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Clera

Founding ML Research Engineer

San Francisco
Salary
$200,000 - $300,000 annually
Level
Mid
Work type
On-site · San Francisco
Visa
Not offered

Open. First seen 15 October 2026.

Apply on the company's site →

What this role asks for

Standard for data science / ML roles

LLM · Machine Learning · Python

Common in data science / ML postings at any company.

Read against Clera's other open postings on this site.

The team: Engineering HIRES STEADILY

This role is one of 292 open in Engineering. 226 were posted in the last 30 days and the oldest in March: a team that hires all year rather than one being built.

WHAT THE TEAM WORKS WITH, ACROSS ITS POSTINGS

LLM (135 of 292), TypeScript (131 of 292), Python (123 of 292), React (107 of 292), Machine Learning (70 of 292), PostgreSQL (58 of 292), JavaScript (55 of 292)

OTHER ROLES ON THIS TEAM

From the team and dates on Clera's own job board.

About the role

About the Role

Join the founding team at a Y Combinator-backed AI assistant startup to build the models and systems behind a useful, reliable AI agent. You will lead hands-on research and engineering that improves answer quality while managing latency, cost, and safety, and ship improvements to users regularly.

What You'll Do

  • Build evaluation harnesses using model judges, human preference data, and regression tests to guide release decisions.
  • Post-train models through supervised fine-tuning, preference tuning, and distillation, then ship the results to production.
  • Develop model routing that balances answer quality, latency, and cost across smaller and frontier models.
  • Improve agent performance on websites without APIs, including navigation, sign-in, and checkout, with appropriate escalation when needed.
  • Identify and address prompt injection, data leakage, and other risks through adversarial testing and evaluations.
  • Advance memory, retrieval, tool selection, and decisions about when the agent should act or ask for help.
  • Review real conversations and turn findings into evaluation and model improvements.

What We're Looking For

  • At least 4 years of ML or software engineering experience at an AI lab, AI product company, or similar organization.
  • Hands-on experience fine-tuning or post-training LLMs and deploying the results to production.
  • Experience designing evaluations that teams have used to make product release decisions.
  • Background in at least one area: LLM red teaming, browser or computer-use agents, model routing, or production agents with tools and persistent memory.
  • Strong Python skills and experience with ML training and evaluation tools, plus TypeScript experience in a product codebase.
  • A hands-on, founding-team approach, with interest in setting technical direction and helping grow the team.

Compensation & Benefits

Salary range: $200,000 to $300,000 USD annually. Visa sponsorship is not available.

Location

On-site in San Francisco, California, United States.

Other openings for this role

2 open postings for this role in San Francisco, first posted 14 October 2026. The company is likely hiring for more than one position. None has been taken down and posted again.

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