.Net Developer

🏢 Summary: B2B opportunity for an experienced .NET Back-End Developer to build modern, scalable cloud-based solutions using C# and Azure. The role focuses on designing high-performance services, working with CosmosDB, and collaborating in an Agile team with exposure to AI-assisted development tools. This is a fully remote position with competitive hourly rates and long-term cooperation. 🗂️ Requirements: 5+ years of professional experience in .NET development, Strong experience with C#, Proven experience with Azure services, Experience with CosmosDB, Experience with TypeScript or JavaScript, Bachelor’s degree in Computer Science or related field, Ability to align with US-based team working hours, English language proficiency 📃 Skills: .NET, C#, Azure, CosmosDB, TypeScript, JavaScript, AI, Playwright, Selenium, Drupal 🏢 Description: For our client from the technology and industrial solutions sector, we are looking for a .NET Back-End Developer to join a talented development team working on modern, scalable software solutions. Responsibilities: Design, develop, and maintain high-performance back-end services using .NET and C#. Work extensively with Azure cloud services and CosmosDB to build scalable and resilient solutions. Collaborate with front-end developers, product owners, and other team members to integrate back-end services. Participate in code reviews, architectural discussions, sprint planning, and other Agile ceremonies. Use modern development tools and practices to improve productivity, code quality, and maintainability. Explore and apply AI-assisted tools where appropriate to support development, documentation, troubleshooting, and workflow efficiency. Contribute to improving development processes, engineering practices, and team knowledge sharing. Be a proactive problem-solver and continuous learner, staying current with relevant technologies and industry trends. Requirements: Application Development Experience: 5+ years of professional experience in .NET development. Cloud Development Expertise: Proven experience with C#, Azure services, and CosmosDB. Scripting / Front-End Knowledge: Experience with TypeScript preferred, or JavaScript. AI Tool Familiarity: Interest in or hands-on experience using AI tools to support software development, productivity, documentation, research, or troubleshooting. Educational Background: Bachelor’s degree in Computer Science or a related field. Flexibility: Ability to align somewhat with US-based team working hours. Communication: English language proficiency. Stack: Cloud: Azure, CosmosDB Back-End: .NET, C# Scripting / Tooling: TypeScript preferred, JavaScript acceptable Productivity / AI Tools: Familiarity with AI-assisted development or productivity tools is a plus Nice to have: Domain Knowledge: Background in Electrical Engineering or a related technical field. Background or interest in analog and mixed-signal hardware design. Knowledge of hardware or system simulation concepts. CMS Knowledge: Familiarity with Drupal. Test Automation Exposure: Familiarity with tools like Playwright or Selenium. Quality Mindset: Prior QA experience or understanding of QA methodologies is welcome. Offer: Cooperation based on a B2B contract and rate: 140-170 PLN/hour 100% remote work The support of a dedicated mentor. In the relationship, we focus on direct communication. When you join speedapp, you will be put in touch with a dedicated mentor who will make sure that you enjoy working with us and with the client. Events and integration meetings, as well as participation in various initiatives, e.g., sports. Access to the benefits offering (medical care, Multisport card). About Speedapp At speedapp, we believe that an organization is only as good as the people who make it up. We are a team of IT experts and other professionals working for our clients around the world (including Israel, Austria, USA). We go far beyond the HR category. We build IT teams and also help manage them. 👉 10 years of experience 👉 +100 clients worldwide +300 hires per year 💎 We have won the prestigious "Forbes Diamonds" award four times (2022, 2023, 2024, 2025). We are a member of the European Fast Growth Icons network and FinTech Poland. We are ranked 18th among the 100 fastest growing companies 2023 by Clutch.

