Fullstack Software Engineer, RL & Agent Researcher at Sepal AI (S24)
$135K - $155K  •  0.30% - 0.60%
Data Development for Advanced AI
San Francisco, CA, US / Remote (CA, US)
Full-time
US citizen/visa only
3+ years
About Sepal AI

Sepal AI specializes in PhD-level experts for AI model development. We provide robust, frontier data through a comprehensive process in sourcing, vetting, matching, trials, and peer quality control. We are currently working with the world's leading foundational AI model companies across domains in advanced sciences, professional services, and safety & preparedness.

About the role

Background

Sepal AI equips the world’s most ambitious AI teams with expert-grounded data, enabling faster, safer, and more responsible AI deployment. Trusted by leading research labs and global enterprises, Sepal AI builds at the frontier of intelligence by bridging exceptional human expertise with cutting-edge AI.

We’ve built the largest global talent graph and tooling to deliver proprietary training datasets and reinforcement learning environments that improve models. Relied on by top labs and enterprises, our platform drives innovation for researchers while upholding the highest standards of quality, clarity, and trust.

Sepal AI was founded in 2024 by engineers + operators from Vercel + Turing. In less than a year, we’ve closed several fortune 500s + top AI research labs as customers.

Responsibilities

As a software engineer, you’ll develop innovative full-stack applications and AI-enabled tooling that helps us scale our talent pool and data operations. You’ll be instrumental in enabling our customers - industry leaders and top AI research labs - to build, test, and evaluate their newest most powerful models with unparalleled precision, speed, and safety. You should be ready to build quickly.

Who we’re looking for

  • 3+ years of professional experience writing code and shipping products quickly end-to-end.
  • Strong proficiency in learning new languages + frameworks and applying them quickly.
  • Experience integrating LLM contexts + RAG into applications.
  • Experience with crafting user interfaces and using your instincts in product design.

Bonus points if you have

  • Experience with Reinforcement Learning Environments
  • Familiarity or prior experience with ML infrastructure, model deployment pipelines, or data operations systems.
  • Experience training models or building model annotation platforms.

Why Sepal AI?

  • Join a rapidly growing company at the forefront of the AI frontier, partnered with the world’s top research labs and enterprise AI teams.
  • Competitive compensation package, including substantial equity.
  • Robust career growth opportunities and the chance to significantly impact the future direction of AI development.
  • Exceptional health, dental, and vision coverage with generous benefits fully covered by Sepal AI.
  • Flexible PTO and work-life balance designed around empowering productivity, creativity, and innovation.
  • Vibrant, collaborative team culture focused on pushing boundaries, empowering human expertise, and delivering extraordinary outcomes.

Technology

  • We use Typescript/Fastify, Python, TRPC, NextJS, and PostgreSQL in a monorepo. We prefer you have experience with at least one of these technologies.
Technology

○ Frontend Stack: Next.js (v13+), React, TypeScript ○ Backend Stack: Node.js, tRPC, Mikro ORM , PostgreSQL: ○ Infrastructure Stack: AWS/Fly.io/Vercel

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fulltimeSan Francisco, CA, US / Remote (CA, US)Frontend$135K - $155K0.30% - 0.60%3+ years

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