Principal Software Development Engineer, Sonos

• Bachelor’s Degree in Computer Science, Software Engineering, or equivalent experience
• 8+ years of experience in embedded or systems-level software engineering
• Strong proficiency in C++
• Experience working with REST and/or WebSocket-based APIs
• Experience debugging complex, multi-threaded systems
• Experience working with telemetry, instrumentation, or performance measurement frameworks
• Deep understanding of networking fundamentals (TLS/mTLS, WebSocket, HTTP, LAN communication)
• This role requires commuting distance to our main engineering office in Seattle or Boston
• If you love solving deep technical challenges, analyzing real-world data, and delivering meaningful improvements to millions of listeners, we want to talk with you
• Research shows that candidates from underrepresented backgrounds often don’t apply for roles if they don’t meet all the criteria. We encourage you to apply even if you don’t meet every requirement

Desirable

• As a Principal Embedded Software Engineer on the Player API & Control team, you will lead performance-critical and customer-facing initiatives across the Sonos player stack
• You will have a direct impact on the responsiveness, scalability, and reliability of core playback and control experiences
• This role sits at the intersection of embedded systems, distributed communication protocols, telemetry, and cross-platform API design
• You will work across teams including App, Cloud, Security, Data, and QA to identify performance bottlenecks, design architectural improvements, and ensure measurable customer impact
• Lead performance and reliability initiatives across the Sonos APIs
• This engineer will work on Player Control components and participate in developing software for enabling new products
• Collaborate across teams to mentor local junior peers and facilitate internal development and testing
• Participate in all aspects of the software development life cycle including planning, requirements, development, and testing
• Act as a customer advocate by participating in the product definition and planning process
• Support service initiatives that adhere to best practices for security, scalability, cost, and overall performance
• Identify and eliminate latency bottlenecks in player-to-app and player-to-cloud communication
• Design and implement architectural improvements (e.g., async command execution, protocol optimizations, reduced handshake overhead)
• Use telemetry and customer data to correlate code changes to real-world impact
• Partner cross-functionally with App, UX, PM, and Data teams to improve end-to-end user experience
• Mentor engineers through design reviews, code reviews, architecture discussions, and root cause investigations
• Proactively investigate system-level issues before they escalate into customer-impacting problems
• Present performance findings and architectural proposals to engineering leadership and broader forums
• Impact of This Role:
• This role will directly influence:
• Playback latency and responsiveness
• Player Control components
• Command execution performance across devices
• Customer-reported reliability metrics
• Cross-team API usability and scalability
• The long-term architecture of the Player API platform
• This is a senior-level IC5 role expected to operate with autonomy, technical depth, and cross-team influence