Senior FullStack Developer

🏢 Summary: Senior Software Engineer role focused on developing and maintaining a complex enterprise .NET platform, combining backend development, production troubleshooting, and performance optimization. The position involves working on identity-related systems and improving architecture, reliability, and code quality within a large-scale environment. The engineer will contribute to technical decisions and future platform evolution. 🗂️ Requirements: 5+ years commercial experience with C# and .NET, Strong knowledge of ASP.NET Core, Experience with asynchronous programming, Experience with dependency injection, Hands-on experience with Entity Framework Core, Strong understanding of SQL Server, Experience with query optimization, Experience with OAuth2, Experience with OpenID Connect, Experience with JWT, Experience supporting and troubleshooting production systems, Fluent English 📃 Skills: C#, .NET, ASP.NET, EntityFramework, SQLServer, OAuth2, OpenIDConnect, JWT, IdentityServer, Duende, ActiveDirectory, AzureAD, MicrosoftGraph, Quartz.NET, SignalR, Playwright, AzureDevOps, CI/CD 🏢 Description: We are looking for an experienced Senior Software Engineer to develop and maintain a complex enterprise .NET platform used by global organizations. This role combines backend development , production troubleshooting , performance optimization , and work on identity-related systems . 💼 Responsibilities: Design, develop, and maintain backend services built with C# and .NET Investigate and resolve complex production issues and customer-reported problems Optimize application performance, database queries, and system reliability Collaborate with Product, Support, and Engineering teams on technical solutions Improve architecture, code quality, and engineering standards Participate in technical discussions and contribute to future platform development ✅ Requirements: 5+ years of commercial experience with C# and .NET Strong knowledge of ASP.NET Core and modern .NET applications Experience with asynchronous programming and dependency injection Hands-on experience with Entity Framework Core Good understanding of SQL Server, query optimization, and database performance Experience with OAuth2, OpenID Connect, JWT Experience supporting and troubleshooting production systems Fluent English communication skills 🌟Nice to have: Experience with IdentityServer / Duende IdentityServer Understanding of Active Directory, Azure AD or Microsoft Graph Hands-on experience with Quartz.NET or similar scheduling frameworks Familiarity with SignalR, Playwright, Azure DevOps and CI/CD pipelines 🎁 We offer: Work on a mature enterprise product used globally Influence technical decisions and platform evolution Private healthcare Life insurance Multisport Opportunity to work with modern .NET technologies and large-scale systems

🏢 Summary: Senior full-stack role focused on building and maintaining scalable applications using .NET and React in Microsoft Azure. The position involves designing cloud-based solutions, contributing to architecture decisions, and ensuring high code quality, testing, and CI/CD practices within an Agile environment. 🗂️ Requirements: 4+ years commercial experience with .NET (C#, .NET/.NET Core, Entity Framework or other ORM, WCF), 3+ years experience with React (or Angular with recent React), 2+ years experience with Microsoft Azure services, Experience with REST or SOAP web services and APIs, Strong knowledge of software architecture and design patterns, Experience with Clean Code principles and Unit Testing, Solid knowledge of SQL, Experience with Git and CI/CD pipelines, Experience with automated deployments, Fluent English 📃 Skills: C#, .NET, .NETCore, EntityFramework, WCF, React, Angular, Azure, AzureFunctions, AzureLogicApps, AzureWebApps, AzureSQL, SQLServer, REST, SOAP, SQL, Git, CI/CD, UnitTesting 🏢 Description: Role Overview We are looking for a Senior .NET Developer with strong experience in React and Microsoft Azure to join our team. In this role, you will work on designing and developing modern full-stack applications, applying best engineering practices and delivering scalable solutions in a cloud environment. You will collaborate closely with cross-functional teams, contribute to architecture decisions, and ensure high standards of code quality, testing, and continuous delivery. Key Responsibilities Design, develop, and maintain full-stack applications using .NET technologies and React . Apply object-oriented and functional programming principles to solve real-world engineering challenges. Write clean, maintainable, and well-tested code following established software design patterns and best practices. Develop and deploy solutions in Microsoft Azure cloud environments . Participate