<div>After years of working in the Tech industry, we create HRBaires, a diversified consulting firm. A team with more than 10 years of experience in recruitment, staffing, compensation &amp; outsourcing. We serve as strategic and operational HR partner aligning the business to their needs in Argentina and abroad.</div>

HRBaires

Location: San Francisco, CA (On-site, 5 days/week) Employment: Full-time Seniority: Mid-Senior Level Salary: $180,000 – $240,000 Visa: US work authorization required.&nbsp;
About the company Y Combinator-backed, early-stage AI startup (~15 people) building a hybrid AI and software platform centered on a shared context engine.
The role You’ll build and own the core execution engine (agent runtime) that manages session state, tool calls, and long-running processes — the backbone that lets AI agents operate reliably over extended sessions.
Core stack: TypeScript, Cloudflare Workers, Durable Objects, Postgres, Docker, Distributed Systems
Required
<ul>
<li>Production experience building and operating stateful backend systems — work that outlasts the initial request</li>
<li>Professional experience writing production backend code in TypeScript</li>
<li>Based in the San Francisco Bay Area, or willing to relocate</li>
</ul>
Nice to have
<ul>
<li>Experience building an agent runtime or agent harness</li>
<li>Production experience with Cloudflare Workers, Durable Objects, or other actor-based runtimes</li>
<li>Experience deploying long-running processes that persist across code releases</li>
<li>Background at next-gen AI/agentic companies or design-first product orgs</li>
</ul>
Interview process
<ul>
<li>Application review (resume + short questions)</li>
<li>15-min intro call</li>
<li>45-min technical interview</li>
<li>System design interview</li>
<li>Paid work trial (~5 days)</li>
</ul>
.