Principal Software Engineer - C++

The Windows App for the web is a full Windows client implemented inside a browser runtime. It powers Azure Virtual Desktop and Windows 365 by translating operating system expectations—graphics, input, media, identity, security and device access—into something that can execute reliably inside modern web platforms, bringing a “like-local” Windows experience to millions of enterprise users.

We’re seeking a Principal Software Engineer to operate in the foundational layers of our web client, where architectural decisions directly affect performance, reliability, security posture, and long-term evolution. This role serves as a technical anchor for the client, with hands-on work spanning rendering and graphics pipelines, protocol stacks, WebAssembly-based components, media and device redirection, authentication, telemetry, and the isolation boundaries that allow a browser to behave like a high-fidelity Windows endpoint.

At this level, impact comes from working on the hardest parts of the stack while providing technical clarity through design choices and trade-offs, shaping how the system is built, integrated, and evolves as browser capabilities, cloud infrastructure, and Windows workloads continue to converge.

We’re a collaborative, high-energy group that values curiosity, craftsmanship, and a growth mindset.

What is Windows App:  https://learn.microsoft.com/en-us/windows-app/overview

Video:  https://youtu.be/j0XU59VbKOc

Why this problem space matters

This work defines how Windows runs when the browser is the platform. The solutions ship at global scale and are constrained by real-world networks, devices, and security models. For engineers who enjoy working close to the limits of what the web runtime allows—and extending it responsibly—this is a rare problem space.

What you’ll work on

You’ll operate primarily in the foundational layers of the client, where performance, correctness, and constraints are explicit:

• Rendering and interaction pipelines
  • High-performance remote graphics using Canvas, WebGL/WebGPU, and WebAssembly
  • Input fidelity across keyboard, mouse, touch, pen, and specialized devices
  • Latency control, frame pacing, bandwidth adaptation, and GPU utilization
• Client protocol and transport architecture
  • Design and evolution of remoting protocols optimized for web runtimes
  • Reliability, congestion control, and session resilience across heterogeneous networks
  • Tight coordination between browser client, gateways, and cloud services
• WebAssembly and native code integration
  • Performance-critical C/C++ components compiled to WASM
  • Memory models, threading, SIMD, and sandbox constraints
  • Deep integration with Chromium APIs and browser execution models
• Media and device redirection
  • Audio/video pipelines supporting Teams optimization and real-time collaboration
  • Multimedia redirection with strict latency and synchronization requirements
  • Device and peripheral redirection (e.g., smart cards, cameras, microphones) mapped into web-safe abstractions
• Identity, security, and isolation
  • Smart card redirection, WebAuthn/FIDO flows, and authentication pass-through
  • Clear trust boundaries between local device, browser, and remote session
  • Secure-by-design client architectures that preserve performance and usability

Microsoft’s mission is to empower every person and every organization on the planet to achieve more. As employees we come together with a growth mindset, innovate to empower others, and collaborate to realize our shared goals. Each day we build on our values of respect, integrity, and accountability to create a culture of inclusion where everyone can thrive at work and beyond.

At this level, the role is about technical ownership and direction.

You will:

• Define and drive end-to-end designs spanning browser, protocol, and cloud
• Make architectural calls under real constraints imposed by browsers and security models
• Identify performance ceilings and systematically remove them
• Partner across Windows, Chromium, Teams, and Azure to align deep technical decisions
• Raise the technical bar through design reviews, mentorship, and examples.

Required Qualifications: 

• Bach