in Agile software development processes , including sprint planning, reviews, and retrospectives. Implement and maintain CI/CD pipelines to enable efficient and reliable software delivery. Collaborate with architects, developers, and stakeholders to design scalable and high-quality solutions. Skills & Attributes for Success Strong ability to write clean, readable, and maintainable code aligned with established design patterns and coding standards. Passion for continuous learning and exploring new technologies, especially within the Azure ecosystem . Strong analytical and problem-solving skills. Ability to work effectively in a collaborative and Agile team environment. Required Qualifications 4+ years of commercial experience with .NET technologies (C#, .NET / .NET Core, Entity Framework or other ORM, WCF). 3+ years of experience with React (Angular experience combined with recent React experience is also acceptable). 2+ years of experience with Microsoft Azure services , such as: Azure Functions Azure Logic Apps Azure Web Apps Azure SQL / SQL Server Experience working with web services and APIs (REST / SOAP). Strong knowledge of software architecture and design patterns . Experience with Clean Code principles and Unit Testing . Solid knowledge of SQL . Experience with source code management (Git) and CI/CD pipelines , including automated deployment. Fluent English (both written and spoken).

🏢 Summary: Senior full-stack .NET Developer role focused on building scalable applications using .NET, Angular, and Microsoft Azure. The position involves designing cloud-based solutions, contributing to architecture decisions, and ensuring high code quality with modern engineering practices. Work includes CI/CD implementation and collaboration within Agile teams. 🗂️ Requirements: 4+ years commercial experience with .NET (C#, .NET/.NET Core, Entity Framework or other ORM, WCF), 3+ years experience with Angular (or React with recent Angular), 2+ years experience with Microsoft Azure services, Experience with REST or SOAP web services and APIs, Knowledge of software architecture and design patterns, Experience with Unit Testing and Clean Code principles, Strong SQL knowledge, Experience with Git and CI/CD pipelines, Experience with automated deployments, Fluent English 📃 Skills: C#, .NET, .NETCore, Angular, Azure, EntityFramework, WCF, SQL, REST, SOAP, Git, CI/CD, AzureFunctions, AzureLogicApps, AzureWebApps, AzureSQL, SQLServer 🏢 Description: Role Overview We are looking for a Senior .NET Developer with strong experience in Angular and Microsoft Azure to join our development team. In this role, you will work in a full-stack capacity, building scalable applications and cloud-based solutions while applying modern software engineering practices. You will collaborate with cross-functional teams, contribute to architecture decisions, and ensure high standards of code quality, testing, and continuous delivery. Key Responsibilities Design, develop, and maintain full-stack applications using .NET technologies and Angular . Apply object-oriented and functional programming principles to solve complex software engineering challenges. Write clean, maintainable, and well-tested code following recognized software design patterns and best practices. Develop and deploy solutions using Microsoft Azure services . Work in Agile development environments , contributing to sprint planning, reviews, and continuous improvement. Implement and support CI/CD pipelines to enable efficient and reliable software delivery. Collaborate with architects, developers, and stakeholders to design scalable and high-quality solutions. Skills & Attributes for Success Strong ability to write clean, readable, and maintainable code aligned with established coding standards. Solid understanding of software design patterns and architecture principles . Passion for continuous learning and exploring new technologies, particularly within the Azure ecosystem . Strong analytical and problem-solving skills. Ability to work effectively in a collaborative Agile environment. Required Qualifications 4+ years of commercial experience with .NET technologies (C#, .NET / .NET Core, Entity Framework or other ORM, WCF). 3+ years of experience with Angular (React experience combined with recent Angular experience is also acceptable). 2+ years of experience with Microsoft Azure services , such as: Azure Functions Azure Logic Apps Azure Web Apps Azure SQL / SQL Server Experience working with web services and APIs (REST / SOAP). Good knowledge of software architecture and design patterns . Experience with Clean Code principles and Unit Testing . Solid knowledge of SQL . Experience with Git , CI/CD pipelines , and automated deployment processes. Fluent English (spoken and written).

