Staff Application Engineer

About Keystone.AI

Keystone.AI

employs the world’s best AI/ML science and technology practitioners with unparalleled experience implementing highly complex, massive-scale algorithms and models to help companies make better decisions across manufacturing, supply chain management, sales, and marketing.

We are headquartered in

Bellevue, WA

, our team operates within a flexible, hybrid working model.

About the role

We are seeking a

Staff Application Engineer

to lead the frontend and application architecture for our decision-intelligence platform. In this end-to-end builder role, you will bridge Application Engineering, Product, Design, Science, and Customer Success to translate sophisticated data science and operations research into intuitive enterprise software.

What you'll do

• Application & Systems Architecture: Architect, build, and maintain production web applications using React and TypeScript. Define API contracts and system interfaces to deliver data-intensive science as a cohesive enterprise platform.
• Science to Product Integration: Transform statistical forecasts, optimization models, simulation outputs, uncertainty modeling, and scenario trade-offs into actionable, intuitive product features.
• Platform Frameworks: Establish modular, reusable frontend component libraries and application frameworks enabling scientific teams to launch new capabilities rapidly and scalably.
• Quality, Security & Scale: Uphold high standards for performance, accessibility, security, and data governance when handling large, complex enterprise datasets.
• Cross-Functional Leadership: Partner with product, design, engineering, and clients to turn bespoke implementations into core product features. Mentor engineers and establish architectural best practices.

Basic Qualifications

• Proven experience building sophisticated production applications at a Staff level or equivalent depth.
• Deep expertise in modern web tech stacks (React, TypeScript, JavaScript, HTML, CSS) and state management.
• Solid software engineering fundamentals across APIs, testing, performance, observability, and production reliability.
• Experience building data-intensive, analytical, scientific, or enterprise applications handling large datasets.
• Strong product intuition, UX/interaction design judgment, and ability to shape ambiguous requirements into fluid workflows.
• Familiarity with enterprise concerns including auth, permissions, security, and customer isolation.
• Excellent technical communication, leadership, and mentorship capabilities in dynamic startup environments.

Preferred Qualifications

• Experience with ML, forecasting, optimization, simulation, or decision science workflows.
• Proficiency with data visualization tech (D3, SVG, Canvas, WebGL, Vega, Observable Plot).
• Background in supply chain, manufacturing, logistics, or operations research domains.
• Experience in Forward Deployment or client-embedded engineering environments.

Benefits

Discretionary annual performance bonus, 401(k) matching contribution, and comprehensive healthcare coverage.