Software Engineer, Agent Harness — Sim

Sim, an AI startup focused on automating knowledge work, is hiring a Software Engineer for its Agent Harness team in San Francisco, offering $210k–$260k base salary plus 0.2%–0.8% equity. The role involves building the agent that creates workflows, tables, and knowledge bases, requiring expertise in LLM behavior and robust infrastructure for 100,000+ builders.

Software Engineer, Agent Harness - Salary - $210k–260k/yr - Location - San Francisco - Work type - On-site - Posted - 1d ago Apply on company site opens in new tab https://jobs.ashbyhq.com/sim/8bb8c0ec-babf-4923-ae78-7e35bee2cca6/application Our mission is to automate knowledge work. The first step in our journey is to build the best tool for teams to build agents. Sim is talent-dense. We're looking for special people who are mission-driven, passionate, and creative. About the Role The agent harness is Sim. It's the agent that builds workflows, tables, creates knowledge bases, and does everyday tasks. As a member of this team, you'll build the agent that builds everything else: how it plans, calls tools, uses memory, recovers from failure, and runs reliably at scale for 100,000+ builders. You may be a fit if - You can think clearly about LLM behavior tool calls, context, retries, evals and you can turn that intuition into robust infrastructure. Compensation $210K–$260K base plus 0.2%–0.8% equity. Applying If there appears to be a fit, we'll reach out to schedule 1-2 short technicals. After, we'll schedule an onsite in our office, where you'll work on a small project, discuss ideas, and meet the team. Equal Opportunity Sim is committed to creating an inclusive environment for all employees. We celebrate diversity and are committed to creating an inclusive environment for all team members. We do not discriminate on the basis of race, religion, color, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status.