Senior Full-Stack Developer (with Optimizely)

🏢 Summary: Offer for a Senior Frontend Developer specializing in Angular to design, build, and maintain scalable, high-quality web applications within diverse software projects. The role involves frontend architecture decisions, integration with backend services, and collaboration in Agile teams. Contract is B2B with remote flexibility and focus on delivering production-grade solutions. 🗂️ Requirements: 5+ years Frontend development experience, Strong Angular 2+ expertise, Proficiency in JavaScript and TypeScript, Knowledge of HTML5 and CSS3, Experience with NgRx or state management, Experience integrating REST APIs, Familiarity with Webpack, Vite, npm or yarn, Experience with testing frameworks, Knowledge of CI/CD pipelines, Proficiency with Git, Experience in Agile/Scrum, English B2 or higher, Experience with AI tools or AI-powered features 📃 Skills: Angular, JavaScript, TypeScript, HTML5, CSS3, NgRx, REST, Webpack, Vite, npm, yarn, Jasmine, Karma, Cypress, Git, CICD, Agile, Scrum, AI 🏢 Description: Who we are: We are Inspeerity (part of DevelopX group), engineering consultancy providing software development and consultancy. Our primary expertise is systems architecture and full stack development – from defining project requirements, to designing, building, and deploying software applications for web, backend, enterprise and mobile. We are crazy about technology, serious about people. About position: We are currently building our talent pool for future Senior Frontend Developer (Angular) roles. As our company is expanding, you may have the opportunity to work on a variety of software solutions across multiple initiatives, including projects we will be delivering in the future, from building native AI solutions to modernizing legacy systems. If you enjoy collaborating in a skilled team and are committed to delivering top-notch software, we’d love to connect. We're not prescriptive about background. Whether you've worked in fintech, SaaS, e-commerce, or enterprise systems - what matters is that you've shipped production software at scale, cared about its reliability, and learned from what broke. TL;DR • Who: Senior Frontend Developer (Angular) • Contract Type: B2B Framework Agreement • Salary range: Up to 140 PLN/h • Company: Software House What you’ll be doing: • Designing, implementing, and maintaining high-quality frontend applications using Angular. • Building responsive, user-friendly interfaces and reusable UI components. • Collaborating with cross-functional teams including backend developers, designers, and product stakeholders. • Reviewing and refactoring code to ensure maintainability, performance, and scalability. • Participating in technical design discussions and contributing to frontend architecture decisions. • Writing and maintaining technical documentation for components and frontend processes. • Supporting integration with backend services and APIs. You will be the best fit if you have: • 5+ years of experience as a Frontend Developer, with strong expertise in Angular (2+). • Strong understanding of JavaScript / TypeScript, HTML5, and CSS3. • Experience with state management solutions (e.g., NgRx) and component-based architecture. • Experience with RESTful APIs and integration with backend services. • Familiarity with modern frontend tooling (e.g., Webpack, Vite, npm/yarn). • Knowledge of performance optimization techniques and building scalable web applications. • Experience with testing frameworks (e.g., Jasmine, Karma, Cypress or similar). • Knowledge of CI/CD pipelines and version control systems (e.g., Git). • Strong problem-solving skills and attention to detail. • English level B2 or higher. • Experience working in Agile/Scrum teams and contributing to iterative development. • Experience with AI technologies, including using AI tools for development and building AI-powered features or applications. What we offer • Remote work or working from our Bialystok, Warsaw, Rzeszow offices. It's up to you! • Collaboration with experienced and engaged people who will appreciate your work and support you whenever you need it 😊 • Hybrid and flexible cooperation model based on a B2B Framework Agreement. • Great working conditions and best equipment: Dell or MacBook, your choice. Good to know: We don’t require a degree. We don’t do whiteboard puzzles or trick questions. Our interview process is practical: a technical conversation, and a chat about how you work. We value direct communication and intellectual curiosity. If you’re someone who gets excited debugging a tricky concurrency issue - not because you have to, but because you want to understand it — we’ll get along well.

