Senior .NET Developer

🏢 Summary: Development of backend services and back-office applications for a modern TV streaming platform, integrating with BSS, IAM, and third-party streaming services. The role focuses on building scalable, high-load distributed systems using .NET and cloud technologies while ensuring operational stability and continuous improvement. Work is carried out in Agile teams with strong emphasis on architecture and best practices. 🗂️ Requirements: Strong experience with .NET and C#, Professional experience with Python, Understanding of OOD, SOA, SOLID principles, Experience with SQL and NoSQL databases, Experience with RESTful APIs, Experience with distributed, large-scale, high-load systems, Hands-on experience with AWS, Hands-on experience with Kubernetes, Experience with ELK stack, Experience with CI/CD pipelines, Experience with Git 📃 Skills: .NET, C#, Python, SQL, NoSQL, REST, AWS, Kubernetes, ELK, CI/CD, Git, OOD, SOA, SOLID 🏢 Description: Your responsibilities: Develop and enhance backend services supporting a modern TV streaming platform, Build and maintain back-office applications integrating with: BSS (Business Support Systems), IAM (Identity and Access Management), 3rd party streaming services, Collaborate with product owners and cross-functional teams to shape user-centric solutions, Apply software architecture principles and design patterns to create scalable, maintainable, and testable systems, Ensure operational stability through monitoring, maintenance, and platform upgrades, Contribute to continuous improvement of development practices and technology choices, Work in Agile teams and participate in cross-functional initiatives. We are looking for you, if you have: Strong experience with .NET / C# as a primary development environment, Professional experience with Python, Solid understanding of: OOD, SOA, SOLID principles, Experience working with: SQL and NoSQL databases, RESTful APIs, Experience designing and maintaining distributed, large-scale, high-load systems, Hands-on experience with cloud platforms (AWS), Kubernetes , and ELK stack, Familiarity with CI/CD pipelines and GIT. Nice to have: Experience with application monitoring tools (e.g. Datadog ) Knowledge of Go , Node.js , or PHP Experience with GraphQL Background in TV, media, or streaming platforms We offer: Participation in interesting and demanding projects Flexible working hours A great, non-corporate atmosphere Stable employment conditions (contract of employment or B2B contract) Opportunities for development and promotion Attractive package of benefits Work model: remote or hybrid (2 days per week from the office) We reserve the right to contact the selected candidates.

🏢 Summary: The offer is for a Back End Developer responsible for building and maintaining APIs, backend services, and scalable system architecture within the .NET ecosystem. The role focuses on designing microservices-based solutions, integrating databases and third-party services, and ensuring high performance, security, and reliability. It includes remote work options under a B2B contract. 🗂️ Requirements: Strong knowledge of backend technologies, especially .NET ecosystem, Experience with .NET 8+ and ASP.NET Core, Experience with relational databases (PostgreSQL or MySQL), Experience with NoSQL databases (MongoDB), Experience building RESTful APIs using Swagger / OpenAPI, Experience with Microservices Architecture, Experience with RabbitMQ for message queuing, Experience with Docker and Kubernetes, Experience with Auth0 and JWT-based authentication, Experience with cloud services (AWS, Azure or GCP) 📃 Skills: .NET, ASP.NET, C#, PostgreSQL, MySQL, MongoDB, REST, Swagger, OpenAPI, Microservices, RabbitMQ, Docker, Kubernetes, Auth0, JWT, AWS, Azure, GCP 🏢 Description: Description The Back End Developer will develop and maintain APIs, services, and server-side logic and databases. You'll contribute to system architecture and help scale our platforms. You will ensure high performance and responsiveness of applications, working alongside frontend developers and other team members. Responsibilities Design, build and implement backend services and APIs Design data models and manage database integration Integrate with databases and third-party APIs Implement security and data protection measures Optimize performance and security of systems Requirements Strong knowledge of backend technologies / languages, particularly .NET ecosystem Experience in .NET 8+ (or latest version), including ASP.NET Core for building web APIs and services. Experience with relational databases, such as PostgreSQL, MySQL for structured data, complex queries, and ACID compliant operations Experience with NoSQL databases, such as MongoDB, for handling unstructured or semi-structured data, schema flexibility, and high-throughput scenarios Experience with RESTful APIs for development of robust, secure RESTful services with best practice for APU design, versioning and documentation, using Swagger / Open API Experience in Microservices Architecture, for design, implementation, and management of distributed systems using microservices principles, ensuring loose coupling, scalability, and resilience Experience in Message Queuing:, using RabbitMQ for asynchronous communication, event-driven architecture, and reliable message brokering between services Experience in Containerization and Orchestration, using Kubernetes (K8s) for deploying, scaling, and managing containerized applications in production environments and Docker for containerization Experience in Authentication, using Auth0 for identity management, JWT-based authentication Experience in Cloud Services, such as AQS, Azure, GC Nice to have Experience in Rabbit MQ Middleware Prior experience in the EdTech domain (e-learning platforms, digital classrooms, LMS) Knowledge of learning science, instructional design, or accessibility standards (e.g., WCAG) Familiarity with tools like Moodle, Canvas, Zoom SDK, or Google Classroom integration Working conditions Partly / fully remote B2B contract