🏢 Summary: B2B contract for an experienced .NET Developer to build and maintain backend systems for online and mobile banking. The role focuses on developing a transactional system in a microservices architecture with high scalability, performance, and security standards. Work is delivered in a SCRUM environment with a hybrid model in Warsaw. 🗂️ Requirements: Minimum 5 years of .NET experience, Strong knowledge of C#, Strong knowledge of .NET Core, Strong knowledge of Entity Framework, Knowledge of microservices architecture, Knowledge of REST, Knowledge of SQL, Database query optimization, Unit testing knowledge, Application security knowledge, Distributed systems architecture knowledge, English B2 level, Higher education degree 📃 Skills: .NET, C#, .NetCore, EntityFramework, REST, SQL, Microservices, SCRUM, UnitTesting, Security, DistributedSystems, English 🏢 Description: Dla klienta z branży bankowej i finansowej poszukujemy doświadczonego .NET Developera, który dołączy do zespołu odpowiedzialnego za rozwój i utrzymanie systemów backendowych. ZADANIA Rozwój bankowości internetowej oraz mobilnej, w szczególności: Rozwiązywanie problemów związanych ze skalowalnością, wysoką wydajnością i dostępnością systemów. Rozwój systemu transakcyjnego opartego na architekturze mikroserwisowej. Tworzenie oprogramowania zgodnego ze standardami bezpieczeństwa. Praca z użyciem metodologii SCRUM. WYMAGANIA Minimum 5 lat doświadczenia w programowaniu .NET. Bardzo dobra znajomość C#, .Net Core, Entity Framework. Znajomość architektury mikroserwisowej oraz REST. Znajomość SQL oraz sposobów optymalizacji zapytań bazodanowych. Znajomość zagadnień związanych z pisaniem testów jednostkowych. Znajomość zagadnień związanych z bezpieczeństwem aplikacji. Zagadnienia architektury rozproszonej. Znajomość języka angielskiego w piśmie i mowie (min. B2). Wykształcenie wyższe. MILE WIDZIANE Znajomość: Apache Kafka od strony programistycznej. Redis. Wzorca Domain Driven Design. Zagadnień związanych z optymalizacją aplikacji. Wzorca CQRS. CO OFERUJEMY NA TYM PROJEKCIE? Współpracę w oparciu o umowę B2B i stawkę: 120-130 zł/h. Pracę  hybrydową z Warszawy (1 raz w tygodniu z biura). Wsparcie dedykowanego opiekuna. Po dołączeniu do speedapp, otrzymasz kontakt do dedykowanego opiekuna, który zadba, aby współpraca z nami oraz z klientem sprawiała Ci satysfakcję. Wydarzenia oraz spotkania integracyjne, a także udział w różnych inicjatywach np. sportowych. Dostęp do oferty benefitów (opieka medyczna, karta Multisport). JAK WYGLĄDA REKRUTACJA? Zgłoszenie: Zaaplikuj i prześlij swoje CV. Po weryfikacji aplikacji rekruter skontaktuje się telefonicznie z wybranymi kandydatami. Screening: Porozmawiaj z rekruterem speedapp o Twoim doświadczeniu. Kolejne etapy: Rekruter speedapp przedstawi Ci jak wygląda proces rekrutacji na dane stanowisko. Rekruter speedapp pozostanie z Tobą w kontakcie podczas całego procesu. O SPEEDAPP W speedapp wierzymy, że organizacja jest tak dobra jak tworzący ją ludzie. Jesteśmy zespołem ekspertów IT i innych specjalistów pracujących dla naszych klientów na całym świecie (m.in Izrael, Austria, USA). Wykraczamy daleko poza kategorię HR. Budujemy zespoły IT, a także pomagamy w ich zarządzaniu. 👉 10 lat doświadczenia 👉 +100 klientów na całym świecie +300 zatrudnień rocznie 💎 Jesteśmy laureatem prestiżowej nagrody Diamenty Forbes cztery lata z rzędu (2022, 2023, 2024, 2025), członkiem sieci Fast Growth Icons oraz FinTech Poland.

