Top Tech Jobs & Startup Jobs in San Francisco Bay Area, CA

Build, maintain, and improve algorithms and infrastructure for finetuning and RL training (RLHF) of large language models. Improve speed, reliability, and usability of training pipelines through profiling, instrumentation, debugging GIL contention, launching test jobs, and implementing research algorithms to support production and internal model training.

Lead system-level architecture for large-scale AI compute: define specs, evaluate vendor designs, drive interconnect, power, thermal, and reliability strategies, develop validation and bring-up plans, and partner with ML, infrastructure, and supply chain teams.

Design and build real-time risk decisioning and tooling to prevent payments fraud. Implement fraud signals at scale, manage dispute and chargeback workflows, monitor metrics (loss, dispute, approval, false positives), lead investigations into emerging fraud patterns, and collaborate cross-functionally with finance, support, legal, data science, and external payment partners.

Build and maintain the shared web platform for Claude.ai: shared UI components, BFF APIs, build/deploy pipelines, and observability. Improve developer velocity, performance, reliability, and documentation to enable other product teams to ship quickly and reliably.

The Research Engineer will enhance RL training infrastructure, streamline research processes, and collaborate with teams to improve model deployment efficiency.

Build and productionize threat discovery infrastructure: ingestion pipelines, automated detection systems, YARA rule tooling, external CTI integrations, behavioral analytics, and investigator-facing tooling to scale investigations and reduce false positives.

Join the Web Product team to develop features for Claude.ai, transform user interaction, and enhance AI collaboration. Full-stack work across frontend and backend.

Lead the strategy and execution to bring Claude Tag to new collaboration surfaces. Define interaction models, own roadmap and external partnerships, drive adoption from design partners to large-scale rollouts, and collaborate closely with engineering on product and model behavior.

Lead and grow the Search Platform team building indexing, retrieval, ranking, and serving infrastructure for Claude. Own platform strategy, search quality, evaluation, and production reliability. Balance product and research demands, collaborate across product, research, and infrastructure, perform design reviews and incident follow-ups, and recruit and retain senior engineers.

Own vision, strategy, roadmap, and execution for research-driven AI products. Partner with research and engineering to productize models, identify high-potential use cases, synthesize user insights, and ship model capabilities that deliver real-world value.