🏢 Summary: Senior Frontend Developer (React) role focused on designing and delivering scalable, high-quality frontend applications using React and Next.js across diverse software projects, including AI-driven and legacy modernization initiatives. The position involves architectural decisions, performance optimization, API integration, and collaboration within cross-functional Agile teams. B2B contract with opportunity to work on production systems at scale. 🗂️ Requirements: 5+ years experience as Frontend Developer, Strong expertise in React, Proficiency in JavaScript, Proficiency in TypeScript, Strong knowledge of HTML5, Strong knowledge of CSS3, Experience with Next.js including SSR and SSG, Experience with state management libraries, Experience integrating RESTful APIs, Familiarity with modern frontend tooling, Experience with testing frameworks, Knowledge of CI/CD pipelines, Proficiency with Git, Experience working in Agile/Scrum, English level B2 or higher 📃 Skills: React, Next.js, JavaScript, TypeScript, HTML5, CSS3, Redux, Zustand, REST, Vite, Webpack, npm, yarn, Jest, ReactTestingLibrary, Cypress, CI/CD, Git, Agile, Scrum, AI 🏢 Description: Who we are: We are Inspeerity (part of DevelopX group), engineering consultancy providing software development and consultancy. Our primary expertise is systems architecture and full stack development – from defining project requirements, to designing, building, and deploying software applications for web, backend, enterprise and mobile. We are crazy about technology, serious about people. About position: We are currently building our talent pool for future Senior Frontend Developer (React) roles. As our company is expanding, you may have the opportunity to work on a variety of software solutions across multiple initiatives, including projects we will be delivering in the future, from building native AI solutions to modernizing legacy systems. If you enjoy collaborating in a skilled team and are committed to delivering top-notch software, we’d love to connect. e're not prescriptive about background. Whether you've worked in fintech, SaaS, e-commerce, or enterprise systems — what matters is that you've shipped production software at scale, cared about its reliability, and learned from what broke. TL;DR • Who: Senior Frontend Developer (React) • Contract Type: B2B Framework Agreement • Salary range: Up to 140 PLN/h • Company: Software House What you’ll be doing: • Designing, implementing, and maintaining high-quality frontend applications using React. • Building modern, responsive user interfaces and reusable components. • Working with frameworks like Next.js to deliver performant, scalable applications (including SSR/SSG when applicable). • Collaborating with cross-functional teams including backend developers, designers, and product stakeholders. • Reviewing and refactoring code to ensure maintainability, performance, and scalability. • Participating in technical design discussions and contributing to frontend architecture decisions. • Writing and maintaining technical documentation for components and frontend processes. • Supporting integration with backend services and APIs. You will be the best fit if you have: • 5+ years of experience as a Frontend Developer, with strong expertise in React. • Strong understanding of JavaScript / TypeScript, HTML5, and CSS3. • Experience building applications with frameworks such as Next.js, including server-side rendering and static generation. • Experience with state management approaches (e.g., Redux, Zustand, or similar). • Experience with RESTful APIs and integration with backend services. • Familiarity with modern frontend tooling (e.g., Vite, Webpack, npm/yarn). • Knowledge of performance optimization techniques and building scalable web applications. • Experience with testing frameworks (e.g., Jest, React Testing Library, Cypress or similar). • Knowledge of CI/CD pipelines and version control systems (e.g., Git). • Strong problem-solving skills and attention to detail. • English level B2 or higher. • Experience working in Agile/Scrum teams and contributing to iterative development. • Experience with AI technologies, including using AI tools for development and building AI-powered features or applications. What we offer • Remote work or working from our Bialystok, Warsaw, Rzeszow offices. It's up to you! • Collaboration with experienced and engaged people who will appreciate your work and support you whenever you need it 😊 • Hybrid and flexible cooperation model based on a B2B Framework Agreement. • Great working conditions and best equipment: Dell or MacBook, your choice. Good to know: We don’t require a degree. We don’t do whiteboard puzzles or trick questions. Our interview process is practical: a technical conversation, and a chat about how you work. We value direct communication and intellectual curiosity. If you’re someone who gets excited debugging a tricky concurrency issue - not because you have to, but because you want to understand it — we’ll get along well.