🏢 Summary: Backend Developer role focused on designing and building scalable, cloud-based applications using Java and Spring Boot in a microservices architecture. The position involves developing and deploying distributed, event-driven services on Azure using modern containerization and API technologies. The offer emphasizes building reliable, high-quality backend systems with up-to-date cloud-native practices. 🗂️ Requirements: Strong Java development experience, Experience with Spring Boot, Experience with microservices architecture, Experience with cloud-native applications, Familiarity with Azure, Knowledge of Kafka or similar messaging systems, Understanding of GraphQL or REST APIs, Experience with Docker, Experience with Kubernetes 📃 Skills: Java, Spring, SpringBoot, Microservices, Azure, Kafka, GraphQL, REST, Docker, Kubernetes 🏢 Description: We are seeking a talented Backend Developer to join our team, contributing to the design and development of modern, cloud-based applications. The role focuses on building scalable and maintainable services using up-to-date technologies and best practices. Key Responsibilities: Develop and maintain backend services using Java and Spring Boot . Build and support microservices solutions for distributed systems. Work with cloud platforms such as Azure , including event-driven architectures. Implement and consume APIs using GraphQL or REST. Package and deploy applications using Docker and Kubernetes . Collaborate with team members to deliver reliable, high-quality software. Required Skills & Experience: Strong background in Java development with Spring Boot . Experience with microservices and cloud-native applications. Familiarity with Azure , Kafka , or similar messaging/event systems. Understanding of API design ( GraphQL /REST). Practical experience with containerization ( Docker , Kubernetes ). Nice to Have: Knowledge of CI/CD practices and automated deployments. Experience with monitoring, logging, or observability in distributed systems.

🏢 Summary: Full-Stack / Backend Developer role focused on building and maintaining scalable applications and REST APIs that support client products. The position involves developing new integrations, enhancing existing backend and frontend systems, and improving platform performance and reliability. You will contribute to architecture improvements and work within a cloud-based environment. 🗂️ Requirements: Minimum 3 years commercial experience, Experience with Java, Experience with Spring Boot, Experience with AWS, Experience with MongoDB, Experience with PostgreSQL, Experience with React.js, Experience designing REST APIs, Knowledge of backend architecture, Experience with cloud environments, Understanding of clean code principles, Experience working in Agile environment 📃 Skills: Java, SpringBoot, AWS, MongoDB, PostgreSQL, React, REST, Agile, Cloud, Architecture 🏢 Description: We are looking for an experienced Full-Stack / Backend Developer to join our team and help build scalable applications and APIs supporting our clients’ products. You will work on both backend and frontend solutions, contributing to product development, system improvements, and ongoing platform stability. Your Responsibilities Develop new APIs to support client integrations and business features. Maintain and enhance existing backend and frontend applications. Fix bugs and improve application performance and reliability. Upgrade and support operational aspects of the platform. Identify opportunities to improve product quality, architecture, and development processes. Collaborate with developers, product teams, and stakeholders to deliver high-quality solutions. Participate in code reviews and contribute to best engineering practices. Required Skills Minimum 3 years of commercial experience with: Java Spring Boot AWS MongoDB PostgreSQL React.js Experience designing and developing REST APIs. Knowledge of backend architecture and modern web applications. Experience working with cloud-based environments (AWS). Understanding of software development best practices and clean code principles. Ability to work in an Agile development environment.