🏢 Summary: Senior .NET Developer role focused on designing and building a new .NET 8 architecture for high-scale travel-tech products used by millions of users. The position involves developing and deploying internet-scale solutions in a large production environment. The offer includes hybrid work and long-term B2B cooperation. 🗂️ Requirements: 5+ years experience with .NET Core and C#, Strong knowledge of OOP, design patterns, algorithms, data structures, Experience designing and deploying end-to-end internet-scale solutions, Experience with large-scale production environments, Good knowledge of SQL Server, Good knowledge of Redis, Fluent English (written and spoken) 📃 Skills: .NET, C#, .NET8, SQLServer, Redis, OOP, DesignPatterns, Algorithms, DataStructures, CI/CD, Kubernetes, Elasticsearch, NoSQL, Containers 🏢 Description: Join the client's team in the travel-tech industry as Senior .Net  Developer. RESPONSIBILITIES In this role, the infrastructure and platform used daily by millions of travelers worldwide will be designed and built. The focus is on full transparency, continuous improvement, innovation, and maximizing the use of technology. The team will be responsible for designing and developing a new architecture in .NET 8 to support high-scale products. REQUIREMENTS A solid foundation in computer science and strong competencies in object-orienteddesign, design patterns, algorithms, and data structures, with solid developmentexperience in .NET Core / C# - At least 5+ years experience. Thrive in a fast-paced environment, able to adapt and learn new technologies quickly. Hands-on experience designing, developing, and deploying end-to-end solutions for internet-scale problems. Good understanding of SQL Server and Redis. Experience with large-scale production environments. Excellent communication skills, initiative, and teamwork. High level of communication skills (written and verbal) in English NICE TO HAVE Experience in travel tech. Working with CI/CD is an advantage. Experience with containers and Kubernetes. Experience with NoSQL databases (like Elasticsearch) WHAT DO WE OFFER ON THIS PROJECT? Cooperation based on a B2B contract. Hybrid work from Warsaw (2 times a week in the office). The support of a dedicated mentor. In the relationship, we focus on direct communication. When you join speedapp, you will be put in touch with a dedicated mentor who will make sure that you enjoy working with us and with the client. Events and integration meetings, as well as participation in various initiatives, e.g., sports. Access to the benefits offering (medical care, life insurance, Multisport card). WHAT DOES THE RECRUITMENT PROCESS LOOK LIKE? Application: Apply and submit your CV. After the application review, the recruiter will contact selected candidates by phone. Screening: Have a conversation with a speedapp recruiter about your experience. Next steps: The speedapp recruiter will explain the recruitment process for the specific position. The speedapp recruiter will stay in touch with you throughout the entire process. ABOUT SPEEDAPP At speedapp, we believe that an organization is only as good as the people who make it up. We are a team of IT experts and other professionals working for our clients around the world (including Israel, Austria, USA). We go far beyond the HR category. We build IT teams and also help manage them. 👉 10 years of experience 👉 +100 clients worldwide +300 hires per year 💎 We have won the prestigious "Forbes Diamonds" award four times (2022, 2023, 2024, 2025). We are a member of the European Fast Growth Icons network and FinTech Poland. We are ranked 18th among the 100 fastest growing companies 2023 by Clutch. DO YOU HAVE ANY QUESTIONS? Contact the recruiter responsible for this process directly. Aleksandra Mazur Junior IT Delivery Consultant mail@speedapp.pl +48 728 360 029

🏢 Summary: The offer is for a .NET Developer responsible for building and enhancing scalable backend systems and REST APIs for global travel platforms. The role involves contributing to architecture, optimizing performance, and collaborating in an agile environment to deliver reliable, high-quality software. It includes hybrid work, international projects, and professional development opportunities. 🗂️ Requirements: Minimum 3 years of commercial experience with .NET development, Strong knowledge of ASP.NET MVC, Experience developing REST APIs, Experience working in agile software development teams, Good knowledge of MS SQL, Good knowledge of Elasticsearch, Experience with CI/CD tools (Git, TeamCity or similar), Experience writing unit and integration tests, Ability to write clean, maintainable, and well-tested code, Very good English communication skills 📃 Skills: .NET, ASP.NET, MVC, REST, MS SQL, Elasticsearch, Git, TeamCity, CI/CD, UnitTesting, IntegrationTesting, Umbraco, Angular, AWS 🏢 Description: We are looking for a .NET Developer to join our team and help build scalable, high-quality solutions that power our global travel platforms. In this role, you will work on the development and enhancement of backend systems, contribute to architectural decisions, and collaborate with cross-functional teams to deliver reliable