🏢 Summary: Senior Full Stack Engineer role focused on building and optimizing React/TypeScript frontends and ASP.NET Core backend services supporting treasury workflows. The position involves designing scalable REST APIs, improving performance across the stack, and working with large datasets in production systems. Hybrid work model in Warsaw with strong emphasis on engineering best practices and reliability. 🗂️ Requirements: 5+ years of experience building production systems, Strong experience with C# and .NET ecosystem, Strong experience with ASP.NET Core, Strong experience with React, Strong experience with TypeScript, Experience designing and building REST APIs, Experience handling large datasets efficiently, Hands-on experience with ag-Grid, Highcharts or similar libraries, Understanding of authentication and authorization mechanisms, Experience with relational databases, Experience with performance optimization 📃 Skills: C#, .NET, ASP.NETCore, React, TypeScript, REST, ag-Grid, Highcharts, SQL, CI/CD, Authentication, Authorization, Serialization 🏢 Description: Senior Full Stack Engineer (.NET / React) Warsaw, hybrid, 3 days per week from the office. Responsibilities Build and enhance frontend applications and backend services supporting treasury workflows. Develop React/TypeScript single‑page applications and reusable UI components. Design and implement ASP.NET Core REST APIs with scalable pagination and filtering models. Optimize performance across the stack, including APIs, serialization, rendering, and large data grids. Collaborate with business stakeholders, quant teams, and product managers to deliver user‑focused solutions. Drive engineering best practices including code reviews, testing, CI/CD, and production support. Investigate production issues and improve observability and platform reliability. Mentor engineers and contribute to technical growth within the Warsaw team. Requirements 5+ years of software engineering experience building production systems. Strong experience with C#/.NET ecosystem and ASP.NET Core . Strong frontend experience with React and TypeScript. Experience building REST APIs and handling large datasets efficiently. Hands‑on experience with ag‑Grid, Highcharts, or similar UI/data visualization libraries. Strong understanding of authentication, authorization, and serialization mechanisms. Experience working with relational databases and performance optimization. Strong communication skills and ability to work directly with business stakeholders. Nice to Have Experience in treasury, trading, or financial systems. Strong product mindset and UX awareness.

🏢 Summary: The offer is for a Senior .NET Developer with 5+ years of experience to design, develop, and maintain scalable backend applications using modern .NET technologies. The role focuses on building high-quality APIs, contributing to architectural decisions, and ensuring application reliability in cloud-based environments. It involves close collaboration with cross-functional teams and strong engagement in testing, CI/CD, and production support. 🗂️ Requirements: Minimum 5 years of experience with .NET development, Strong experience with C# and .NET Core, Solid understanding of REST APIs, Experience with Entity Framework Core, Strong knowledge of SQL, Experience with cloud platforms (Azure or AWS), Experience with CI/CD pipelines, Experience with Git version control, Experience with unit and integration testing, Experience with message broker systems, Familiarity with agile development practices 📃 Skills: C#, .NET, .NETCore, REST, EntityFramework, SQL, Azure, AWS, CI/CD, Git, UnitTesting, IntegrationTesting, MessageBroker, Angular, Docker, Kubernetes, Microservices 🏢 Description: Summary: We’re looking for a highly skilled .NET Developer with a minimum of 5 years of experience. This role focuses on solving complex problems, building high-quality software, and contributing to a collaborative engineering culture. The candidate should be passionate about clean architecture, modern .NET development, and delivering impactful solutions. Responsibilities: - Analyze, design, develop, and maintain applications using .NET / .NET Core. - Build scalable backend services (APIs). - Collaborate with cross-functional teams (Business, Dev, Infra, etc.). - Participate in code reviews to elevate engineering standards. - Contribute to architectural decisions and technical roadmaps. - Provide business support and monitor applications (level 2 support, incident resolution, and troubleshooting). Key Requirements: - Strong experience with C# and .NET Core. - Solid understanding of REST APIs, Entity Framework Core, and SQL. - Familiarity with cloud platforms (Azure or AWS). - Experience with CI/CD pipelines and version control (Git). - Strong testing culture: unit tests, integration tests, and production validation. - Familiarity with agile development practices. - A mindset focused on quality, performance, and maintainability. - Experience with a message broker. Nice to Have: - Knowledge of microservices architecture. - Experience with front-end frameworks (Angular). - Background in distributed systems or high-availability environments. - Knowledge of Docker & Kubernetes. - Experience with Azure functions. Other Details: This position allows for flexibility and may accommodate remote work arrangements. Candidates should be prepared for collaborative team engagements with a focus on delivering high-quality software solutions.