🏢 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: 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: Backend Software Engineer role focused on building, testing, and maintaining C#/.NET-based backend systems and microservices. The position involves designing system architecture, developing REST/GraphQL APIs, and ensuring reliable CI/CD-driven deployments. You will work on scalable systems used across multiple European markets. 🗂️ Requirements: 5+ years of commercial experience in C# development, Strong experience with .NET Core and .NET Framework, Solid knowledge of data structures and algorithms, Strong understanding of software engineering principles and testing, Experience with PostgreSQL, MSSQL, or DynamoDB, Experience designing and implementing REST or GraphQL APIs, Hands-on experience with CI/CD processes, Knowledge of OOP, SOLID principles, and Clean Code, Experience designing software architecture for distributed systems 📃 Skills: C#, .NETCore, .NETFramework, TypeScript, REST, GraphQL, PostgreSQL, MSSQL, DynamoDB, CICD 🏢 Description: About the role You will need to be proficient in C# backend development with a thorough understanding of the .NET technologies involved. Strong backend skills where you can demonstrate your ability to apply these technologies, as well as deploy and maintain them will be crucial to success. Technologies we work with: C#, .NET Core, .NET Framework, TypeScript, JavaScript, Python, Node.js, REST/GraphQL APIs, React, AWS, Terraform Responsibilities Designing, writing, testing functionalities for a backend system written in C# Design software architecture between backend, frontend and mobile apps Deploying and maintaining microservices in AWS using Terraform Debugging and maintaining system on production used by consumers from several European countries Scoping and assessing the complexity of features Participating in sprint planning, daily sprints and meetings with product owners for grooming new features Collaborating with other team members and teams who depend on functionalities that you develop Recruiting and mentoring new team members Required qualifications 5+ years of production software development experience in C# engineer role Solid hands-on experience in .NET Core and .NET Framework technologies Experience in working with AWS and Terraform / CloudFormation Strong knowledge of DBMS like MS SQL / PostgreSQL / DynamoDB Expertise of REST APIs Strong hands-on experience of CI&CD processes Proficiency in OO design patterns, SOLID principles, Clean Code and solving architectural problems Computer Science degree AI Tooling usage Able to work with Agile methodologies such as SCRUM and/or Kanban Good communication and collaboration skills Self-motivation, proactive attitude Proficiency in English Nice to have Experience in developing Cloud and Infrastructure solutions with AWS and CI/CD processes supported by tools like Docker, Kubernetes, Jenkins, Terraform, CircleCI, GitlabCI, Datadog, etc. Exposure to frontend development in React Working experience with one of the object-oriented and/or functional languages such as Java, TypeScript, Elixir, C++, Golang, Erlang, Python, Kotlin

🏢 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: Backend Developer role focused on modernizing and transforming legacy sales systems using Node.js and .NET technologies. The position involves building and maintaining APIs, databases, and event-driven architectures within AWS, while supporting deployment and continuous improvement processes. The role emphasizes proactive development, high-quality testable code, and collaboration on large-scale backend initiatives. 🗂️ Requirements: 5-6 years experience with Node.js, 2-3 years experience with .NET, Strong proficiency in TypeScript and JavaScript, Experience building and maintaining APIs, Experience with PostgreSQL and DynamoDB, Experience with event-driven architecture, Experience with AWS services, Ability to write modern, testable, high-quality code, Experience with CI/CD pipelines, Experience maintaining and modernizing legacy systems 📃 Skills: Node.js, TypeScript, JavaScript, .NET, AWS, Lambda, DynamoDB, PostgreSQL, RDS, ECS, Kafka, EventBridge, CDK, GitLab, CI, Docker, Localstack 🏢 Description: We're seeking an experienced & energetic Backend Developer specializing in TypeScript/JavaScript/.NET to enhance the global Sales ecosystem. This role focuses on transforming backend systems, emphasizing proactive development and team empowerment. Candidates should bring a blend of Node.js and .NET expertise to the table, along with a collaborative spirit and a commitment to writing modern, testable code. Our Client’s team, comprising about 25 individuals, is modernizing legacy systems to fulfill local market needs while improving our processes continually. If you're motivated by challenges and have a passion for creating high-value solutions, we want to hear from you! Main Responsibilities: Drive initiatives and collaborate with team members on larger projects. Fix bugs and implement smaller enhancements across the application. Participate in creating and maintaining APIs using AWS services. Develop and improve databases with a focus on PostgreSQL and DynamoDB. Contribute to an event-driven architecture utilizing Kafka and AWS EventBridge. Manage deployment processes using AWS CDK and GitLab CI. Support legacy system maintenance and modernization. Key Requirements: At least 5-6 years of experience as a Node.js Developer. 2-3 years of experience with .NET. Energetic and inspiring personality who thrives on challenges. Hands-on work ethic in collaboration with team members. Proficiency in writing modern, testable, and high-quality code. Natural inclination towards evolutive maintenance. Nice to Have: AWS experience (Serverless Lambda, DynamoDB, RDS, ECS, AWS CDK). Knowledge of Localstack. Experience with Docker. Other Details: This position allows for team activities at least twice per year in Sweden, with a focus on modernizing our legacy systems into proactive, quality-focused solutions. Join a team of about 25 members dedicated to driving transformative change in our sales ecosystem.

