Senior C# Developer

🏢 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)

🏢 Summary: Senior Full-Stack Engineer role focused on building scalable ASP.NET/C# microservices and React/TypeScript interfaces, with a 60/40 frontend-to-backend split. The position offers technical ownership, mentoring opportunities, and a potential path to Tech Lead while working hybrid from Poland under an employment contract. 🗂️ Requirements: Poland residency, MSc in Computer Science or equivalent, 5+ years building secure REST APIs with ASP.NET, 5+ years developing frontend applications with React, Microservices architecture expertise, Cloud design-pattern knowledge, Technical ownership, Technical leadership, English B2 fluency 📃 Skills: ASP.NET, C#, React, TypeScript, REST, Microservices, Cloud, AWS, Agile, DDD 🏢 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 60/40 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) Polish and German: 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: 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.