Staff Backend Software Engineer Company: Confidential — first outbound operating system for SMS Location: San Francisco, CA (in office 5 days per week) Compensation: $225,000 - $300,000 + competitive equity Employment Type: Full-time Visa Sponsorship: Not available (US citizens and green card holders) About the Company The client is the first outbound operating system for SMS, giving enterprise brands AI-first infrastructure to deliver campaigns at scale across enterprise, SMB and political messaging. It delivers billions of messages a month. Founded in 2023, the client recently raised a $50M Series A from top-tier investors and is a team of about 18. The Role The client is hiring a Staff Backend Software Engineer (6+ years) to own and build the core backend systems behind its highly scalable SMS messaging infrastructure. You will join a small, elite team with massive technical impact, and should have strong career velocity and a record of building 0-to-1 products at high-growth startups (pre-seed to Series B). What You Will Do • Own and build core backend systems across routing, messaging, delivery and automation. • Design and ship scalable services handling billions of messages a month. • Drive 0-to-1 development of entire product surfaces, not just features. • Work closely with a lean engineering team. • Solve hard infrastructure problems at scale while moving quickly from idea to production. What You Bring • 6+ years of backend engineering experience • A record of building 0-to-1 products at high-growth startups (pre-seed to Series B) • Experience with high-scale, queue-based infrastructure • Node.js/TypeScript and AWS experience • Ability to work in the San Francisco office 5 days a week • US work authorization without sponsorship Tech Stack Node.js, TypeScript, AWS, SQS, queue-based infrastructure Before you apply: get a free recruiter-readiness score for your resume at CareerStanding — about a minute, no signup, and your resume stays in your browser.