🏢 Summary: Senior Full-Stack Engineer (.NET & React) role focused on building scalable APIs and microservices powering music and content experiences across a global fitness platform. The position involves designing distributed backend systems, supporting real-time music playback, and collaborating cross-functionally to deliver high-quality features at scale. Hybrid work model in Warsaw with competitive salary and comprehensive benefits. 🗂️ Requirements: 5+ years of professional software development experience, Strong knowledge of C#, Strong knowledge of .NET ecosystem, Experience building and maintaining RESTful APIs, Understanding of asynchronous programming, Understanding of multithreading, Experience with NoSQL databases, Familiarity with microservices architecture, Working knowledge of React, Vue.js or similar frontend frameworks, Experience with CI/CD pipelines, Experience with automated testing, Understanding of DevOps principles, Understanding of Agile methodologies, English communication skills 📃 Skills: C#, .NET, REST, React, Vue, MongoDB, AWS, S3, SQS, Lambda, Microservices, CI/CD, Docker, Kubernetes, RabbitMQ, NServiceBus 🏢 Description: We are hiring on behalf of our client, a global innovator in fitness and wellness technology. Their mission is to empower people to live fit, strong, long, and happy lives by delivering integrated experiences to millions of members anytime, anywhere. We are looking for a Senior Full-Stack Engineer (.NET & React) to join the Content Platform team, focused on building systems that power music-related experiences across the product ecosystem. In this role, you will design and develop APIs and backend services that support everything from instructor class planning to real-time music playback during workouts. This is a hands-on engineering role with strong ownership, where you will work on distributed systems, collaborate across teams, and directly impact user-facing features at scale. Key takeaways: Stack : C#, .NET, REST APIs, React/Vue, MongoDB, AWS (S3, SQS, Lambda), microservices Salary : 23 000 PLN - 28 000 PLN gross on the Contract of Employment Working model : Hybrid - 3 days/week from the office Location : ul. Grzybowska 60, Warsaw Recruitment process : A call with MOTIFE Recruiter Panel interviews with the team (coding, architecture, and cross-collaboration interviews, Hiring Manager meeting) Responsibilities: Backend Development & Architecture Design, build, and maintain scalable APIs and microservices supporting content and music-related features Develop systems for managing music catalogs, class planning tools, and platform integrations Ensure high performance, reliability, and scalability of backend services Technical Excellence Write clean, maintainable, and well-tested code with a focus on long-term sustainability Drive best engineering practices, including CI/CD, automated testing, logging, and monitoring Continuously improve system architecture while avoiding unnecessary complexity Collaboration & Delivery Partner closely with Product, Design, and QA to deliver high-quality features Actively participate in architecture discussions, code reviews, and technical planning Translate UI/UX requirements into reliable backend solutions Engineering Culture Contribute to a culture of code quality, ownership, and continuous improvement Promote practices such as refactoring, pair programming, and iterative development Support knowledge sharing and help evolve engineering standards across the team Requirements: Technical Expertise 5+ years of professional software development experience Strong knowledge of C# and .NET ecosystem Experience building and maintaining RESTful APIs Solid understanding of asynchronous programming and multi-threading Experience with NoSQL databases (e.g., MongoDB) Familiarity with microservices architecture Frontend & Platform Awareness Working knowledge of React, Vue.js, or similar frontend frameworks Understanding of system integration and API-driven development Engineering Practices Experience with CI/CD pipelines, automated testing, and DevOps principles Understanding of Agile and Lean development methodologies Strong focus on code quality, maintainability, and scalability Collaboration & Mindset Strong communication skills in English Ability to work effectively in cross-functional teams Comfortable working in fast-paced, evolving environments Nice to Have Experience with Docker and Kubernetes Familiarity with AWS services (S3, SQS, Lambda) Experience with messaging systems (e.g., NServiceBus, RabbitMQ) What we offer: 100% paid medical care Multisport Creative tax (KUP) Home office allowance MacBook Pro