Staff Application Engineer

About Keystone.AI

Keystone.AIemploys the world’s best AI/ML science and technology practitioners with unparalleledexperience implementing highly complex, massive-scale algorithms and models to help companiesmake 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

Key Responsibilities

• 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

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