🏢 Summary: Senior .NET Developer role focused on designing, building, and maintaining scalable .NET applications and APIs across diverse projects, including AI-driven and legacy modernization initiatives. The position involves backend development, architectural input, code quality improvement, and cloud-based deployments within Agile teams. B2B contract with flexible remote collaboration. 🗂️ Requirements: 5+ years experience with C# and .NET, .NET Core / .NET 6+ experience, ASP.NET Core experience, Entity Framework experience, Experience building RESTful APIs, SQL and NoSQL database experience, Cloud platform experience (AWS, Azure, or GCP), CI/CD pipeline knowledge, Git version control proficiency, Understanding of OOP and design patterns, Experience in Agile/Scrum, English level B2+ 📃 Skills: C#, .NET, .NETCore, ASP.NET, EntityFramework, REST, SQL, PostgreSQL, MySQL, MongoDB, AWS, Azure, GCP, CI/CD, Git, OOP, Scrum, AI 🏢 Description: Who we are: We are Inspeerity (part of DevelopX group), engineering consultancy providing software development and consultancy. Our primary expertise is systems architecture and full stack development – from defining project requirements, to designing, building, and deploying software applications for web, backend, enterprise and mobile. We are crazy about technology, serious about people. About position: We are currently building our talent pool for future Senior .NET Developer roles. As our company is expanding, you may have the opportunity to work on a variety of software solutions across multiple initiatives, including projects we will be delivering in the future, from building native AI solutions to modernizing legacy systems. If you enjoy collaborating in a skilled team and are committed to delivering top-notch software, we’d love to connect. We're not prescriptive about background. Whether you've worked in fintech, SaaS, e-commerce, or enterprise systems, what matters is that you've shipped production software at scale, cared about its reliability, and learned from what broke. TL;DR • Who: Senior .NET Developer • Contract Type: B2B Framework Agreement • Salary range: Up to 150 PLN/h • Company: Software House What you’ll be doing: • Designing, implementing, and maintaining high-quality .NET applications. • Developing backend components and APIs to support scalable software solutions. • Collaborating with cross-functional teams. • Reviewing and refactoring code to ensure maintainability, performance, and security. • Participating in technical design discussions and contributing to architecture decisions. • Writing and maintaining technical documentation for systems, APIs, and processes. • Supporting deployment and integration of applications in different environments. You will be the best fit if you have: • 5+ years of experience as a C#/.NET developer, preferably with exposure to .NET Core / .NET 6+ , ASP.NET Core , Entity Framework or similar frameworks. • Strong understanding of object-oriented programming, design patterns, and clean code principles. • Experience with RESTful APIs and web services integration. • Familiarity with SQL and NoSQL databases (e.g., PostgreSQL, MySQL, MongoDB). • Experience with cloud environments such as AWS, Azure, or GCP. • Knowledge of CI/CD pipelines and version control systems (e.g., Git). • Strong problem-solving skills and ability to troubleshoot complex issues. • English level B2 or higher. • Experience working in Agile/Scrum teams and contributing to iterative development. • Experience with AI technologies, including using AI tools for development and building AI-powered features or applications. What we offer • Remote work or working from our Bialystok, Warsaw, Rzeszow offices. It's up to you! • Collaboration with experienced and engaged people who will appreciate your work and support you whenever you need it 😊 • Hybrid and flexible cooperation model based on a B2B Framework Agreement. • Great working conditions and best equipment: Dell or MacBook, your choice. Good to know: We don’t require a degree. We don’t do whiteboard puzzles or trick questions. Our interview process is practical: a technical conversation, and a chat about how you work. We value direct communication and intellectual curiosity. If you’re someone who gets excited debugging a tricky concurrency issue - not because you have to, but because you want to understand it — we’ll get along well.

🏢 Summary: Full Stack Development Lead role focused on delivering end-to-end solutions using React and C# .NET Core in a cloud-driven, microservices-based environment. The position combines hands-on development with architectural input and technical leadership in a fully remote B2B setup. The role involves close collaboration with cross-functional teams and contribution to modern DevOps and data workflows. 🗂️ Requirements: Proven full-stack experience with React, TypeScript, C# .NET Core, Strong knowledge of microservices architecture, Understanding of distributed systems, Experience with CI/CD pipelines, Experience with cloud platforms (Azure preferred), Experience with containers, Familiarity with DevOps practices, Ability to design APIs and event-driven components 📃 Skills: React, TypeScript, C#, .NET, Microservices, CI/CD, Azure, Docker, DevOps, PySpark, PowerBI, APIs 🏢 Description: Start Date: ASAP / Within 1 Month / Flexible Work Model: 100% remote Contract Type: B2B (160-180 PLN/h + VAT) We are looking for an experienced Full Stack Development Lead who will take ownership of end‑to‑end solutions across React and C# .NET Core while contributing to technical direction and supporting a collaborative engineering culture. This role is ideal for a strong Senior Full Stack Developer who is ready to expand