Software Engineer, Agent Harness
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.
Check your resume against this role
Drop your resume. You get a 0-100 fit score against the actual job description, plus the reasoning and the gaps worth closing first. Private to you.
Score this once, or every future role
Start the candidate journey and every new role on the board gets scored against you.
Five minutes. Tell us what you’re after, drop your resume once, pick how we should reach out. You get a candid read back and you only hear from us when a role fits.