🏢 Summary: The role involves developing and maintaining scalable full-stack web applications using .NET and modern frontend frameworks. You will design robust Web APIs, optimize databases, and implement clean, testable code within CI/CD-driven environments. The position requires active participation in the full software development lifecycle for international projects. 🗂️ Requirements: Minimum 3 years commercial experience with .NET (C#, Web API, Entity Framework), Proficiency in Angular or React, Strong knowledge of JavaScript, HTML, CSS, Experience with SQL Server or PostgreSQL, Understanding of Unit Testing, Experience with Git, Experience with CI/CD pipelines, Knowledge of design patterns, Knowledge of software development best practices, Fluent English (min. B2), Availability for hybrid work mode 📃 Skills: .NET, C#, WebAPI, EntityFramework, Angular, React, JavaScript, HTML, CSS, SQL, SQLServer, PostgreSQL, UnitTesting, Git, CI/CD 🏢 Description: As a member of our development team, you will be responsible for building scalable web applications, designing robust APIs, and creating intuitive user interfaces. We value clean code, analytical thinking, and a proactive approach to technology. Our expectations: Minimum 3 years of commercial experience in .NET (C#, Web API, Entity Framework). Proficiency in Angular or React, along with JavaScript, HTML, CSS, and modern frontend libraries. Strong experience with relational databases such as SQL Server or PostgreSQL. Solid understanding of Unit Testing, Git, and CI/CD pipelines. Practical knowledge of design patterns and software development best practices. A collaborative mindset and the ability to explain complex technical issues clearly. Strong analytical skills and a "get it done" attitude. Fluent English (min. B2) for smooth collaboration with international partners. Open to work in hybrid mode. Main responsibilities: You will design, develop, and maintain scalable full-stack applications using .NET and modern frontend frameworks (Angular/React) for diverse client projects. You will be responsible for writing clean, testable code and implementing unit tests to ensure the highest software performance and reliability. You will work closely with cross-functional teams to architect robust Web APIs and optimize database schemas while following industry best practices and design patterns. You will actively participate in the full software development life cycle, including CI/CD processes and version control management, to ensure seamless project delivery.

🏢 Summary: The role involves developing and maintaining an enterprise-grade web application within the .NET ecosystem, with a strong focus on backend development and system architecture. You will design and enhance REST APIs, implement business logic, and integrate modern .NET Core solutions with legacy .NET Framework components. The position emphasizes scalable architecture, database optimization, and high code quality through comprehensive testing. 🗂️ Requirements: 5+ years of experience in .NET development, Strong expertise in .NET Core and backend systems, Experience designing and building REST APIs, Hands-on experience with Entity Framework Core, Experience with relational databases, especially SQL Server, Understanding of software architecture and design patterns, Experience working with .NET Framework 4.8, Experience with unit, integration, and end-to-end testing, Ability to integrate and maintain backend services, Basic knowledge of React or experience collaborating with frontend teams 📃 Skills: .NET, C#, ASP.NET, REST, Swagger, OpenAPI, EntityFramework, SQLServer, SQLite, React, xUnit, NUnit, AI, Copilot, ChatGPT 🏢 Description: Additional information The project focuses on the development and maintenance of an enterprise-grade web application built on the .NET ecosystem, with a strong emphasis on backend and system architecture. The main responsibility is to design and enhance REST APIs and business logic , including integration with existing components based on .NET Framework 4.8. The system relies on relational databases (SQL Server) and ORM solutions such as Entity Framework Core, with a strong focus on quality through multi-level testing. The role also