into leadership responsibilities, work closely with cross‑functional teams, and influence architectural decisions in a modern, cloud‑driven environment. Expectations Proven experience in full‑stack development using React, TypeScript, and C# .NET Core. Good understanding of microservices , distributed systems, and CI/CD pipelines. Exposure to cloud platforms (Azure preferred), containers, and modern DevOps practices. Experience with data workflows (pyspark) or BI solutions (Power BI) is a strong advantage. Ability to collaborate with technical and business stakeholders and take initiative in solution design. Responsibilities Contribute to the design and delivery of full‑stack applications using React and C# .NET Core. Support architectural discussions around microservices, APIs, and event‑driven components. Collaborate with data engineers on pyspark workflows and Power BI reporting enhancements. Promote engineering best practices, code quality, and maintainable development patterns. Mentor team members and support planning, collaboration, and continuous improvement efforts. What We Offer Medicover healthcare package Multisport card Access to an e-learning platform Group life insurance

🏢 Summary: B2B contract opportunity for a Senior Node.js Developer to design, build, and maintain scalable backend applications and APIs across diverse software projects, including AI-driven and legacy modernization initiatives. The role focuses on high-quality Node.js development, architecture contribution, and cloud-based deployments in Agile teams. 🗂️ Requirements: 5+ years of experience in Node.js development, Experience with Express.js or NestJS frameworks, Strong knowledge of JavaScript and TypeScript, Understanding of asynchronous programming and event-driven architecture, Experience building and integrating RESTful APIs, Experience with SQL and NoSQL databases, Experience with cloud platforms (AWS, Azure, or GCP), Knowledge of CI/CD pipelines, Experience with version control systems, Experience working in Agile/Scrum teams, English level B2 or higher, Experience with AI technologies and AI-powered features development 📃 Skills: Node.js, Express.js, NestJS, JavaScript, TypeScript, REST, SQL, NoSQL, PostgreSQL, MySQL, MongoDB, AWS, Azure, GCP, CI/CD, Git, AI 🏢 Description: Who we are: We are Inspeerity (part of DevelopX group), engineering consultancy providing software development and consultancy. Our primary expertise is systems architecture and full stack development – from defining project requirements, to designing, building, and deploying software applications for web, backend, enterprise and mobile. We are crazy about technology, serious about people. About position: We are currently building our talent pool for future Senior Node.js Developer roles. As our company is expanding, you may have the opportunity to work on a variety of software solutions across multiple initiatives, including projects we will be delivering in the future, from building native AI solutions to modernizing legacy systems. If you enjoy collaborating in a skilled team and are committed to delivering top-notch software, we’d love to connect. We're not prescriptive about background. Whether you've worked in fintech, SaaS, e-commerce, or enterprise systems — what matters is that you've shipped production software at scale, cared about its reliability, and learned from what broke. TL;DR • Who: Senior Node.js Developer • Contract Type: B2B Framework Agreement • Salary range: Up to 150 PLN/h • Company: Software House What you’ll be doing: • Designing, implementing, and maintaining high-quality Node.js applications. • Developing backend components and APIs to support scalable software solutions. • Collaborating with cross-functional teams. • Reviewing and refactoring code to ensure maintainability, performance, and security. • Participating in technical design discussions and contributing to architecture decisions. • Writing and maintaining technical documentation for systems, APIs, and processes. • Supporting deployment and integration of applications in different environments. You will be the best fit if you have: • 5+ years of experience as a Node.js developer, preferably with exposure to frameworks such as Express.js , NestJS , or similar. • Strong understanding of JavaScript/TypeScript, asynchronous programming, and event-driven architecture. • Experience with RESTful APIs and web services integration. • Familiarity with SQL and NoSQL databases (e.g., PostgreSQL, MySQL, MongoDB). • Experience with cloud environments such as AWS, Azure, or GCP. • Knowledge of CI/CD pipelines and version control systems. • Strong problem-solving skills and ability to troubleshoot complex issues. • Experience working in Agile/Scrum teams and contributing to iterative development. • English level B2 or higher. • Experience with AI technologies, including using AI tools for development and building AI-powered features or applications. What we offer • Remote work or working from our Bialystok, Warsaw, Rzeszow offices. It's up to you! • Collaboration with experienced and engaged people who will appreciate your work and support you whenever you need it 😊 • Hybrid and flexible cooperation model based on a B2B Framework Agreement. • Great working conditions and best equipment: Dell or MacBook, your choice. Good to know: We don’t require a degree. We don’t do whiteboard puzzles or trick questions. Our interview process is practical: a technical conversation, and a chat about how you work. We value direct communication and intellectual curiosity. If you’re someone who gets excited debugging a tricky concurrency issue - not because you have to, but because you want to understand it — we’ll get along well.

