
Founding RL Engineer
DavidJoseph& · San Francisco, United States
- Professional Services
- 11–50 employees
- Ottawa, Ontario
Strong hiring record · median 42 days open
Hiring signal
Actively hiring
Still listed on the employer's own board · publishes a salary range · How we score
All reasons
In its favour
- Still listed on the employer's own board
- Publishes a salary range
About the Company
Our client is a venture-backed, seed-stage AI data company based in San Francisco. They supply high-quality multilingual voice data and enterprise data to leading AI labs, and use real-world company data to build rich reinforcement learning (RL) environments rather than synthetic ones. The business already generates meaningful revenue and works with top voice and frontier AI labs. The team is small, founder-led and hiring fast.
About the Role
We are looking for a Founding RL Engineer to build high-quality RL environments and AI agents.
The role spans two streams
building RL environments from the company's proprietary voice and enterprise datasets, and building and deploying AI agents for enterprise customers.
This is the first hire on the engineering team. You will report to and work directly with both co-founders, and lead the engineering function as the team grows.
What You'll Own
- Build high-quality RL environments from proprietary voice and enterprise datasets
- Build and deploy AI agents for enterprise customers
- Partner with the co-founders on technical direction and roadmap
- Lead the engineering team as it grows
- Ship fast while holding a high-quality standard at startup pace
Must-Have Requirements
- 3-7 years of engineering experience with strong RL fundamentals
- Prior experience building RL environments, either at an RL company or at a human data company with hands-on RL exposure (e.g. Surge, Mercor, Scale-type data companies, Proximal, or comparable)
- Hands-on experience building AI agents in production
- Strong AI-native tooling fluency, using tools such as Claude Code or Cursor daily as production aids
- Based in or willing to relocate to San Francisco, working fully in person 5.5 days a week
Nice-to-Have
- Prior experience at a top human data company
- Full-stack engineering background (TypeScript, AWS)
- iOS, Swift, or React Native experience for mobile app development
- Prior startup experience with a demonstrated shipping cadence
Compensation & Benefits
- Base salary: USD $125,000 - $200,000
- Annual profit-share bonus: USD $100,000 - $200,000
- Founding engineer role with a clear path to leading the engineering team
Key Details
- Location: San Francisco, CA (fully in person, 5.5-day week, Sundays off)
- Employment: Full-time
- Experience: 3-7 years
- Visa sponsorship: Not available
Interview Process
Intro chat with a co-founder, chat with the second co-founder, take-home assignment, technical chat, and a short work trial (a couple of days). The full process can be completed in about one week.
Skills
- Claude Code
- Cursor
- TypeScript
- AWS
- iOS
- Swift
- React Native
More jobs at DavidJoseph&
All 50- Senior/Staff Software Engineer, AgentsDavidJoseph& · San Francisco, United States · USD 220,000–315,000/yr4d ago
- MTS - Product EngineerDavidJoseph& · San Francisco, United States · USD 160,000–300,000/yr11d ago
- Forward Deployed EngineerDavidJoseph& · San Francisco, United States · USD 160,000–230,000/yr11d ago
- Senior/Staff Applied AI Engineer, Agent HarnessDavidJoseph& · San Francisco, United States · USD 200,000–300,000/yr11d ago
- AI Product EngineerDavidJoseph& · San Francisco, United States · USD 200,000–300,000/yr11d ago