and efficient software used by customers worldwide. Your responsibilities Design, develop, and maintain applications using .NET technologies Translate business requirements into scalable and maintainable technical solutions Develop and enhance REST APIs and backend services Maintain, troubleshoot, and improve existing applications Refactor and optimize code to improve performance, scalability, and maintainability Write clean, well-structured, and testable code following best practices Participate in code reviews and contribute to improving development standards Identify and resolve performance bottlenecks and system issues Contribute to application architecture, technical design, and system documentation Collaborate closely with developers, QA engineers, Product Owners, and other stakeholders in an agile environment Our requirements At least 3 years of commercial experience with .NET development Strong knowledge of ASP.NET MVC and REST APIs Experience working within agile software development teams Good knowledge of MS SQL and Elasticsearch Experience with CI/CD tools and practices (Git, TeamCity or similar) Experience writing unit and integration tests Ability to write clean, maintainable, and well-tested code Very good English communication skills Nice to have Experience with Umbraco CMS Experience with Angular Knowledge of AWS services and cloud-based solutions How we work Clean Code principles Design patterns and software engineering best practices Code reviews and knowledge sharing Static code analysis Continuous Integration and Continuous Deployment (CI/CD) Agile and collaborative development environment What we offer Hybrid work model (1–2 days per week in our Katowice office) Opportunity to work on international, large-scale projects Attractive remuneration paid in EUR Flexible working hours Individual development budget Partially or fully funded training and certifications English lessons Mentoring and support from experienced technical leaders Participation in conferences in Poland and abroad A culture focused on learning, collaboration, and knowledge sharing Space to innovate and bring your own ideas to life Support for IT community initiatives

🏢 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 applications within the .NET ecosystem, integrating them with cloud platforms, and supporting DevOps automation processes. The position focuses on building scalable solutions, managing CI/CD pipelines, and implementing Infrastructure as Code in Azure and GCP environments. The developer will collaborate with cross-functional teams to enhance data integration and deployment workflows. 🗂️ Requirements: Strong experience with C#, Strong experience with .NET framework or .NET ecosystem, Experience with Python, Experience with Azure, Experience with GCP, Knowledge of GitHub, Knowledge of GitHub Actions, Knowledge of Azure DevOps, Experience with CI/CD pipelines, Experience with Terraform, Experience with Infrastructure as Code, Fluency in Polish, Fluency in English 📃 Skills: C#, .NET, Python, Azure, GCP, GitHub, GitHubActions, AzureDevOps, CI/CD, Terraform, SQL, Spotfire, Signals 🏢 Description: Role Overview We are looking for a C#/.NET Developer with experience in cloud environments and DevOps practices to join our team. In this role, you will be responsible for developing and maintaining applications built on the .NET ecosystem, integrating them with cloud services, and supporting automation and deployment processes. You will work closely with cross-functional teams to build scalable solutions, integrate data and analytics tools, and improve development workflows through modern DevOps practices. Key Responsibilities Design, develop, and maintain applications using C# and .NET technologies . Support development and automation tasks using Python where appropriate. Work with cloud platforms (Azure and GCP) to deploy and manage applications and services. Implement and maintain DevOps processes , including CI/CD pipelines using GitHub, GitHub Actions, and Azure DevOps (ADO) . Manage infrastructure and environments using Infrastructure as Code tools such as Terraform . Integrate applications with analytics and visualization tools such as Spotfire . Work with Signals .NET framework–based systems to support data integration and application functionality. Collaborate with engineering, data, and DevOps teams to ensure reliable and scalable solutions. Required Skills Strong experience with C# and .NET framework / .NET ecosystem . Experience with Python for scripting, automation, or data-related tasks. Knowledge of DevOps tools and practices , including GitHub, GitHub Actions, and Azure DevOps (ADO) . Experience working with cloud platforms such as Microsoft Azure and Google Cloud Platform (GCP) . Familiarity with Infrastructure as Code , particularly Terraform . Experience working with SQL or data-driven applications is a plus. Good understanding of CI/CD pipelines and automated deployment processes . Polish and English must have Nice to Have Basic knowledge of Spotfire or other analytics/visualization tools. Experience with Signals platform and .NET-based integrations . Experience working in Agile development environments .

