Top Principal Software Engineer Jobs in San Francisco, CA

Lead architecture and technical strategy across an infrastructure platform ecosystem. Drive hands-on architectural improvements to graph engine and backend services, reduce technical debt, establish standards, champion AI-first engineering practices, run architecture/code reviews and mentorship, and collaborate with product and leadership to ensure scalable, extensible systems.

Architect and build AI-native production systems across a multi-language stack, design offline and online evaluation frameworks for LLMs, monitor live model behavior and drift, lead architecture reviews, mentor senior engineers, and prototype and ship AI capabilities while ensuring reliability and correctness in a regulated domain.

Lead design, development, and support of enterprise infrastructure and services. Drive architecture discussions, prototypes, capacity planning, and system launches. Troubleshoot performance, collaborate across teams and open-source communities, document solutions, and support on-call rotations to ensure reliable, scalable cloud and Linux-based systems.

Design and deliver large-scale, cloud-native and AI-enabled Kubernetes/AKS solutions. Implement, optimize, and maintain Kubernetes components and container orchestration across Azure, on-prem, and edge. Integrate AI capabilities, participate in on-call rotations, mentor engineers, and collaborate cross-functionally to improve reliability, observability, performance, and operational consistency at scale.

Design, implement, and operate production-quality AI framework components, benchmark and optimize large model training and inference across GPUs and Microsoft hardware, build automation and observability, drive cross-team projects from definition to deployment, and provide technical leadership and mentorship for improvements in performance, reliability, and model onboarding velocity.

Lead design and implementation of low-latency, multi-modal neuroscience research systems: instrument control, data acquisition, high-throughput pipelines, experiment UIs, and cloud infrastructure. Define technical roadmap, mentor engineers, and ensure production reliability and performance for large-scale neural data workflows.

Lead architecture, integration, installation, upgrade, and enterprise implementation of Privileged Access Management tools (CyberArk, Entra, BeyondTrust). Design and code complex software solutions, align business strategy with technology, provide technical guidance, and lead problem-solving and documentation for PAM initiatives.

Lead design and implementation of Azure full‑stack, scalable skilling platform features. Drive CI/CD, reliability, automation, and AI/LLM-enabled capabilities. Mentor engineers, enforce engineering best practices, coordinate cross-team dependencies, and improve test automation and observability for enterprise-scale services.

Lead architecture, development, and maintenance of high-performance cross-platform desktop and mobile audio applications using C#/.NET. Design low-latency streaming, metadata and networking systems, drive cross-platform initiatives, mentor engineers, implement CI/CD and AI-assisted workflows, and improve performance, scalability, and reliability.

The Principal Software Engineer - Backend drives technology direction for backend systems, ensures service reliability, and mentors teams while shaping architecture and standards across Autodesk's systems.

Lead hardware strategy, performance architecture, and benchmarking for large-scale Microsoft 365 and AI workloads. Investigate performance, scalability, and efficiency across compute, GPU, memory, storage, networking, and accelerators. Partner with Azure and platform teams, build AI-assisted performance engineering tools, and influence cross-organizational architecture and infrastructure decisions.

Design and deliver large-scale, resilient AI and Kubernetes infrastructure for hybrid environments. Implement, optimize, and maintain cloud-native, container orchestration solutions; integrate AI capabilities; participate in on-call rotations; mentor engineers and drive reliability, observability, and performance at scale.

Design, implement, and maintain high-quality, highly available microservices for Azure Messaging and Fabric. Drive AI adoption to improve development practices, optimize system IO and performance, and lead innovation in product and engineering processes while following rigorous development and security screening practices.

Lead architecture and roadmap for Azure PostgreSQL systems; design and review scalable, maintainable database engine features (query processing, storage, transaction logging, recovery, versioning, IO, scale-out). Influence coding standards and run code reviews, write proof-of-concept or production code, contribute to open-source PostgreSQL/Linux, and participate in rotational on-call operations.

Work on end-to-end AI performance for LLMs: benchmark and optimize inference on GPUs and Microsoft silicon, build tooling for performance insights and model porting, implement and test components in AI/DNN frameworks, and collaborate with internal and external partners to reduce hardware footprint and accelerate deployments.

The Senior Principal Product Architect leads the architecture of Workload Automation and DevOps solutions, focusing on automation technologies, hybrid cloud environments, and mentoring teams to modernize software engineering processes.

Lead the technical roadmap and design for Marqeta's core issuing and processing platform. Drive high-impact initiatives to improve performance, reliability, scalability, and cost-efficiency. Write, review, and optimize code across the stack, partner with product, mentor technical leads, and evangelize best practices for resiliency, security, and multi-region systems.

Lead design and implementation of core data systems for a scalable healthcare automation platform. Architect durable data models, manage workflow state and historical data, ensure traceability, observability, and data integrity. Drive schema management, testing, and reliability improvements while collaborating with engineering teams to reduce operational overhead and support growth.

The Principal Software Engineer at Snout will define architectural direction, build features across the stack, and enhance team effectiveness, ensuring quality and performance.

As a Principal Software Engineer, you will lead AI networking system transformations, manage complex customer engagements, and influence NVIDIA's networking technologies.

Lead backend and full-stack engineering strategy, design and deliver scalable, secure distributed systems and microservices for government customers. Drive architecture, data design, observability, CI/CD, cloud-native patterns, mentoring, and large modernization initiatives while collaborating with product and stakeholders.

Lead full‑stack development and ownership of ZoomInfo's Mesh AI platform: build React frontends, backend APIs, cloud infrastructure, LLM integrations, orchestration workflows, developer SDKs, respond to incidents, ensure quality, and mentor engineers.

Define next-generation graphics and compute capabilities for Direct3D and HLSL. Collaborate with GPU vendors and industry groups, influence standards, design and ship new features, and analyze and optimize workloads across modern GPU architectures.

Lead technical strategy and hands-on development of HubSpot's build, test, and deploy platform. Design scalable CI/CD, test orchestration, and AI-powered QA agents, drive architectural decisions, remove pipeline bottlenecks, and deliver cross-team initiatives that increase deployment velocity and reliability for thousands of engineers.

Technical leader on the Elasticsearch Search team driving design and implementation of search and vector features, improving relevance, contributing to Lucene, mentoring engineers, triaging community issues, and writing idiomatic modern Java for a distributed, collaborative team.