Software Engineer, Payments Infrastructure

The posting, as Sierra wrote it

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.

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 a commitment to balancing Family along the way. 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

The agent must collect and use a card number but can never see it. This work sits across four hard technical domains: payments, security, real-time voice, and LLMs. Voice is the core challenge. A caller speaks or types a card number in a live, low-latency audio stream, and the digits must never reach the model, while the model stays on the call.

Sierra owns every system that touches card data, and one small team owns it end to end across three workstreams: Platform, Product, and Safety & Integrity. Customers keep their own telephony and payment gateways. Payments is live in production for some of the largest consumer enterprises, on a platform that handles hundreds of millions of calls a year. The platform is certified to PCI DSS Level 1.

• Build real-time card capture for voice: intercept keypad and spoken digits in a live audio stream, upstream of the agent runtime in a network-segmented environment, while the LLM stays live on the call. Make it work across every telephony provider and protocol Sierra supports.
• Build and extend the tokenization platform: agents receive and send short-lived tokens, and the platform swaps a token for the real value only when it calls the customer's payment gateway.
• Own the payments egress control plane: every destination for card data is approved, versioned with the agent release, and enforced by infrastructure below the application, not by convention.
• Make payment actions correct: an at-most-once action primitive in the Agent SDK, validated amounts and items, and monitoring that compares what the agent said about a payment with what really happened.
• Keep card data out of places it s

[…]
, and when it isn’t, we fix it. When we fail, we talk about it openly and without blame so we succeed the next time.

• Family: We know that balance and intensity are compatible, and we model it in our actions and processes. We are the best technology company for parents. We support and respect each other and celebrate each other’s personal and professional achievements.

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.

BE YOU, WITH US

We're working to bring the transformative power of AI to every organization in the world. To do so, it is important to us that the diversity of our employees represents the diversity of our customers. We believe that our work and culture are better when we encourage, support, and respect different skills and experiences represented within our team. 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.