs for a new customer mobile application . Customers will use the app to manage their accounts and rentals, make payments, and access their storage units. You’ll work closely with the mobile team to design the APIs, authentication, permissions, integrations, and backend workflows that make this possible. Beyond the mobile application, you’ll help move the business away from legacy systems and towards a modern, API-driven platform connecting customer applications, operations, payments, access control, reporting, notifications, and other core services. What you’ll do Design and build production APIs and backend services using .NET / C# Work closely with the mobile team on API contracts and backend workflows Take ownership of key backend and architecture decisions Integrate new services with existing systems and SQL databases Help modernize and gradually replace legacy applications Design secure and reliable integrations between business-critical systems Improve testing, monitoring, documentation, and CI/CD practices Help establish development standards as the platform grows Mentor and potentially help build the future backend team What we’re looking for Strong commercial experience with .NET / C# Proven experience building production backend systems and APIs Strong understanding of API design, authentication, authorization, and security Good SQL and database design experience Experience integrating third-party or existing business systems Experience working with or modernizing legacy applications Understanding of cloud infrastructure, CI/CD, testing, and production support Ability to take ownership and make sound technical decisions Strong communication skills and a practical approach to solving problems Nice to have Experience in any of the following would be useful, but is not required : Azure or another major cloud platform Payments Mobile application backends Access-control, IoT, or hardware-connected systems CRM, ERP, CMS, or operational platforms Umbraco Microservices or event-driven systems Leading or mentoring other developers Why join? This isn’t a maintenance role. You’ll have the opportunity to influence the architecture of a major new platform, replace legacy technology with modern systems, and see the software you build used directly by customers and operations. You’ll join at an important stage of the project with the opportunity to take real technical ownership and grow into a broader leadership role as the engineering team expands. Offer: $5,000 — $6,000 (depending on experience) Rewarding bonuses for milestones hit. Work in a new high-tech office in Warsaw Long-term growth opportunities and career progression Relocation support to Warsaw (If needed)