Backend Developer (Node.JS)

🏢 Summary: Oferta dla Mid+/Senior Backend Developera do budowy nowej, rozbudowanej aplikacji od podstaw. Projekt w PHP potrwa 4–6 miesięcy i wymaga doświadczenia z frameworkami Symfony lub Laravel oraz projektowaniem skalowalnych, wydajnych systemów backendowych. 🗂️ Requirements: Bardzo dobra znajomość PHP, Doświadczenie z Symfony i/lub Laravel, Doświadczenie w projektowaniu i budowaniu rozbudowanych aplikacji, Znajomość usług AWS, Rozumienie architektury backendowej, skalowalności i wydajności, Samodzielność w podejmowaniu decyzji technicznych i rozwiązywaniu problemów 📃 Skills: PHP, Symfony, Laravel, AWS 🏢 Description: Szukamy Backend Developera na poziomie Mid+ / Senior , który dołączy do zespołu tworzącego nową aplikację od podstaw. Szukamy osoby, która dobrze czuje się w PHP, ma doświadczenie w budowaniu rozbudowanych systemów. Projekt przewidziany na 4-6 m-cy. Wymagania Bardzo dobra znajomość PHP Doświadczenie z Symfony i/lub Laravel Doświadczenie w projektowaniu i budowaniu rozbudowanych aplikacji Znajomość usług AWS Dobre rozumienie architektury backendowej, skalowalności i wydajności Samodzielność w podejmowaniu decyzji technicznych i rozwiązywaniu problemów Mile widziane Doświadczenie z narzędziami AI wspierającymi programowanie, np. Cursor, GitHub Copilot itp. Znajomość Node.js Znajomość Pythona Znajomość JavaScript

🏢 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: Long-term remote B2B contract for an experienced Backend Developer to build and support cloud-based solutions using .NET and AWS. The role requires end-to-end ownership, from requirements and implementation through deployment and support, in an Agile international environment. 🗂️ Requirements: Strong C# and .NET Core experience, Entity Framework experience, AWS and cloud architecture experience, GitLab and CI/CD experience, SOLID and clean code knowledge, Agile or Kanban experience, End-to-end delivery ownership, Effective technical and non-technical communication 📃 Skills: C#, .NET, AWS, EntityFramework, GitLab, CI/CD, SOLID, Agile, Kanban 🏢 Description: Experienced Backend Developer (.NET / AWS) What we are looking for We are looking for an experienced Backend Developer with AWS experience who enjoys taking ownership and driving work from idea to production. You are comfortable working in a complex environment, eager to understand the business and domain, and motivated by improving both the product and the way we work. You enjoy collaborating with business stakeholders, fellow developers and architects, communicate effectively with both technical and non-technical audiences, and thrive in an international environment. What we offer: Long Term B2B Contract Rate: 40-45 euro/h + VAT Remote role Core Technical Requirements • Strong experience with C# and .NET core (we use .NET 10) • Entity Framework • Solid AWS knowledge and experience with cloud-based architectures • Experience with GitLab and CI/CD practices • Understanding of SOLID principles and clean code practices • Experience working in Agile/Kanban environments • Ability to independently drive work from requirements through implementation, deployment and support

🏢 Summary: Long-term remote B2B contract for an experienced Backend Developer to own the delivery of cloud-based .NET solutions from requirements through production support. The role offers €40–45/hour plus VAT and requires collaboration with business stakeholders, developers, and architects in an international environment. 🗂️ Requirements: Strong C# and .NET Core experience, Entity Framework experience, AWS and cloud-architecture experience, GitLab and CI/CD experience, SOLID principles and clean-code practices, Agile or Kanban experience, Independent delivery from requirements through deployment and support, Effective communication with technical and non-technical stakeholders 📃 Skills: C#, .NET, AWS, EntityFramework, GitLab, CI/CD, SOLID, Agile, Kanban 🏢 Description: Experienced Backend Developer (.NET / AWS) What we are looking for We are looking for an experienced Backend Developer with AWS experience who enjoys taking ownership and driving work from idea to production. You are comfortable working in a complex environment, eager to understand the business and domain, and motivated by improving both the product and the way we work. You enjoy collaborating with business stakeholders, fellow developers and architects, communicate effectively with both technical and non-technical audiences, and thrive in an international environment. What we offer: Long Term B2B Contract Rate: 40-45 euro/h + VAT Remote role Core Technical Requirements • Strong experience with C# and .NET core (we use .NET 10) • Entity Framework • Solid AWS knowledge and experience with cloud-based architectures • Experience with GitLab and CI/CD practices • Understanding of SOLID principles and clean code practices • Experience working in Agile/Kanban environments • Ability to independently drive work from requirements through implementation, deployment and support

🏢 Summary: Remote B2B frontend engineering role building a platform for European venture capital firms. The position centers on developing scalable React and Next.js applications, with optional backend contributions in C# and .NET. 🗂️ Requirements: 5+ years of professional software development experience, Commercial experience with React and Next.js, Very good JavaScript and TypeScript knowledge, Experience building responsive, maintainable web applications, Experience integrating frontend applications with REST APIs, Understanding of frontend architecture, performance, and development best practices, Excellent English skills 📃 Skills: React, Next.js, JavaScript, TypeScript, REST, APIs 🏢 Description: Does building awesome, innovative products that add up to something meaningful sound like a dream come true? Come join us and make that vision a reality! About You will be fully integrated into our client’s remote engineering team , working on a cutting-edge platform tailored specifically for venture capital firms across Europe . The role is primarily focused on frontend development , with the opportunity to contribute to backend development in .NET depending on your experience and interests. Responsibilities Design, develop, and maintain modern, scalable frontend applications using React and Next.js Build reusable, high-quality UI components and deliver intuitive user experiences Translate business and product requirements into reliable technical solutions Collaborate closely with backend developers, product stakeholders, and other members of the engineering team Integrate frontend applications with APIs and backend services Contribute to application architecture, code quality, performance, and maintainability Participate in code reviews and technical discussions Optionally contribute to backend development using C# and .NET Our offer Competitive salary on a B2B contract Fully remote position Real impact and independence at work Individual career path Work-life balance A non-corporate atmosphere where innovation, personal growth, and teamwork thrive Collaboration with 100+ smart, curious & ambitious engineers What you bring 5+ years of professional software development experience Strong commercial experience with React and Next.js Very good knowledge of JavaScript / TypeScript Experience building modern, responsive, and maintainable web applications Experience integrating frontend applications with REST APIs Good understanding of frontend architecture, performance, and software development best practices Excellent English language skills Nice to have: Experience with C# and .NET / .NET Core Experience with MS SQL Understanding of microservices architecture Experience working on B2C or complex web applications Interest in financial markets or venture capital

