Software Engineer, Platform / Applied AI (Full-Stack)

San Francisco, CA · On-site · Full-time Compensation: $180,000–$220,000 + competitive equity (4-year vest)

About the Company

Our client is an applied AI research lab investigating the boundaries and capabilities of AI through novel datasets and experimentation. Its customers are the foundation-model labs — it serves the frontier AI labs. It reports $25M+ annualized revenue, is one of the fastest-growing companies in its cohort, and is well-backed by top-tier investors, with a founding team from top quant firms, big tech, and leading AI research labs.

Founded 2025 · 11–50 people · Industry: AI / Data

The Role

As a core/founding engineer, you'll build the data infrastructure shaping frontier-model development, owning projects end to end across frontend, backend, and infrastructure.

Tech stack: Next.js / JavaScript / TypeScript, Python, Go · GCP/AWS (serverless, cloud functions) · Kubernetes · Redis · Elasticsearch · Kafka / RabbitMQ · NoSQL · APIs.

Requirements

• From a top university (US/Canadian/UK), a top quant firm, or with founding-engineer experience
• Strong coding fundamentals in Node.js / TypeScript, Python, and/or Go
• Deep understanding of distributed systems, scalability challenges, and system design
• Familiarity with cloud platforms (GCP/AWS), Kubernetes, APIs, and NoSQL databases
• Able to reason about trade-offs and balance speed vs reliability
• Strong communication and a bias toward ownership, curiosity, and simple solutions to complex problems
• Bonus: experience with RL environments, agentic systems, or human-in-the-loop workflows

Nice to Haves

• An active GitHub — a builder at heart
• Experience with AI agents and RL environments
• A top quant firm or founding-engineer background (or multiple internships) at high-growth startups
• Has trialed or succeeded in past fast-paced startup roles with strong references
• Works autonomously yet collaboratively, comfortable with an intense pace
• Ex-founders whose product was genuinely sophisticated and complex

Why Join

• Founding ownership: one of the first hires; own entire projects end to end and define the data infrastructure from day one
• Frontier impact: build the data infrastructure shaping frontier-model development, with the frontier AI labs as direct customers
• Trajectory and backing: one of the fastest-growing companies in its cohort, $25M+ annualized revenue, with a path to lead and grow an engineering team
• Comp and perks: competitive salary + equity (4-year vest), daily lunch and dinner, free gym membership, health insurance

Details

• Location — San Francisco, CA
• Work policy — On-site
• Compensation — $180,000–$220,000 + competitive equity (4-year vest)
• Visa sponsorship — Available (O-1, OPT)
• Employment type — Full-time