🏢 Summary: B2B contract for a Senior React Native Developer to build and maintain a white-label, multi-tenant mobile ordering platform for iOS and Android. The role focuses on developing scalable, production-grade applications with advanced mobile features and clean architecture. Initial 4-month engagement with possible extension, starting in June. 🗂️ Requirements: Minimum 3 years commercial experience with React Native and shipped production apps, Strong TypeScript skills including strict mode, generics, utility types, Deep knowledge of React Navigation and complex navigation patterns, Experience with React Native Reanimated (v2+) and gesture-based interactions, Solid knowledge of iOS and Android build systems (Gradle, Xcode, signing, schemes/flavours), Experience debugging native crashes and JS bundle issues, Proficiency with TanStack Query (or React Query), Experience with Zustand or similar state management, Ability to design and maintain typed API clients and data-fetching layer, Experience with modular or feature-based architecture, English level B2 or higher, Experience working in Agile/Scrum environments 📃 Skills: ReactNative, TypeScript, ReactNavigation, Reanimated, Zustand, TanStackQuery, iOS, Android, Gradle, Xcode, JavaScript, Scrum 🏢 Description: We are looking for an experienced Senior React Developer to join the team working on a white-label mobile ordering platform for restaurants. The product is built as a shared, multi-tenant solution, where each client receives their own fully branded mobile application powered by a common codebase. Who we are: We are Inspeerity (part of DevelopX group), engineering consultancy providing software development and consultancy. Our primary expertise is systems architecture and full stack development – from defining project requirements, to designing, building, and deploying software applications for web, backend, enterprise and mobile. We are crazy about technology, serious about people. TL;DR • Who : Senior React Native Developer • Contract Type : B2B • Salary range: Up to 150 PLN/h + VAT • Start date : from ~9th June • Term of the agreement : ~ 4 months with possibility of prolongation What you’ll be doing: Developing and maintaining production-grade mobile applications in React Native for iOS and Android platforms. Designing and implementing scalable, maintainable, and modular application architecture within a multi-tenant / white-label environment. Building advanced mobile features using TypeScript, React Navigation, Reanimated, and gesture-based interactions. Managing application state, server communication, caching, and API integrations using TanStack Query, Zustand, and typed API clients. Ensuring high code quality through clean architecture, reusable components, strong naming conventions, and maintainable code practices. Participating in agile development processes, including sprint planning, reviews, demos, and close collaboration with international stakeholders. Presenting delivered features during sprint reviews and proactively suggesting product and technical improvements. Supporting the QA process during regression testing and contributing to overall product stability and performance. You will be the best fit if you have: At least 3 years of commercial React Native experience with shipped production apps. Strong TypeScript skills - strict mode, generics, utility types. Deep understanding of React Navigation and complex navigation patterns. Experience with React Native Reanimated (v2+) and gesture-based interactions. Solid knowledge of iOS and Android build systems (schemes/flavours, signing, Gradle, Xcode). Experience debugging native crashes, JS bundle issues. Proficiency with TanStack Query (or React Query). Experience with Zustand or comparable lightweight state management. Ability to design and maintain a clean data-fetching layer with typed API clients. Experience working in a feature-based or modular architecture. Comfortable presenting your own work to stakeholders every two weeks. Proactive mindset: expected to raise observations, propose improvements, and drive initiatives - not just execute tickets. Strong problem-solving and debugging skills. English level B2 or higher. Hands-on experience working in Agile / Scrum environments. What we offer: Hybrid and flexible cooperation model based on a B2B contract. Remote work or working from our Bialystok, Warsaw, Rzeszow offices. It's up to you! Great working conditions and best equipment. Collaboration with experienced and engaged people who will appreciate your work and support you whenever you need it.