involves collaboration with the frontend layer (React), although it is not the primary focus. The environment requires a high level of autonomy, technical decision-making, and a proactive approach to improving the existing architecture. You’re ideal for this role if you: Have 5+ years of experience in .NET development, with strong expertise in .NET Core and backend systems Are confident in designing and building REST APIs, including architecture and best practices (e.g., Swagger/OpenAPI) Have hands-on experience with Entity Framework Core and relational databases such as SQL Server Understand software architecture, design patterns, and how to build scalable, maintainable systems Are familiar with legacy environments, including .NET Framework 4.8, and can work across modern and existing solutions Have solid experience with testing (unit, integration, end-to-end) and care about code quality Have basic knowledge of React or are comfortable working closely with frontend teams Use AI tools (e.g., Copilot, ChatGPT) to improve development efficiency Take ownership of your work and proactively identify improvements rather than waiting for tasks Your day-to-day responsibilities include:​ Designing, developing, and maintaining backend services using .NET Core Building and enhancing REST APIs, ensuring performance, scalability, and clear documentation (Swagger/OpenAPI) Integrating new features with existing systems based on .NET Framework 4.8 Implementing business logic and ensuring consistency across application layers Working with databases (SQL Server, SQLite) and optimizing data access with Entity Framework Core Writing and maintaining tests (unit, integration, end-to-end) to ensure high code quality Collaborating with frontend developers (React) to ensure smooth end-to-end functionality Participating in architectural discussions and contributing to technical decisions Identifying areas for improvement and proactively proposing enhancements Using AI tools to streamline development and increase productivity

🏢 Summary: Senior Backend Engineer role focused on building and scaling a cloud-based SaaS platform using modern .NET services and REST APIs. The position involves designing distributed systems, improving reliability and observability, and working with cloud and container environments. You will contribute to technical decisions and engineering best practices within a collaborative team. 🗂️ Requirements: 5+ years backend development experience, Experience with SaaS and web applications, Strong knowledge of C#, Strong knowledge of modern .NET/.NET Core, Solid computer science fundamentals, Experience with distributed systems design, Experience with cloud platforms, Experience with containers and orchestration, Understanding of concurrency and performance, Knowledge of authentication and authorization mechanisms 📃 Skills: C#, .NET, .NETCore, REST, Azure, AWS, GCP, Kubernetes, Kafka, RabbitMQ, SQS, Docker, SQL, HTML, CSS, JavaScript 🏢 Description: We’re hiring a Senior Backend Engineer to help build and scale a cloud-based SaaS platform. You’ll work on modern .NET services and APIs, improve reliability and observability, and contribute to technical decisions as part of a collaborative engineering team. Responsibilities: Build and maintain backend services and REST APIs in C# / .NET (.NET Core). Design scalable solutions for distributed systems (async workflows, messaging, integrations). Work with cloud services (Azure/AWS/GCP) and container environments (e.g. Kubernetes). Strengthen system reliability with logging, metrics, tracing, and monitoring. Support secure access patterns: authentication/authorization, API gateway concepts. Contribute through code reviews, good engineering practices, and automation. Requirements: 5+ years of backend development experience, including SaaS and web applications. Strong knowledge of C# and modern .NET + solid CS fundamentals. Familiarity with containers/orchestration and cloud-native approaches. Experience with some of: Kafka/RabbitMQ/SQS, workflow orchestration, job scheduling, search. Good understanding of concurrency and performance. Strong communication skills; Agile/Scrum is a plus. Bonus: basic front-end knowledge (HTML/CSS/JS).

