CTO | AI/ML Research Startup – [$350k + equity] [SF]

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

Job summary

Rectec Recruitment is seeking a Chief Technology Officer for a stealth AI safety lab in San Francisco. You’ll own the technical vision, lead engineering, and build real-time guardrails for AI in production, starting with financial services.

You’ll hire and mentor 3–6 engineers in your first year, shape architecture with the founders, and ship hands-on code while guiding research directions in a fast-paced, high-agency environment.

Qualifications

• 5–10 years of experience as a CTO, Head of Engineering, or engineering leader.
• Experience building AI/LLM products and eval harnesses.
• Experience with agent RAG, forward-deployed work, or on-prem models.
• Builder-first co-founder profile, currently writing code and shipping.
• US work authorization (visa transfers acceptable).
• Experience at fast-paced companies (Ramp, Mercury, Kalshi, or Perplexity).

Responsibilities

• Build legal evaluations (RL environments) to measure AI’s failure modes in financial services.
• Productionize the research MVP into real-time guardrails for design partners.
• Set technical architecture and research direction alongside the founders.
• Hire and mentor engineers to grow the engineering team.
• Collaborate with design partners to iterate on needs while building core infrastructure.

Skills

Engineering leadership

CTO experience

AI/LLM product experience

RAG / agent tech

Infrastructure development

Code and shipping

US work authorization

Education

University degree

Tools

Evaluation environments

Training pipelines

Job description

The project is an AI safety applied-research lab on a mission to make AI agents follow the law in the real world. Founder spent nine years working on AI safety across Stanford, the US government (where she helped start the Center for AI Standards and Innovation), Scale AI, and Harvard Law/MBA — alongside her co-founder, a researcher and postdoc at MIT and Harvard.

The company has raised $9.2 million in pre-seed funding, and is currently a small, rapidly growing team of engineers, legal experts, and researchers based in San Francisco. The company builds evaluations that identify AI’s legal failure modes, training environments that reduce them, and real-time guardrails that enforce compliance in production — starting with financial services as their first vertical. The company is still in stealth with limited public information but has already engaged design partners eager for their technology. The culture is fast-paced, research-driven, and high-agency — a team of “super-learners, believers, and doers” who embrace uncertainty, ask hard questions, and ship solutions to frontier problems that have no predefined answers.

We are looking for a Chief Technology Officer with 5+ years of experience to own the technical vision and lead engineering at a well-funded AI safety applied-research lab. You’ll work alongside the founders to build evaluations that identify AI’s legal failure modes, create training environments that reduce them, and ship real-time guardrails that enforce compliance in production — starting with financial services.

What will you be doing?

• Building legal evaluations (RL environments) to measure AI’s failure modes in financial services
• Productionizing the existing research MVP into real-time guardrails for design partners
• Setting technical architecture and research direction alongside the founders
• Hiring and mentoring 3-6 engineers in your first year to build out the engineering team
• Working hands-on with design partners — iterating directly on their needs while building core infrastructure

Requirements

• Experience hiring engineers, growing teams, and ++building systems from 0- 1++
• Experience building eval harnesses, RL environments, or training pipelines
• 5 – 10 years of experience as a CTO, Head of Engineering, or engineering leader
• Experience building and deploying AI or LLM products
• Experience with agent RAG, forward- deployed work, on- prem models, or building evaluation and testing environments
• Experience building core infrastructure
• Builder- first co- founder profile, currently writing code and shipping, not managing from a distance
• US work authorization (visa transfers acceptable)
• Experience at fast- paced companies (Ramp, Mercury, Kalshi, or Perplexity)
• Strong university background