🏢 Summary: Senior Fullstack Developer role in an international product development team focused on building and maintaining secure, scalable fullstack applications using Java and modern frontend technologies. The position involves hands-on backend and frontend development, microservices architecture, SPA development, and collaboration within Agile teams in an English-speaking environment. Hybrid work model in Warsaw with long-term B2B engagement. 🗂️ Requirements: 10+ years of software development experience, Strong fullstack development experience, Expert knowledge of Java, Experience with Spring, Experience building microservices, Experience with Single Page Applications, Knowledge of frontend technologies, Experience designing secure and scalable applications, Understanding of testing and code quality practices, Experience working in Agile environments, Strong analytical and problem-solving skills, Very good English skills, EU citizenship, Residence in Poland 📃 Skills: Java, Spring, SpringBoot, Microservices, SPA, Agile, CI/CD, DevOps, Docker, Kubernetes, Cloud 🏢 Description: In Cyclad we work with top international IT companies in order to boost their potential in delivering outstanding, cutting-edge technologies that shape the world of the future. We are currently looking for an experienced Senior Fullstack Developer to join an international team responsible for developing and maintaining modern, secure, and scalable applications supporting critical business processes. You will work in a hands-on development role across both backend and frontend technologies, contributing to high-quality software delivery while collaborating with international stakeholders in an English-speaking environment. Project information: Type of project: Product Development Office location: Warsaw, Poland Work mode: Hybrid (3 days from the office, 2 days remotely) Budget: 100- 130 PLN net/ h- B2B Project length: Long-term Only candidates with citizenship in the European Union and residence in Poland Start date: ASAP (depending on candidate’s availability) Project scope: Design, develop, and maintain modern fullstack applications Build secure, scalable, maintainable, and testable software aligned with business requirements Develop and evolve Java-based microservices using Spring Boot Design and implement modern Single Page Applications (SPA) following frontend best practices Collaborate closely with business and technical stakeholders to translate requirements into high-quality technical solutions Ensure application reliability, performance, and service continuity Follow software engineering best practices, including code quality, testing, and security standards Participate in code reviews and contribute to continuous improvement initiatives Work within Agile development teams in an international English-speaking environment Support the evolution of existing applications while contributing to the development of new features and services Competence demands: 10+ years of professional experience in software development Strong experience as a full-stack developer with expertise in backend and frontend development Excellent knowledge of Java and Spring Boot Proven experience developing microservices-based applications Strong experience with modern frontend technologies and Single Page Applications (SPA) Experience designing secure, scalable, and high-performance applications Solid understanding of software engineering best practices, including testing, code quality, and clean architecture Experience working in Agile development environments Strong analytical and problem-solving skills Excellent communication skills and ability to collaborate with business and technical stakeholders Very good English skills Nice to have: Experience with cloud platforms Knowledge of CI/CD pipelines and DevOps practices Experience with containerization technologies such as Docker and Kubernetes Experience working in international enterprise environments We offer: Hybrid working model Full-time job agreement based on b2b Private medical care with dental care (covering 70% of costs) Multisport card (also for an accompanying person) Life inssurance Recruitment process: Introductory call Technical interview Final decision

🏢 Summary: Senior Full-Stack Engineer role with a 50/50 backend and frontend focus, building scalable microservices-based applications using ASP.NET (C#) and React with TypeScript in a cloud-native environment. The position involves designing and maintaining REST APIs, developing responsive user interfaces, ensuring high test coverage, and contributing to architectural decisions with strong technical ownership. Poland-based employment (Umowa o Pracę) with remote flexibility and quarterly in-person collaboration. 🗂️ Requirements: MSc+ in Computer Science or equivalent, Minimum 5 years experience with ASP.NET and C#, Minimum 5 years experience building REST APIs, Minimum 5 years experience with React, Experience with TypeScript, Strong knowledge of microservices architecture, Knowledge of cloud design patterns, Experience with unit, integration, and end-to-end testing, High level of technical ownership, Fluent English (minimum B2), Poland residency 📃 Skills: ASP.NET, C#, REST, React, TypeScript, Microservices, AWS, Agile, DDD, UnitTesting, IntegrationTesting, E2ETesting, Cloud 🏢 Description: We’re looking for a Senior Full-Stack Engineer who brings deep technical expertise and a collaborative mindset to our product development team. You will work with a modern microservices architecture, building scalable backend services using the ASP.NET Web API with C#, and intuitive frontend interfaces using mainly React and TypeScript. This is a hands-on engineering role with a 50/50 front-/backend focus, ideal for someone who likes to take ownership, thrives in a dynamic product team, and enjoys mentoring others. This role could easily become a Tech Lead role in a foreseeable future. If you're passionate about designing high-impact software in a cloud-native environment, we’d love to hear from you. This Poland-based role offers remote flexibility, but we value in-person collaboration. Our team meets in Poland for at least one week each quarter, so we request all applicants to be located in Poland. This is not a globally remote role. Poland residency is required. The contract form is Umowa o Pracę (only, no B2B). What you will be responsible for Collaborate proactively in refinement sessions with product and tech teams to ensure clarity and feasibility of features. Design, implement, and