Software Engineer -.NET Libraries

Do you want to help shape the future of .NET, one of the world's most widely used open-source developer platforms? We are looking for a passionate Software Engineer to design and build modern, high-performance libraries that power millions of applications across desktop, mobile, cloud, and IoT environments.

In this role, you will contribute to .NET libraries and the broader .NET. You will help design and implement new features, improve existing components, and enhance core platform capabilities across areas such as the Base Class Library (BCL), data access frameworks, and web application frameworks.

You will work on challenging engineering problems involving performance, scalability, reliability, APIs, and developer experience. This includes designing clean, maintainable architectures, improving efficiency, and building solutions that developers worldwide rely on every day.

We embrace modern engineering practices, including AI-assisted development workflows. You will leverage AI tools and technologies to accelerate development, improve code quality, assist with code generation and refactoring, enhance debugging and testing, automate repetitive tasks, and support faster experimentation and problem solving. We value engineers who can effectively combine strong software engineering fundamentals with emerging AI capabilities to deliver better outcomes.

As part of our open development culture, you will collaborate with engineers and the global developer community through GitHub, contributing to discussions, design proposals, code reviews, and open-source initiatives. You'll have the opportunity to influence the direction of a platform used by millions of developers around the world.

Responsibilities

• Design, develop, and maintain the .NET Core libraries across multiple areas and platforms
• Implement new library features and evolve existing APIs to improve performance, usability, and developer productivity
• Leverage AI-assisted development tools and practices to improve engineering productivity and accelerate implementation
• Investigate, diagnose, and resolve complex issues across Windows, Linux, macOS, iOS, and Android
• Optimize libraries for a wide variety of workloads including mobile, desktop, and cloud-native applications
• Collaborate with other engineering teams and participate in open-source development on GitHub
• Contribute to design discussions, code reviews, and architectural decisions for the platform

• Bachelor's or Master's degree in computer science or a related field, or equivalent work experience.
• Solid programming skills in one or more of the following languages: C#, Java, C++, or Python.
• Passion for developer experience and an eagerness to understand what makes great tools.
• Excellent written and verbal communication skills with the ability to collaborate across diverse, distributed teams.

This position will be open for a minimum of 5 days, with applications accepted on an ongoing basis until the position is filled.

Microsoft is a global technology company headquartered in Redmond, Washington. Our mission is to empower every person and every organization on the planet to achieve more. We develop, license, and support a wide range of software products, services, and devices that help individuals and businesses realize their full potential.

Our flagship products include the Microsoft 365 productivity cloud, Windows operating system, Azure cloud platform, and Dynamics 365 business applications. We are also a leader in areas such as artificial intelligence, cybersecurity, developer tools, and gaming through Xbox and Game Pass.

With operations in more than 190 countries and over 220,000 employees worldwide, Microsoft is committed to responsible innovation, inclusive economic growth, and sustainability. We work closely with governments, industries, and communities to ensure that technology serves the public good and helps address some of the world’s most pressing challenges.

As we celebrate our 50th anniversary in 2025, we continue to look forward—investing in AI, cloud, and quantum computing to shape the future of work, education, and society at large scale.