Backend Software Engineer

Full-time, mid-level, on-site role in San Francisco, CA.

About the role

Zof AI is seeking a Backend Software Engineer to own the services, APIs, and data layer that our agent fleets run on. This role covers job orchestration and queueing for long-running agent runs, Postgres schema and query performance, and the storage paths for the evidence and validation artifacts every fix we ship depends on.

If you have worked as a Backend Software Engineer, API Engineer, Platform Engineer, or Distributed Systems Engineer, this is that discipline at Zof AI.

The ideal candidate writes clear, well-tested services, reasons carefully about failure and state, and treats throughput, correctness, and cost as everyday engineering constraints.

Daily hands-on use of AI coding agents to design, build, and debug backend systems is required.

Responsibilities

• Design, build, and operate the services and APIs our agent fleets run on.
• Build the job orchestration and queueing that keeps long-running agent work moving.
• Own Postgres schema design, migrations, and query performance as data grows.
• Ship the storage and retrieval paths for the evidence and traces every agent run produces.
• Instrument services so failures are observable, debuggable, and recoverable.
• Harden reliability with testing, retries, idempotency, and backpressure under real load.
• Partner with product and AI engineers to turn agent behavior into stable interfaces.
• Own backend systems from design through production.

Requirements

• Experience building and shipping backend services in production.
• Strong software engineering foundation.
• Working knowledge of relational databases and SQL, ideally Postgres.
• Familiarity with APIs, queues, and asynchronous job processing.
• Ability to debug performance and correctness issues in running systems.
• Habit of proving your work with tests and evidence before it ships.
• Clear written and verbal communication.
• Comfort operating in a fast-moving environment.

Nice to have

• Experience with TypeScript, Node.js, Python, Postgres, or similar technologies.
• Experience with distributed systems, event-driven architecture, or streaming pipelines.
• Experience with cloud platforms, containers, and CI/CD.
• Experience supporting AI or agent workloads in production.