Senior Platform Engineer - AI Agent Runtime

TechTree; San Francisco (CA); On-site; USD 180,000 - 240,000; Full time

Benefits offered by this job

Health insurance

Dental

401(k) plan

Generous PTO

Gym budget

Lunch

Job summary

TechTree in San Francisco (Presidio) is seeking a senior backend engineer to build the agent runtime that coordinates tool calls, sessions, and long-running tasks. You will decide when work lives as an actor or a job, and shape how code changes resume in-flight processes.

This role emphasizes production-grade systems, concurrency, and robust tracing, with a focus on TypeScript, Cloudflare Workers, and a durable execution model. In-person, 5 days/week in the Bay Area.

Qualifications

• Experience building stateful backend systems in production.
• Ability to explain the tradeoffs between actors, background jobs, or simpler services.
• Experience debugging concurrency, retries, or recovery in code you own.
• Proficiency with TypeScript and backend-focused tooling.

Responsibilities

• Agent runtime: build and improve the runtime that starts agent work and carries session state across tool calls.
• Actors vs. jobs: choose between actors and jobs for different work and handle overlapping sessions.
• Deploys with work in flight: design long-running processes that drain or resume across releases.
• Retries and timeouts: handle failure around tool calls, including partial successes.
• Traceability: make runtime failures traceable and fix execution paths in production.

Skills

TypeScript

Backend systems

Concurrency handling

System design

Tools

Cloudflare Workers

Durable Objects

Postgres

Docker

Job description

TechTree in San Francisco (Presidio) is seeking a senior backend engineer to build the agent runtime that coordinates tool calls, sessions, and long-running tasks. You will decide when work lives as an actor or a job, and shape how code changes resume in-flight processes.

This role emphasizes production-grade systems, concurrency, and robust tracing, with a focus on TypeScript, Cloudflare Workers, and a durable execution model. In-person, 5 days/week in the Bay Area.