Founding Engineer — Enterprise AI Systems (Equity)

Ambral (YC S25); San Francisco (CA); On-site; USD 150,000 - 190,000; Full time

Benefits offered by this job

Significant equity and ownership

Equinox membership

Free meals, coffee, and snacks

Health insurance

Unlimited PTO

Job summary

Ambral, a YC S25-backed startup, is building a replayable environment engine over real enterprise history and deploying it within modern workflows. You’ll work closely with the CTO to turn historical data into scalable, model-improvement systems and help ship production-grade infrastructure.

We value ownership, collaboration, and building something you can be proud of for decades. Join us as we scale from founding team to deployment across enterprises.

Qualifications

• 2+ years of experience building production software or in a quant role.
• Ability to process large, messy datasets at scale.
• Able to translate fuzzy business objectives into measurable tasks.
• Capable of moving between research questions and production work.

Responsibilities

• Build a replayable environment engine over real enterprise history.
• Architect environment factory to convert historical data into runnable environments.
• Design graders to translate objectives into verifiable rewards.
• Develop methods for mining tasks, trajectories, and evaluation cases from historical workflows.
• Create eval sets that are representative, reproducible, and resistant to overfitting.
• Improve models to maximize performance while reducing inference cost.
• Build replay and observability systems for explainable and measurable agent behavior.

Skills

Production software development

Machine learning systems experience

Quant role experience

Job description

Ambral, a YC S25-backed startup, is building a replayable environment engine over real enterprise history and deploying it within modern workflows. You’ll work closely with the CTO to turn historical data into scalable, model-improvement systems and help ship production-grade infrastructure.

We value ownership, collaboration, and building something you can be proud of for decades. Join us as we scale from founding team to deployment across enterprises.