Senior Software Engineer, Front End

ABOUT PIONEERING INTELLIGENCE

Pioneering Intelligence builds on Flagship Pioneering’s legacy of founding cutting-edge science and computational ventures, harnessing recent advances in AI, machine learning, and data to accelerate fundamental research and create a portfolio of AI-first companies. As part of Flagship’s integrated model of science, entrepreneurship, and capital, it transforms breakthrough ideas into world-changing companies, elevating the AI advances happening across the ecosystem in human health, sustainability, and beyond.

Position Summary

We are seeking a Senior Front End Engineer. As a key contributor in this early-stage initiative, you willarchitect and implement the user experiencefor a new platform that leverages large language models (LLMs) and AI agents to enhance complex, high-stakes workflows. This is auser-first, AI-augmented product— your work will transform abstract reasoning tasks into intuitive, high-performance tools that empower experts across diverse research domains. You will lead front-end development and collaborate closely with engineers, AI scientists, product designers, and end users. This is a rare opportunity toshape a greenfield productat the intersection of usability, flexibility, and advanced reasoning.

Key Responsibilities

• Architect, develop, and maintain high-quality, testable front-end code and workflows aligned with complex scientific and analytical use cases.
• Translate user stories, wireframes, and prototypes into production-ready features emphasizing clarity, maintainability, and reusability.
• Implement responsive, accessible, and performant UIs optimized for data-rich, interactive workflows.
• Ensure security, scalability, and observability of front-end services in cloud environments (AWS).
• Design and implement user interfaces from scratch, combining strong visual design with robust engineering.
• Create and maintain scalable, consistent, and visually appealing UI components using a modernReact.jsstack.
• Maintain front-end quality through comprehensive testing and validation of user flows and interface behavior.
• Develop and maintain test suites (unit, integration, and end-to-end) for UI reliability.
• ApplyDevOps/GitOpspractices for automated testing, deployment, and monitoring.
• Mentor engineers and scientists, driving technical quality and ensuring extensibility and performance across evolving use cases.

Qualifications

• B.S. in Computer Science, Engineering, or related field, with6+ yearsof professional software development experience.
• Expertise with modern front-end frameworks and tools, includingReact.js, TypeScript, Tailwind CSS, Redux Toolkit, Playwright, and Shadcn.
• Strong experience withNode.js.
• Skilled in writing and maintaining comprehensive test suites (Jest, React Testing Library, Cypress).
• Experience with system design, performance optimization, observability, and operational excellence for parallel LLM workloads.
• Strong intuition for UX design and a passion for building intuitive, workflow-first products.
• Excellent communication skills and a collaborative mindset in fast-moving, cross-functional environments.

Preferred Qualifications