Fullstack Engineer - Intelligent Agents & Systems

As a Fullstack Engineer, you will be a core contributor to Zyphra’s Agentic Systems and Interaction projects. You will be at the forefront of building a next-generation desktop and browser-based agent (end-to-end) that can autonomously navigate the web, interact with filesystems, and complete complex user tasks. This role spans frontend interfaces, secure sandboxing environments, large-scale document search and retrieval, and language/vision model integration. We encourage all candidates to apply, even if they don't gather all the requirements.

• Design and implementation of different agentic system designs capable of interacting with browsers, operating systems, enterprise filesystems, collaboration tools ,among others

• Building search and retrieval pipelines across large-scale structured and unstructured data

• Build the backend layer for RAG systems and other information context management systems required for agents to operate

• Integrating LLMs, vision models, reinforcement learning, and scaffolding frameworks for autonomous, multi-step decision-making

• Engineering secure virtualized runtimes and backend services for agent execution

• What matters most is your drive to build production-grade software

• We value velocity and curiosity, especially in fast-moving and ambiguous environments

• Proficiency in Python and a deep understanding of building and debugging complex end-to-end applications

• Experience working with SaaS environment and production workloads, web interfaces, databases, search engines, and queuing systems

• Experience developing browser extensions or automation tools with fine-grained control over the browser (mouse, tabs, DOM)

• Understanding of LLMs, prompting techniques, and orchestration frameworks for multi-step reasoning

• Ability to work across the whole stack from web interfaces to control plane and data infrastructure like queuing systems, databases, and search indexes.

• Experience designing or working with secure and virtualized execution environments

• Excellent communication and collaboration skills across product, research, and engineering teams

• Experience building or integrating retrieval-augmented generation (RAG) systems

• Experience working with enterprise security and compliance frameworks (e.g., SOC 2)

• Familiarity with vector databases and large-scale document indexing

• Knowledge of web automation tools and headless browser environments (e.g, Puppeteer, Playwright)

• Understanding of sandboxed or containerized compute environments with strict access controls

• Comfort designing user-facing agentic workflows and reasoning systems that span multiple modalities (text, vision, actions)

• Experience using and fine-tuning models for screen reading, OCR, or UI understanding

• Background in HCI or interest in building intuitive agent interfaces that extend human capabilities

• Machine Learning experience as a double bonus

• Our research methodology is grounded in methodical, step-by-step approaches to ambitious goals. Both deep research and engineering excellence are equally valued

• We strongly value new and crazy ideas and are very willing to bet big on new ideas

• We move as quickly as we can; we aim to minimize the bar to impact as low as possible

• We all enjoy what we do and love discussing AI

• Comprehensive medical, dental, vision, and FSA plans

• Competitive compensation and 401(k)

• Relocation and immigration support on a case-by-case basis

• On-site meals prepared by a dedicated culinary team; Thursday Happy Hours

• In-person team in San Francisco, California with a collaborative, high-energy environment