🏢 Summary: Senior Full Stack Developer role focused on designing, building, and enhancing enterprise-level applications using .NET and React. The position involves contributing to architecture decisions, improving performance and usability, and ensuring application reliability across the full technology stack. It includes ownership of backend services, frontend development, CI/CD processes, and production support. 🗂️ Requirements: Minimum 5 years of professional experience in .NET application development, Strong proficiency in C# and Web API, Hands-on experience with React for web application development, Advanced knowledge of SQL Server and database architecture, Experience with CI/CD pipelines, Understanding of Software Development Life Cycle, Proficiency in HTML5 and CSS, Experience in system architecture and design patterns, Ability to troubleshoot production issues 📃 Skills: .NET, C#, WebAPI, React, SQL, SQLServer, CI/CD, HTML5, CSS, SDLC 🏢 Description: We Are Hiring: Senior Full Stack Developer (.NET and React) We are seeking an experienced Full Stack Developer who is ready to play a key role in designing, building, and improving enterprise-level applications. This position is ideal for someone who enjoys working across the entire technology stack, contributing to architectural decisions, enhancing user experiences, and ensuring application reliability and performance. This is a senior-level opportunity for a professional who combines deep technical expertise with strong analytical thinking and a proactive mindset. Key Responsibilities Contribute to system architecture planning and technical design discussions Drive user interface enhancements to improve usability, performance, and overall application resilience Apply industry-recognized design principles and architectural patterns when implementing solutions Review and interpret business and technical requirements, proposing improvements where appropriate Produce clear and detailed technical documentation for developed features and systems Build proof-of-concept solutions and prototypes to validate architectural approaches Oversee and manage system modifications within structured service management processes Support and enhance automation initiatives across development and operational workflows Deliver high-quality technical support, ensuring timely resolution of issues Collaborate closely with stakeholders to understand objectives and provide effective solutions Required Qualifications and Experience A minimum of Five years of professional experience developing and maintaining production-grade applications within the .NET ecosystem Strong proficiency in C# and Web API development, with experience building secure, scalable, and high-performing backend services Solid hands-on experience with React, developing dynamic, responsive, and performance-optimized web applications Advanced knowledge of database architecture and SQL Server, including complex query development, performance optimization, and tuning Practical experience with continuous integration and continuous delivery pipelines Comprehensive understanding of the Software Development Life Cycle, from requirements analysis through deployment and ongoing support Strong command of modern web standards including HTML5 and Cascading Style Sheets, with the ability to create intuitive user interfaces Excellent analytical and troubleshooting abilities, particularly in demanding production environments High attention to detail and commitment to delivering robust, maintainable solutions If you are passionate about developing high-quality software, improving system performance, and contributing to meaningful technical decisions, we would welcome the opportunity to connect with you. Please feel free to reach out directly or share this opportunity within your professional network. #Hiring #FullStackDeveloper #DotNet #React #SoftwareEngineering #TechnologyCareers

🏢 Summary: Senior Full-Stack Developer role focused on enhancing a platform using React and TypeScript on the frontend and .NET/C# with SQL Server on the backend. The position emphasizes strong frontend expertise while maintaining sufficient backend knowledge for independent task execution. Experience with legacy systems is considered an advantage. 🗂️ Requirements: 5+ years full-stack development experience (Mid) or 10+ years (Senior), Proficiency in React, Proficiency in TypeScript, Strong knowledge of modern JavaScript, Solid knowledge of C# and .NET, Ability to work with SQL Server 📃 Skills: React, TypeScript, JavaScript, C#, .NET, SQL, SQLServer, ClassicASP 🏢 Description: Summary: A senior full-stack developer position focused on enhancing our platform through modern technologies, primarily using React and TypeScript on the frontend and .NET/C# with SQL Server on the backend. Main Responsibilities: Strengthen the focus on React and TypeScript as the primary and most critical skills, with a solid foundation in modern JavaScript. Utilize .NET/C# and SQL Server as supporting skills to ensure self-sufficiency in day-to-day tasks without primary responsibility for complex backend or database optimization. Leverage knowledge of legacy technologies, such as Classic ASP, for understanding existing logic as a nice-to-have skill. Key Requirements: At least 5 years of experience (Mid-level) or 10 years (Senior-level) in full-stack development. Proficiency in React and TypeScript. Solid foundation in modern JavaScript and C# / .NET. Nice to Have: Experience with legacy systems like Classic ASP.