maintain scalable web APIs using ASP.NET and microservices architecture principles. Develop responsive user interfaces with React and TypeScript that enhance usability and performance. Work closely with Product Owners to clarify feature requirements and ensure business context is well-understood. Define, design and align feature architecture with the Head of Engineering to ensure consistency and scalability. Ensure features meet Definition of Done, with state-of-the-art unit, integration, and end-to-end test coverage. Support incident response and production issue resolution as per team standards. Actively contribute to team knowledge sharing and coach colleagues in technical best practices. What makes you a match Essential Qualifications: MSc+ in Computer Science or equivalent 5 years of proven experience in building secure REST APIs using ASP.NET , as well as developing solid front-end applications with React are non-negotiable must haves. Comprehensive knowledge of contemporary web application architectures, with a focus on microservices and cloud design patterns. Demonstrated ability of high technical Ownership and Tech Leadership are a requirement for this role. Bonus Skills: Hands-on experience with AWS infrastructure. Experience working in cross-functional product teams using Agile practices and following Domain-Driven Design (DDD). Collaboration and Interpersonal Skills: Clear and adaptive communication with both technical and non-technical stakeholders. Strong sense of ownership, accountability, and proactive problem-solving. Languages: English: B2 - (No certificate required, but Fluency) German, Polish, Ukrainian: desired, not required What you can expect A dynamic, ambitious team where your voice is heard, and your contributions truly matter. You’ll have real ownership over your decisions in a trusted, cross-functional environment within a Swiss product company that puts people first. We offer fair compensation, flexible working hours, a hybrid work setup, and a culture that supports both personal and professional growth, fostering a healthy work-life balance. Employer of Record: For this role, we offer employment through our trusted Employer of Record provider Remote.com , ensuring full legal compliance and a seamless experience for our team members in Poland. ID Verification: To maintain a fair and secure hiring process, candidates may be asked to verify their identity their identity before speaking with our Recruiter. This step helps us prevent fraud and focus our resources on genuine applicants. About us Who we are esurance is a Swiss InsurTech offering a SaaS platform that connects SMEs, insurance providers, brokers, and business application providers. Founded in 2013, we're on a mission to make health insurance for small businesses truly hassle-free. What makes us unique You'll be part of a connected, forward-thinking team built on trust, openness, and mutual respect — working hybrid from Zürich or remotely across Europe. We invest in your growth through agile practices, real ownership, and a transparent Grading System that ensures fair pay and clear career paths. Our core values We are connected. We are ahead. We are clear. We are approachable. Do these resonate with you? → Come join us. Our Recruitment Process & Principles We keep our process transparent and respect your time: Application Review — You hear from us within 5 business days. Always. Recruiter Screen — A relaxed Get2Know call to explore mutual fit. Four Interviews — Two Role Knowledge interviews (peer + supervisor), one Culture Match, one Leadership conversation. Batched into two days wherever possible. Hiring Decision — Thoughtful, timely. You'll know within 1–2 weeks. Use of Artificial Intelligence (AI) We use AI to increase productivity and you're welcome to use it to polish your CV or Coverletter. Interviews and assessments should reflect your genuine self, though. Recruiting Agencies: We don't work with unsolicited agency submissions. Thanks for respecting this.

🏢 Summary: Senior Full Stack Developer role for an international product team focused on building scalable applications using TypeScript, React, Node.js, PostgreSQL, and Kafka. The contract is remote, B2B, initially for 6 months with possible extension, and includes collaboration in an agile international environment with AI-powered development tools. 🗂️ Requirements: 8+ years of commercial software development experience, Strong TypeScript experience, Experience with React, Experience with Node.js, Experience with NestJS, Knowledge of PostgreSQL, Knowledge of REST APIs, Knowledge of Kafka, Experience building scalable systems, Daily use of AI coding tools, English level B2+/C1 📃 Skills: TypeScript, React, Node.js, NestJS, PostgreSQL, REST, Kafka, Claude, Cursor, Codex, Copilot 🏢 Description: co.brick talents — powered by AI, powered by people. Senior Full Stack Developer (TypeScript / React / Node.js) Location: Remote Contract: B2B Rate: Up to 150–160 PLN/hour Duration: 6 months with a strong possibility of extension Start: ASAP About the project We are looking for an experienced Senior Full Stack Developer to join an international product development team. You will work on building and enhancing scalable software solutions in a modern technology stack, collaborating with experienced engineers in an agile environment. Your responsibilities Design, develop, and maintain scalable full stack applications. Build high-quality backend services and modern frontend solutions. Develop and integrate REST APIs. Work with PostgreSQL and Kafka-based architectures. Collaborate with cross-functional, international teams. Apply AI-powered coding tools to improve development efficiency and code quality. Requirements 8+ years of commercial software development experience. Strong experience with TypeScript on both the frontend and backend. Hands-on experience with React and Node.js/NestJS . Solid knowledge of PostgreSQL , REST APIs , and Kafka . Experience designing and building scalable systems or software products. Daily use of AI coding tools such as Claude Code, Cursor, Codex, GitHub Copilot , or similar ( must have ). Very good English communication skills ( B2+/C1 , must have ). Nice to have Experience building SaaS products. Experience developing on-premise software solutions. Recruitment process The recruitment process includes a technical assignment (approximately 5 hours) . During the task, you are welcome and encouraged to use AI coding tools , as we value modern software development practices.

