# Software Engineer, Agent Harness at Sim

- Company: Sim
- What the company does: Sim is the open-source AI workspace where companies build, distribute, and govern AI agents. Hundreds of integrations, every major LLM, permission groups, spend limits, and self-hosting. Backed by Y Combinator.
- Company website: https://sim.ai
- Type: Startups (AI role)
- Level: Mid level
- Location: San Francisco
- Work setup: On-site
- Pay: $210K to $260K base salary per year (USD)
- Posted: 2026-08-26
- Apply by: 2026-10-10
- Apply: https://jobs.ashbyhq.com/sim/8bb8c0ec-babf-4923-ae78-7e35bee2cca6
- Page: https://www.1752.vc/careers/jobs/sim-software-engineer-agent-harness/

## About the role

Sim is talent-dense. We're looking for special people who are mission-driven, passionate, and creative. 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.

Tags: Engineering