PB✓
PBridge

Full-time jobsthe United States

Software Engineer, Agent Architecture

sierra · San Francisco, CA · Full-time

About this role

ABOUT US

At Sierra, we’re creating a platform to help businesses build better, more human customer experiences with AI. We are primarily an in-person company based in San Francisco, with growing offices in Atlanta, New York, London, Paris, Madrid, Munich, Singapore, Tokyo, and Sydney.

We are guided by a set of values that are at the core of our actions and define our culture: Trust, Customer Obsession, Craftsmanship, Intensity, and Family. These values are the foundation of our work, and we are committed to upholding them in everything we do.

Our co-founders are Bret Taylor https://www.linkedin.com/in/brettaylor/ and Clay Bavor https://www.linkedin.com/in/claybavor/. Bret currently serves as Board Chair of OpenAI. Previously, he was co-CEO of Salesforce (which had acquired the company he founded, Quip) and CTO of Facebook. Bret was also one of Google's earliest product managers and co-creator of Google Maps. Before founding Sierra, Clay spent 18 years at Google, where he most recently led Google Labs. Earlier, he started and led Google’s AR/VR effort, Project Starline, and Google Lens. Before that, Clay led the product and design teams for Google Workspace. 

WHAT YOU'LL DO

- Build the core systems that power agents. You’ll work on the Agent SDK — the orchestration engine, runtime, and primitives that define how agents reason, take actions, and interact with users and systems.

- Design the agentic loop. What primitives do we need to build agents that are steerable and verifiable, while still conversational and adaptive? You’ll help define how agents operate in real-world environments.

- Improve retrieval and grounding. You’ll build systems that ensure agents provide accurate, trustworthy responses by effectively retrieving and using knowledge.

- Build evaluation systems. You’ll design frameworks that allow us and our customers to measure and improve agent quality over time.

WHAT YOU'LL BRING

- A passion for being on the frontier of AI products.

- Strong software engineering fundamentals and experience building production systems.

- Motivation and high-agency to drive outcomes in a high-autonomy culture.

- 4+ years hands-on experience building production products and systems.

- Degree in Computer Science or related field, or equivalent professional experience.

EVEN BETTER

- Experience building AI-powered systems or agent frameworks.

- Experience with retrieval, evaluation systems, or LLM-based applications.

- Experience building developer platforms or SDKs.

- Experience with Go and Typescript.

OUR VALUES

- Trust: We build trust with our customers with our accountability, empathy, quality, and responsiveness. We build trust in AI by making it more accessible, safe, and useful. We build trust with each other by showing up for each other professionally and personally, creating an environment that enables all of us to do our best work.

- Customer Obsession: We deeply understand our customers’ business goals and

Tired of applying one by one?

Our Career Success Team finds roles in the United States that fit you, tailors your CV to each, and submits the applications — tracked end to end. You just show up to interviews.

We apply, you interview →