🏢 Summary: Senior Back-end Developer role focused on designing secure, reliable Node.js/TypeScript backends for real-time automated decision-making. The position involves microservices, databases, APIs, cloud deployments, automated testing, production support, and AI-assisted development in an agile international team. 🗂️ Requirements: 5+ years of Node.js, JavaScript, and TypeScript experience, Relational database experience, Microservices and system design knowledge, Test pyramid implementation experience, Security best practices, AI-assisted development tool proficiency, English proficiency, Afternoon/evening availability for cross-time-zone collaboration 📃 Skills: Node.js, JavaScript, TypeScript, PostgreSQL, MySQL, Docker, Kubernetes, AWS, Fargate, Lambda, Nest.js, Cursor, Devin 🏢 Description: Senior Back-end Developer (Node.js / TypeScript) About the Role We are looking for a Senior Back-end Developer to join our client's team. You will architect and implement robust backends, interacting with various data stores and third-party APIs to support real-time automated decision-making. Working in an agile, multinational environment, you'll have huge creative freedom and ownership over your projects while collaborating closely with Product Managers, Senior Engineers, and Architects. Key Responsibilities Architect and implement backends and their interactions with data stores and APIs. Support reliable databases and APIs for real-time automated decision-making. Deploy software using industry-standard tooling like Kubernetes clusters and AWS Lambda functions. Investigate and resolve production issues, implementing timely fixes to minimize user impact. Focus heavily on security, following Defense in Depth principles and ensuring containers are secure. Implement robust automated test suites (unit, integration, and e2e) to maintain a low failure rate. Leverage AI-assisted development tools (such as Cursor, Claude Code, or Devin) as a core part of your daily workflow to accelerate speed and quality. Requirements 5+ years of hands-on experience with Node.js, JavaScript, and TypeScript . Practical knowledge of at least one relational database system (e.g., PostgreSQL, MySQL, or SQL Server). Adept with microservices and system design patterns. Experience implementing the test pyramid and utilizing good security practices. Strong sense of ownership, independence, and the ability to clearly convey ideas across technical and non-technical teams. Comfort with AI-assisted development tools as a core part of your setup. Good command of English (written and spoken). Availability in the afternoons/evenings for occasional alignment with multinational teams across time zones. Tech Stack & Tools Backend: Node.js, TypeScript, Nest.js Cloud & DevOps: Docker, Kubernetes, AWS (Fargate, Lambda) Testing: Automated software testing (unit, integration, e2e) AI Tools: Cursor, Claude Code, Devin (autonomous AI engineer) Nice-to-Haves Familiarity with Docker/Kubernetes/AWS deployment processes. Experience with profiling and performance optimization. Experience giving high-quality feedback during code reviews.

🏢 Summary: Develop and enhance secure, intuitive React-based web applications that help prevent payment fraud. The role works in a multidisciplinary Scrum team, integrating frontend solutions with backend services and cloud infrastructure. 🗂️ Requirements: 4+ years of professional React application development experience, JavaScript, TypeScript, HTML5 and CSS3 expertise, RESTful API integration experience, Microfrontend experience, Frontend performance optimisation and responsive design experience, Agile Scrum experience, Git, Webpack, CI/CD pipeline and Jenkins experience, Basic NestJS knowledge, AWS knowledge: CloudWatch, S3, DynamoDB and ECS 📃 Skills: React, JavaScript, TypeScript, HTML5, CSS3, SASS, REST, Microfrontends, Git, Webpack, CI/CD, Jenkins, NestJS, AWS, CloudWatch, S3, DynamoDB, ECS 🏢 Description: Summary: The Frontend Developer role focuses on enhancing user experience through the development of innovative, secure, and intuitive web solutions aimed at preventing payment fraud. Must Haves 4+ years of professional experience developing applications with React and NestJs. Strong experience with JavaScript, TypeScript, HTML5, and CSS3 (SASS, styled-components, or similar). Experience integrating with RESTful APIs and working with micro frontends. Experience with frontend performance optimisation and responsive design. Good understanding of Agile methodologies (Scrum). Experience using Git, Webpack, CI/CD pipelines, and Jenkins. Familiarity with AWS services, particularly: CloudWatch, S3, DynamoDB, ECS (Elastic Container Service). Nice to Haves Knowledge of component libraries such as Material UI or Chakra UI. Experience with frontend testing frameworks such as Jest, React Testing Library, or Cypress. Understanding of cloud-native architectures and modern deployment practices. A proactive, solution-oriented mindset with a strong sense of ownership. Excellent communication skills and the ability to work effectively in cross-functional teams. Other Details Team Structure: Multi-disciplinary Scrum team consisting of Frontend Developers, Backend Developers, DevOps Engineers, QA Engineers, UX/UI Designers, and Product Owners.