🏢 Summary: B2B contract role for a Senior Frontend Developer to architect and build advanced single-page applications in the banking domain. The position focuses on frontend architecture, performance optimization, and integration with backend services using modern web technologies. Hybrid work model with collaboration across cross-functional teams. 🗂️ Requirements: Strong experience with HTML, Strong experience with CSS, Strong experience with JavaScript, Strong experience with TypeScript, Hands-on experience with Web Components, Hands-on experience with Lit, Good knowledge of Node.js, Knowledge of npm ecosystem, Experience with Vitest or similar testing frameworks, Experience integrating REST APIs, Experience integrating GraphQL APIs 📃 Skills: HTML, CSS, JavaScript, TypeScript, WebComponents, Lit, Node.js, npm, Vitest, REST, GraphQL 🏢 Description: We are looking for a Senior Frontend Developer for our client in the banking industry RESPONSIBILITIES Architect and implement advanced user interfaces and single-page applications using TypeScript and JavaScript Define and promote best practices for frontend architecture, state management and reusable components Optimize application performance, including load times and Core Web Vitals, ensuring smooth user experience across devices Collaborate closely with backend developers, UX/UI designers, and product managers Integrate frontend applications with REST and GraphQL APIs Ensure code quality through testing and participation in development lifecycle processes REQUIREMENTS Strong experience with HTML, CSS, JavaScript, and TypeScript Hands-on experience with Web Components / Lit Good knowledge of Node.js and npm ecosystem Experience with testing frameworks such as Vitest NICE TO HAVE Experience with CI/CD pipelines Familiarity with Kafka Knowledge of NinjaFork Experience working with messaging systems (MQ) WHAT DO WE OFFER ON THIS PROJECT? Cooperation based on a B2B contract and rate: 110-120 PLN/hour Hybrid work from Warsaw / Łódź / Gdynia / Gdańsk (3 times a week in the office) The support of a dedicated mentor. In the relationship, we focus on direct communication. When you join speedapp, you will be put in touch with a dedicated mentor who will make sure that you enjoy working with us and with the client Events and integration meetings, as well as participation in various initiatives, e.g., sports Access to the benefits offering (medical care, Multisport card) WHAT DOES THE RECRUITMENT PROCESS LOOK LIKE? Application: Apply and submit your CV. After the application review, the recruiter will contact selected candidates by phone. Screening: Have a conversation with a speedapp recruiter about your experience. Next steps: The speedapp recruiter will explain the recruitment process for the specific position. The speedapp recruiter will stay in touch with you throughout the entire process. ABOUT SPEEDAPP At speedapp, we believe that an organization is only as good as the people who make it up. We are a team of IT experts and other professionals working for our clients around the world (including Israel, Austria, USA). We go far beyond the HR category. We build IT teams and also help manage them. 👉 10 years of experience 👉 +100 clients worldwide +300 hires per year 💎 We have won the prestigious "Forbes Diamonds" award four times (2022, 2023, 2024, 2025). We are a member of the European Fast Growth Icons network and FinTech Poland. We are ranked 18th among the 100 fastest growing companies 2023 by Clutch.

