Software Engineer, Horizon

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:

• Flexible (unlimited) paid time off

• Medical, dental, and vision benefits for you and your family

• Life insurance and disability benefits

• Retirement plan dependent on country of employment

• Parental leave

• Fertility and family building benefits through Carrot

• Lunch, as well as delicious snacks and coffee to keep you energized 

• Discretionary benefit stipend giving people the ability to spend where it matters most

• Free alphorn lessons

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.