Agent Harness Engineer - Core Runtime

We are looking for a Core Runtime engineer to own the agent harness that turns our LLMs into reliable, autonomous software. The harness is the run loop, orchestrator, and monitor that keep an agent working safely across thousands of tool calls and hours of wall-clock time. You will work at the intersection of systems engineering and applied AI, building the substrate that every SuperNinja agent runs on.

You will report to the engineering lead for agent infrastructure and will have ownership in these areas:

• Research, design, and build the core run loop and orchestration that power autonomous agents
• Define how agents manage context, recover from errors, and hand off work cleanly