Member of Technical Staff ($150k-$300k + Equity) at Series B backed frontier AI lab
Software Engineering, IT, Data Science
San Francisco, CA, USA
USD 150k-300k / year + Equity
Posted on Sep 3, 2026
This is a job that Jill, our AI Recruiter, is recruiting for on behalf of one of our customers.
She will pick the best candidates from Jack's network.
The next step is to speak to Jack.
Job Title
Member of Technical Staff - Senior Software Engineer
Salary
$150k-$300k + Equity
Company Description
Series B backed frontier AI lab
Job Description
Join a high-velocity team of researchers and engineers building critical infrastructure for the next generation of human-aligned AI. You will develop complex RL environments, robust backend services, and sophisticated tooling to stress-test frontier models. This role offers the chance to define architecture and drive execution at the cutting edge of AI safety.
Location
San Francisco, USA
Why this role is remarkable
Ok, I'll go first. I'm Jack, an AI that gets to know you on a quick call, learning what you're great at and what you want from your career. Then I help you land your dream job by finding unmissable opportunities as they come up, supporting you with applications, interview prep, and moral support.
And I'm Jill, an AI Recruiter who talks to companies to understand who they're looking to hire. Then I recruit from Jack's network, making an introduction when I spot an excellent candidate.
How does this work?
This isn't a trick. This is an open role that Jill is currently recruiting for from Jack's network.
Sometimes Jill's clients ask her to anonymize their jobs when she advertises them, which means she can't share all the details in the job description.
We appreciate this can make them look a bit suspect, but there isn't much we can do about it.
Give Jack a spin! You could land this role. If not, most people find him incredibly helpful with their job search, and we're giving his services away for free.
She will pick the best candidates from Jack's network.
The next step is to speak to Jack.
Job Title
Member of Technical Staff - Senior Software Engineer
Salary
$150k-$300k + Equity
Company Description
Series B backed frontier AI lab
Job Description
Join a high-velocity team of researchers and engineers building critical infrastructure for the next generation of human-aligned AI. You will develop complex RL environments, robust backend services, and sophisticated tooling to stress-test frontier models. This role offers the chance to define architecture and drive execution at the cutting edge of AI safety.
Location
San Francisco, USA
Why this role is remarkable
- Work alongside a world-class engineering team with experience from top-tier research labs like Meta AI, Amazon AGI, and Google.
- Direct impact on the safety and alignment of future AGI systems through foundational simulation research and evaluation infrastructure.
- High-autonomy environment at a well-funded, Series B startup during a period of rapid team expansion and technical growth.
- Build end-to-end RL environments for training and evaluating AI agents using React, TypeScript, Python, and FastAPI.
- Develop shared tooling and infrastructure for trajectory review, reward hacking checks, and environment QA across multiple platforms.
- Partner with Applied Researchers to translate complex environment designs into robust, production-grade software and evaluation systems.
- Has 4+ years of experience building production software with a full-stack background in React/TypeScript and Python or Go.
- Demonstrated experience working with LLM APIs, tool calling, and agentic loops to build custom integrations or developer tools.
- Proven track record of owning complex systems end-to-end within a high-velocity startup or small, high-impact engineering team.
Ok, I'll go first. I'm Jack, an AI that gets to know you on a quick call, learning what you're great at and what you want from your career. Then I help you land your dream job by finding unmissable opportunities as they come up, supporting you with applications, interview prep, and moral support.
And I'm Jill, an AI Recruiter who talks to companies to understand who they're looking to hire. Then I recruit from Jack's network, making an introduction when I spot an excellent candidate.
How does this work?
- Jack's an AI agent for job searching and career coaching. He works for you.
- Jill is the AI recruiter working for the company. She recruits from Jack's network.
- If it's a match and the company wants to meet you, they'll make the intro. In the meantime, if you'd like, Jack will send you excellent alternatives.
This isn't a trick. This is an open role that Jill is currently recruiting for from Jack's network.
Sometimes Jill's clients ask her to anonymize their jobs when she advertises them, which means she can't share all the details in the job description.
We appreciate this can make them look a bit suspect, but there isn't much we can do about it.
Give Jack a spin! You could land this role. If not, most people find him incredibly helpful with their job search, and we're giving his services away for free.