🏢 Summary: The offer is for a .NET Developer to design, develop, and maintain modern web applications and RESTful APIs using Microsoft technologies. The role focuses on ASP.NET Core development, API-first design, Optimizely CMS customization, and ensuring performance, security, and scalability. It also involves contributing to CI/CD processes and reusable component development. 🗂️ Requirements: Strong experience with C# and .NET, Hands-on experience with ASP.NET Core MVC, Experience with Web APIs, Experience designing and consuming REST APIs, Knowledge of OpenAPI/Swagger, Experience with NuGet package management, Experience with Optimizely CMS, Knowledge of JavaScript, Knowledge of TypeScript, Knowledge of HTML, Knowledge of CSS, Experience with Git 📃 Skills: C#, .NET, ASP.NET, MVC, WebAPI, REST, OpenAPI, Swagger, NuGet, Optimizely, Episerver, JavaScript, TypeScript, HTML, CSS, Git, Azure, Docker, React, Angular 🏢 Description: Summary: We are looking for a skilled .NET Developer to support our engineering team in the development and maintenance of modern web applications and APIs. This role is vital for enhancing digital experiences, leveraging Microsoft technologies, and ensuring optimal performance of our systems. Responsibilities: Design, develop, test, and maintain applications using .NET and ASP.NET Core. Develop and enhance RESTful APIs following API-first design principles. Create, maintain, and consume OpenAPI (Swagger) specifications. Build web applications utilizing ASP.NET Core MVC and Web API frameworks. Customize solutions using Optimizely (Episerver) CMS and Commerce platforms. Implement content models and components within Optimizely. Design reusable libraries and manage package publishing through NuGet. Collaborate with architects, product owners, and UX designers to provide quality solutions. Participate in code reviews, testing, and performance optimization. Contribute to CI/CD pipelines and deployment automation. Ensure security, scalability, and reliability in applications. Must Haves: Strong experience with C# and .NET development. Hands-on experience with ASP.NET Core MVC and Web APIs. Experience designing and consuming REST APIs. Strong knowledge of OpenAPI/Swagger specifications. Experience with NuGet package management. Experience with Optimizely (Episerver) CMS. Good knowledge of JavaScript, TypeScript, HTML, and CSS. Experience with Git. Nice to Haves: Experience with Optimizely Commerce and its features. Experience with Azure Cloud Services. Knowledge of Docker. Experience with automated testing frameworks. Understanding of microservices architecture. Familiarity with frontend frameworks like React or Angular.

🏢 Summary: The role involves designing and building high-scale infrastructure and platform solutions in .NET 8 for a global travel-tech product used by millions of users. The position focuses on developing a new architecture for internet-scale systems with an emphasis on innovation and continuous improvement. It includes end-to-end solution design and deployment in large-scale production environments. 🗂️ Requirements: 5+ years of experience with .NET Core and C#, Strong foundation in computer science, Strong knowledge of object-oriented design, Knowledge of design patterns, Knowledge of algorithms and data structures, Experience designing end-to-end solutions for internet-scale systems, Experience with large-scale production environments, Good understanding of SQL Server, Good understanding of Redis, Fluent English (written and verbal) 📃 Skills: .NET, C#, SQL, SQLServer, Redis, Kubernetes, Docker, Elasticsearch, CI/CD, NoSQL 🏢 Description: Join the client's team in the travel-tech industry.. RESPONSIBILITIES In this role, the infrastructure and platform used daily by millions of travelers worldwide will be designed and built. The focus is on full transparency, continuous improvement, innovation, and maximizing the use of technology. The team will be responsible for designing and developing a new architecture in .NET 8 to support high-scale products. REQUIREMENTS A solid foundation in computer science and strong competencies in object-orienteddesign, design patterns, algorithms, and data structures, with solid developmentexperience in .NET Core / C# - At least 5+ years experience. Thrive in a fast-paced environment, able to adapt and learn new technologies quickly. Hands-on experience designing, developing, and deploying end-to-end solutions for internet-scale problems. Good understanding of SQL Server and Redis. Experience with large-scale production environments. Excellent communication skills, initiative, and teamwork. High level of communication skills (written and verbal) in English NICE TO HAVE Experience in travel tech. Working with CI/CD is an advantage. Experience with containers and Kubernetes. Experience with NoSQL databases (like Elasticsearch) WHAT DO WE OFFER ON THIS PROJECT? Cooperation based on a B2B contract. Hybrid work from Warsaw (2 times a week in the office). The support of a dedicated mentor. In the relationship, we focus on direct communication. When you join speedapp, you will be put in touch with a dedicated mentor who will make sure that you enjoy working with us and with the client. Events and integration