Sierra
Software Engineer, Payments Infrastructure
$230K–$390K
San Francisco, CA · On-site · Full-time · Posted Oct 22, 2026
- Experience
- 5+ years building backend, platform, or infrastructure systems.
- Education
- Degree in Computer Science or a related field, or equivalent professional experience.
About the job
Build and operate secure payments infrastructure that captures and tokenizes card data while keeping it out of the live AI agent, and enables reliable payment actions across customer systems.
What you'll do
- Build real-time card capture for voice and extend tokenization so agents use short-lived tokens instead of card data.
- Own payments egress controls and correctness safeguards, including at-most-once actions, validation, and monitoring.
- Develop self-serve payments APIs and gateway middleware, and expand tokenization into a privacy vault for PII.
What they ask for
- 5+ years building backend, platform, or infrastructure systems and operating high-reliability production services.
- Strong security judgment and rigor around retries, idempotency, at-most-once behavior, timeouts, and failure handling.
- Fluency in a systems language; the posting states Sierra uses Go.
- Degree in Computer Science or a related field, or equivalent professional experience.
Nice to have
- Experience with real-time or streaming systems, applied cryptography, network isolation, cloud security, or developer platforms.
- Experience with customer-cloud deployments, customer-facing technical work, technical direction, or payments and other sensitive-data domains.
Pay
$230K – $390K (base salary)
Tools
Go, Agent SDK, Agent Studio, Ghostwriter, PCI DSS Level 1
AI focus
Build safeguards and infrastructure that let an LLM remain live on a call without seeing plaintext card numbers; detect sensitive data in the agent’s hot path and enable secure payment actions.
Model-written summary · the original posting is authoritative