🏢 Summary: Senior FullStack .NET Developer role focused on building and scaling cloud-native FinTech products across backend microservices and modern React frontends. The position involves end-to-end feature ownership, architectural contributions on Azure, and development of high-performance, user-centric web applications. It combines distributed systems engineering with product-driven development in a fast-paced environment. 🗂️ Requirements: 5+ years experience with .NET (6/8+) and C#, Strong experience building RESTful APIs, Experience with event-driven architectures, Solid experience with React and TypeScript, Experience with state management libraries (Redux, Zustand, or React Query), Practical experience with Azure (App Services, Functions, Service Bus, Cosmos DB/SQL), Strong knowledge of SQL Server, Experience with Entity Framework Core, Hands-on experience with Docker and Kubernetes, Experience with CI/CD pipelines (Azure DevOps or GitHub Actions), Experience working with microservices architecture 📃 Skills: .NET, C#, React, TypeScript, Azure, SQL, SQLServer, EntityFramework, Docker, Kubernetes, CI/CD, REST, Microservices, Redux, Zustand, ReactQuery, ServiceBus, CosmosDB, GitHubActions, AzureDevOps 🏢 Description: About Optiveum and our Client Optiveum is a boutique talent advisory firm. We help our clients build high-performance technology teams that move the needle. We are currently looking for a Senior FullStack .NET Developer for our client—a fast-growing US-based leader in the Financial Technology sector . With a major engineering hub in Warsaw , they are blending American innovation and "move-fast" culture with top-tier Polish engineering talent. You’ll be joining an environment that skips the bureaucracy in favor of high ownership, architectural excellence, and a product-first mindset. The Role As a Senior FullStack Engineer, you aren’t just executing tickets; you are a product builder . You will bridge the gap between robust, high-scale backend services and modern, highly interactive user interfaces. This role is perfect for someone who thrives in a fast-paced US tech culture, enjoys solving complex distributed systems puzzles, and cares deeply about delivering a world-class User Experience (UX). Your Responsibilities Full-Scale Development: Own features end-to-end, from database schema and API design to the final React component. Architecture & Scale: Contribute to the evolution of a Cloud-Native microservices architecture on Azure, designed to handle global traffic. Engineering Excellence: Maintain high standards (SOLID, Clean Code, Design Patterns) while maintaining the velocity needed for a competitive US market. Frontend Leadership: Drive the development of responsive, high-performance web applications using React. Global Collaboration: Partner closely with US-based Product Managers and Stakeholders to translate vision into scalable technical reality. Mentorship: Lead by example through Code Reviews and knowledge sharing, helping elevate the Warsaw engineering hub. Requirements Backend Expertise: 5+ years of experience in .NET (.NET 6/8+) and C#. Expertise in building RESTful APIs and event-driven architectures. Frontend Mastery: Solid experience with React and TypeScript . Familiarity with state management (Redux, Zustand, or React Query). Cloud-Native Mindset: Practical experience with Azure (App Services, Functions, Service Bus, Cosmos DB/SQL). Database Knowledge: Strong skills in SQL Server and Entity Framework Core. Modern DevOps: Hands-on experience with Docker, Kubernetes, and CI/CD pipelines (Azure DevOps/GitHub Actions). Language: Good English Nice to Have Experience in high-growth FinTech, WealthTech, or high-frequency trading environments. Knowledge of testing frameworks (xUnit, Jest/Cypress). Familiarity with Web Performance optimization and Accessibility (WCAG). What We Offer US Tech Culture: A transparent, high-growth environment that values "radical candor," innovation, and taking initiative. Professional Growth: Access to the latest tech—we operate on the "bleeding edge" of .NET and React. Modern Warsaw Office: A vibrant, well-located hub for collaboration, combined with a flexible hybrid/remote policy. Competitive Compensation: 18.000 - 25000 PLN B2B Global Scale: Your code will power mission-critical systems used by financial professionals and institutions across the US and globally.