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# Senior Platform Engineer

- **Company:** SAUNA LLC
- **Location:** San Francisco, CA, United States
- **Experience:** Expert
- **Salary:** $180,000.0 - $240,000.0
- **Contract:** Permanent contract
- **Skills:** PostgreSQL, TypeScript, Backend, Cloudflare, Software Coding, Docker
- **Published:** October 8, 2026
- **Apply:** https://www.adzuna.com/details/5920338221

## About the Role

Stack: TypeScript, Cloudflare Workers, Durable Objects, Postgres, Docker. Experience with comparable runtimes counts., * You've built and operated stateful backend systems in production, including work that outlasts the request that started it.

 * You can explain a decision you made between an actor, a background job, or a simpler service, and show what you shipped.
 * You've debugged concurrency, retries, or recovery in code you've owned.
 * You're productive in TypeScript and want to keep writing code as your scope grows.

Bonus

 * You've worked on an agent runtime or agent harness.
 * You've worked with Cloudflare Workers, Durable Objects, or another actor-based runtime.
 * You've deployed long-running processes that persist or resume work across a code release.

## Description

Sauna's agent runtime has to keep track of work when a tool fails or new code ships mid-task. One session might start with a message, check Calendar, draft a Slack reply, and update Linear after the first response. A tool call can time out after the action succeeds; the runtime needs to know what happened before retrying., * Build and improve the runtime that starts agent work, carries session state through tool calls, and resumes interrupted runs.

 * Choose between actors and jobs for different kinds of work. Implement the choice and check how it behaves when sessions overlap.
 * Design how long-running processes drain or resume when code changes, keeping in-flight work accounted for across releases.
 * Handle retries and timeouts around tool calls, including cases where an external action succeeded but the response never came back.
 * Make runtime failures traceable. Find why a run stopped or stalled, fix the execution path, and see the change through to production.