Senior .NET Developer

Connect Digital is a technology consulting company dedicated to delivering robust and innovative IT solutions for organizations operating in complex and business-critical environments. We collaborate with national and international clients, supporting their digital transformation through modern technologies, agile methodologies, and enterprise solutions. We are currently looking for an experienced Senior .NET Developer to join one of our international technology projects in Portugal. This is a 100% remote opportunity within Portugal, ideal for professionals with solid experience in C# and the .NET ecosystem, particularly those who enjoy backend development, working with business-critical systems, solving complex technical challenges, and contributing to reliable and high-performance software solutions. Key Responsibilities Design, develop, maintain, and evolve commercial applications using C# and .NET technologies.Develop and integrate Web Services, Web APIs, and service-oriented solutions.Contribute to applications built around N-Tier and Service-Oriented Architecture (SOA) principles.Apply strong Object-Oriented Programming (OOP) principles, software design patterns, and engineering best practices.Work with existing and evolving .NET applications, contributing to both new development and the modernization of established systems.Design and optimize database structures, queries, and data-access components, with particular focus on SQL and MySQL.Identify and resolve application performance bottlenecks, improving the efficiency, scalability, and reliability of systems.Develop and maintain unit, integration, and functional tests to ensure the quality and stability of delivered solutions.Troubleshoot complex technical and production issues, identifying root causes and implementing reliable solutions.Participate in code reviews and contribute to high standards of code quality, maintainability, and software design.Use Git as part of the development and source-control workflow.Work collaboratively within an Agile/Kanban environment, participating actively in the team's development and delivery processes.Collaborate daily with an international team, discussing technical requirements, solutions, and delivery in English.Participate in releases and, when required, provide out-of-hours/on-call support for business-critical applications. Required Skills & Experience Degree in Computer Science, Software Engineering, Information Systems, or a comparable technical area.Solid professional experience developing commercial applications with C# and .NET.Strong understanding of Object-Oriented Programming (OOP) concepts and principles.Good knowledge of software design patterns and engineering principles.Demonstrable experience developing and integrating Web Services and Web APIs.Experience or good knowledge of WCF.Experience working with N-Tier architectures and/or Service-Oriented Architecture (SOA).Solid database experience, including SQL, schema design, and query development, ideally with MySQL.Experience identifying and implementing performance optimisations in applications and database interactions.Good experience with unit and functional testing; strict TDD experience is not required.Strong working knowledge of Git for source control.Experience working within Agile and/or Kanban environments.Strong troubleshooting, analytical, and problem-solving capabilities.Attention to detail and a strong focus on delivering thoroughly tested, reliable solutions.Ability to work effectively as part of a collaborative and distributed engineering team.Fluent English, both written and spoken, as there will be daily communication with an international team.Availability to participate in releases and occasional out-of-hours/on-call activities, when required. Nice to Have Experience working with legacy .NET applications and their evolution or modernization.Experience with WinForms and/or WPF.Knowledge of software and application architecture.Experience with NoSQL databases.Exposure to AWS, Azure, or GCP.Cloud certification in AWS, Azure, or GCP. What We Offer Gross annual salary between €33,000 and €35,000, depending on experience and seniority.100% remote work within Portugal.Employment contract.Meal allowance.Flexible benefits package.Health insurance.Extra day off on your birthday.One additional day off on either 24 December or 31 December. Let’s Connect If this particular opportunity is not fully aligned with your experience or career goals, we would still be happy to hear from you. At Connect Digital, we have this and other remote opportunities across different technology areas. Feel free to reach out to me directly via LinkedIn, and together we can explore other projects that may be a better fit for your profile and expectations — whether within our internal teams, product development area, or IT consulting projects. If you're interested in this opportunity or would simply like to explore what we may have available for you, feel free to send your CV to eunice.teixeira@connectdigital.global or contact me directly on LinkedIn.