Software Engineer, Horizon

About us

Sierra is the leading platform for customer-facing AI agents, working with many of the world's biggest brands — including The GAP, Rocket Mortgage, SoFi, Sutter Health, and SoftBank — to transform how they serve customers and grow their businesses. We are primarily an in-person company based in San Francisco, with growing offices across North America, Europe, and Asia.

Our co-founders are Bret Taylor and Clay Bavor. 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 primitives for self improvement: Create the feedback loops, evaluation systems, memory, signals, and decisioning infrastructure that help long-running agents learn from outcomes and improve over time.
• Build the future of long-horizon agents: Design and ship agents that pursue complex business outcomes over days, weeks, or months across voice, SMS, email, and other channels.
• Turn 0-to-1 work into a platform: Identify patterns and build reusable systems, abstractions, and tools that make future Horizon agents faster and easier to launch.
• Solve technically complex problems: Build across orchestration, integrations, data, memory, signals, decisioning, observability, and multi-channel engagement.
• Shape the Horizon product: Surface platform gaps through hands-on implementation and work with product and engineering to define Horizon’s architecture and roadmap.
• Create a clean path beyond the POC: Once a solution is validated, translate what you built into durable product capabilities and enable a successful handoff for continued deployment.

What you’ll bring

• Experience building and scaling end-to-end production systems.
• Strong platform and systems engineering fundamentals.
• The ability to move between customer problems, product design, and technical implementation.
• Strong technical judgment in ambiguous, fast-changing environments.
• A builder’s mindset and the ability to take products from zero to one.
• Comfort working directly with customers and understanding complex business processes.
• High agency, adaptability, and clear communication.
• At least two years of professional software engineering experience
• Experience with Python, TypeScript, or Go and React.

Even better

• Experience as a founder, founding engineer, or early engineer at a startup.
• Experience building workflow, orchestration, event-driven, or distributed systems.
• Experience developing platforms or reusable infrastructure for other engineers.
• Experience building or deploying AI and LLM-powered products.
• Familiarity with enterprise integrations, APIs, data pipelines, and systems of record.
• Experience working in complex industries such as financial services or healthcare.

What we offer

We want our benefits to reflect our values and offer the following to full-time employees:

These benefits are further detailed in Sierra's policies, may vary by region, and are subject to change at any time, consistent with the terms of any applicable compensation or benefits plans. Eligible full-time employees can participate in Sierra's equity plans subject to the terms of the applicable plans and policies.

Be you, with us

We encourage you to apply even if your experience doesn't precisely match the job description. We strive to evaluate all applicants consistently without regard to race, color, religion, gender, national origin, age, disability, veteran status, pregnancy, gender expression or identity, sexual orientation, citizenship, or any other legally protected class.