Senior Platform Engineer, High-Scale AI & Sailboxes

Theory Ventures; San Francisco (CA); On-site; USD 180,000 - 280,000; Full time

Benefits offered by this job

Meals provided

Studio Display at desk

Coffee/tea options in office

Cat visits

Job summary

Sail is hiring an engineer to join Sailboxes, the cost-efficient CPU sandbox for long-horizon agents, in our San Francisco office. You’ll work across the stack, from FirecrackerVM tuning to large-scale systems that maximize efficiency and scale.

You’ll model usage patterns, design smarter scheduling, and build monitoring tooling to ensure a robust, scalable platform for both humans and agents. This is a hands-on, product-focused role.

Qualifications

• Strong distributed systems fundamentals (concurrency, networking, databases, performance engineering).
• Experience with cloud infrastructure (GCP, AWS, Azure), container orchestration, and multi-cloud networking.
• Product-focused approach to platform work, robust, scalable, ergonomic for users.
• Bonus: experience with FirecrackerVMs.

Responsibilities

• Dig into the guts of our custom FirecrackerVM fork to extract every ounce of performance possible from our platform.
• Model historic usage patterns and implement scheduling algorithms that maximize fleet utilization and autoscale intelligently while minimizing latency.
• Design and implement highly-available distributed systems to handle millions of operations per second.
• Build deep monitoring tooling and features that make Sailboxes the most delightful experience for both humans and agents alike.
• Own future product directions for Sailboxes (Windows/Mac sandboxes, high-efficiency storage, etc.).

Skills

Distributed systems

Cloud infrastructure

Product-focused

FirecrackerVMs

Job description

Sail is hiring an engineer to join Sailboxes, the cost-efficient CPU sandbox for long-horizon agents, in our San Francisco office. You’ll work across the stack, from FirecrackerVM tuning to large-scale systems that maximize efficiency and scale.

You’ll model usage patterns, design smarter scheduling, and build monitoring tooling to ensure a robust, scalable platform for both humans and agents. This is a hands-on, product-focused role.