Top C# Jobs in San Francisco Bay Area, CA

Develop scalable C++ software that defines and enforces endpoint behavior across millions of managed Windows endpoints. Responsibilities include implementing features, improving platform performance, shipping production code, designing new systems, writing architecture documents, defining subsystem contracts, and collaborating with server, UI, product, and design teams. The role requires deep Windows systems and kernel-driver expertise, with preferred experience in WHQL, minifilter or WFP drivers, macOS Endpoint Security, and Linux kernel development.

Design and develop scalable C++ software for endpoint state and control across Windows, macOS, and potentially Linux. Build reliable, multi-process systems that enforce endpoint behavior, manage local state, support IPC, and operate across millions of devices. Responsibilities include implementing features, improving platform performance, writing design documents, defining architecture and IPC contracts, and making technical decisions in an evolving, sparsely documented environment.

Develop and test systems-level C++ software that defines and enforces endpoint behavior. Initially, the engineer will own testing infrastructure and coverage for two active projects, then contribute to feature development. The role requires strong C++ fundamentals, automated testing experience, and interest in operating-system concepts such as processes, file systems, services, and APIs. Work includes learning unfamiliar systems, collaborating effectively, and supporting reliable endpoint security and management capabilities.

Design, build, and maintain Stellar Core, the distributed system powering the Stellar blockchain ledger and consensus. Develop scalable, resilient components; improve peer-to-peer networking and processing performance; investigate bottlenecks; and contribute to architecture, code reviews, RFCs, formal verification, simulations, and open-source collaboration. The role requires production C++ or Rust expertise, strong software design skills, and ownership of core subsystems.

Leads and develops a software engineering team while contributing hands-on to enterprise application design, coding, testing, code reviews, production support, and technical decisions. Builds scalable solutions using C#, ASP.NET, SQL Server, and modern web technologies; partners with product and business stakeholders; supports Agile delivery, CI/CD, troubleshooting, root cause analysis, and engineering best practices. The role also includes mentoring engineers, monitoring delivery and operational metrics, and driving continuous improvement.

Design, develop, and field high-performance Ground Control Station and C2 software using C++/Qt/QML and QGroundControl. Lead architecture and technical direction, mentor engineers, define APIs/ICDs, debug integration/latency issues, support field tests, implement post-mission debrief tools, and ensure interoperability with C2 standards.

Develop and modernize enterprise applications using C#/.NET and PostgreSQL, including refactoring a Microsoft Access/VBA application. Responsibilities include writing maintainable code, participating in code reviews, testing, documentation, deployment, and collaborating with the software development team in a fully remote environment.

Lead modernization of a 30-year-old Store Management System by reverse engineering EZC file-based platforms, migrating data and applications to PostgreSQL, and developing enterprise C/C++ software. Responsibilities include architecture, systems integration, APIs, ETL, performance optimization, troubleshooting, documentation, and maintaining business continuity. The role also applies AI-assisted development tools for code analysis, documentation, testing, and modernization while mentoring teams and supporting legacy and modern environments.

Build and validate reinforcement-learning tasks for AI agents exploring unfamiliar C repositories. Responsibilities include investigating runtime behavior, rewriting engineering questions, refining rubrics and foils, running validation workflows, documenting solutions, and addressing expert review. Work focuses on production systems such as PostgreSQL, Redis, OpenSSH, OpenSSL, and other foundational C codebases.

Leads hands-on full-stack development across architecture, implementation, testing, deployment, and support. Designs secure, scalable C#/.NET and Angular applications, cloud integrations, APIs, and data solutions on AWS. Guides developers, establishes engineering standards, manages CI/CD and automated testing, troubleshoots complex issues, and drives cloud optimization, security, and technical debt reduction. Collaborates with product, architecture, DevOps, analytics, and project teams while supporting migration of on-premises applications to AWS.

Lead a development team while remaining hands-on in full-stack engineering. Design, build, test, deploy, and support secure web applications using C#/.NET, Angular, databases, and AWS. Drive cloud migrations, architecture, CI/CD automation, application security, troubleshooting, performance and cost optimization. Mentor developers, establish engineering standards, lead technical delivery, and collaborate with product, data, DevOps, and architecture teams.

Architects, develops, and maintains high-performance C++ applications with advanced memory management and multithreaded architectures. Owns critical system components, build systems, CI/CD pipelines, containerization, debugging, profiling, and performance tuning. Leads code reviews, technical planning, and system design while mentoring engineers. Works in Linux environments with Python, shell scripting, SQL, and Git, and collaborates across teams to improve reliability, scalability, and technical growth.

Lead end-to-end development of secure, scalable web applications and data solutions supporting clinical trial operations. Design frontend and backend components using C#/.NET, Angular, AWS, and relational or non-relational databases. Guide architecture, testing, deployment, CI/CD, security, cloud optimization, and regulatory compliance. Mentor developers, oversee technical delivery, troubleshoot complex issues, and lead migration and modernization of on-premises applications to AWS.

Develop and maintain Zoox’s on-vehicle Core Data systems for capturing, storing, retrieving, and transmitting autonomous vehicle data. Responsibilities include contributing to architecture, implementing high-performance fault-tolerant systems under real-time and resource constraints, owning technical problems through rollout, and collaborating on requirements, design reviews, and code reviews.

The role involves optimizing and debugging C++ systems within a GPU cloud platform, with responsibilities including performance enhancements and customer interface improvements.

Build and optimize high-performance C/C++ and Rust server applications and feed handlers for market data. Implement parsers, petabyte-scale processing tools, and low-latency, high-throughput optimizations. Collaborate on build/deploy/CI, monitoring, and ensure reliable feature rollouts.

As a Software Engineer, you will develop and maintain the Tally software stack, enhance robot navigation and autonomy, and support CI/CD processes.

Evaluate AI coding-agent interactions for usefulness, correctness, engineering judgment, reasoning quality, and developer trust. Provide clear, opinionated feedback, distinguish response-quality levels, and help define standards for excellent interactions with tools such as OpenAI Codex, Claude Code, and Cursor. This contract role requires staff- or principal-level software engineering experience and familiarity with modern AI-assisted development workflows.

Develop and maintain the Java client library and high-performance C/C++ server applications. Implement message parsers and feed handlers, optimize for extreme throughput and low latency, build tools for petabyte-scale processing, collaborate on build/deploy/CI practices, monitor uptime, and support smooth feature rollouts.

Implement and maintain the C# client library and high-performance C++ server applications. Build message parsers and feed handlers, optimize for millions of messages/second and nanosecond latency, develop petabyte-scale data tools, collaborate on build/deploy/CI/CD, monitoring, and ensure reliable feature rollouts.

The C# / .NET Developer will design and maintain middleware applications, build Shopify integrations, and support a mobile app backend in a remote work environment.

Design and evaluate performance engineering tasks for AI training/evaluation. Optimize runtime, compilers, memory, CPU/GPU and concurrency. Produce documented solutions, evaluate AI-generated code, and build evaluation frameworks and scoring rubrics while collaborating with researchers and SMEs.

Develop user interface components for ArcGIS Pro using C# and WPF, work in an agile team, and design software solutions for raster and imagery processing.

PrivateID seeks a Principal C++ Engineer with at least 10 years of experience to lead complex systems and scale their platform in a remote-first environment.

Build and maintain scalable, cloud-native APIs using .NET. Enhance core platform components, lead architecture and testing discussions, optimize telemetry and performance, collaborate cross-functionally, conduct code reviews, and mentor team members.