meetings, as well as participation in various initiatives, e.g., sports. Access to the benefits offering (medical care, life insurance, Multisport card). WHAT DOES THE RECRUITMENT PROCESS LOOK LIKE? Application: Apply and submit your CV. After the application review, the recruiter will contact selected candidates by phone. Screening: Have a conversation with a speedapp recruiter about your experience. Next steps: The speedapp recruiter will explain the recruitment process for the specific position. The speedapp recruiter will stay in touch with you throughout the entire process. ABOUT SPEEDAPP At speedapp, we believe that an organization is only as good as the people who make it up. We are a team of IT experts and other professionals working for our clients around the world (including Israel, Austria, USA). We go far beyond the HR category. We build IT teams and also help manage them. 👉 10 years of experience 👉 +100 clients worldwide +300 hires per year 💎 We have won the prestigious "Forbes Diamonds" award four times (2022, 2023, 2024, 2025). We are a member of the European Fast Growth Icons network and FinTech Poland. We are ranked 18th among the 100 fastest growing companies 2023 by Clutch. DO YOU HAVE ANY QUESTIONS? Contact the recruiter responsible for this process directly. Aleksandra Mazur Senior IT Research Consultant aleksandra.mazur@speedapp.pl +48 728 360 029

🏢 Summary: B2B role to design and build high-scale infrastructure and platform solutions in .NET 8 for a global travel-tech product used by millions of users. The position focuses on developing a new architecture and delivering end-to-end solutions for internet-scale systems in a fast-paced environment. 🗂️ Requirements: 5+ years of commercial experience with .NET Core and C#, Strong foundation in computer science, Proficiency in object-oriented design, Knowledge of design patterns, Knowledge of algorithms and data structures, Experience designing end-to-end internet-scale solutions, Experience with large-scale production environments, Good understanding of SQL Server, Good understanding of Redis, Fluent English (written and verbal) 📃 Skills: .NET, C#, SQL, SQLServer, Redis, OOP, DesignPatterns, Algorithms, DataStructures 🏢 Description: Join the client's team in the travel-tech industry. RESPONSIBILITIES In this role, the infrastructure and platform used daily by millions of travelers worldwide will be designed and built. The focus is on full transparency, continuous improvement, innovation, and maximizing the use of technology. The team will be responsible for designing and developing a new architecture in .NET 8 to support high-scale products. REQUIREMENTS A solid foundation in computer science and strong competencies in object-orienteddesign, design patterns, algorithms, and data structures, with solid developmentexperience in .NET Core / C# - At least 5+ years experience. Thrive in a fast-paced environment, able to adapt and learn new technologies quickly. Hands-on experience designing, developing, and deploying end-to-end solutions for internet-scale problems. Good understanding of SQL Server and Redis. Experience with large-scale production environments. Excellent communication skills, initiative, and teamwork. High level of communication skills (written and verbal) in English NICE TO HAVE Experience in travel tech. Working with CI/CD is an advantage. Experience with containers and Kubernetes. Experience with NoSQL databases (like Elasticsearch) WHAT DO WE OFFER ON THIS PROJECT? Cooperation based on a B2B contract. Hybrid work from Warsaw (2 times a week in the office). The support of a dedicated mentor. In the relationship, we focus on direct communication. When you join speedapp, you will be put in touch with a dedicated mentor who will make sure that you enjoy working with us and with the client. Events and integration meetings, as well as participation in various initiatives, e.g., sports. Access to the benefits offering (medical care, life insurance, Multisport card). WHAT DOES THE RECRUITMENT PROCESS LOOK LIKE? Application: Apply and submit your CV. After the application review, the recruiter will contact selected candidates by phone. Screening: Have a conversation with a speedapp recruiter about your experience. Next steps: The speedapp recruiter will explain the recruitment process for the specific position. The speedapp recruiter will stay in touch with you throughout the entire process. ABOUT SPEEDAPP At speedapp, we believe that an organization is only as good as the people who make it up. We are a team of IT experts and other professionals working for our clients around the world (including Israel, Austria, USA). We go far beyond the HR category. We build IT teams and also help manage them. 👉 10 years of experience 👉 +100 clients worldwide +300 hires per year 💎 We have won the prestigious "Forbes Diamonds" award four times (2022, 2023, 2024, 2025). We are a member of the European Fast Growth Icons network and FinTech Poland. We are ranked 18th among the 100 fastest growing companies 2023 by Clutch. DO YOU HAVE ANY QUESTIONS? Contact the recruiter responsible for this process directly. Aleksandra Mazur Senior IT Research Consultant aleksandra.mazur@speedapp.pl +48 728 360 029