Backend Engineer, Applied AI (US)

We are looking for a Backend Engineer, Applied AI with 6, 10 years of experience to build and scale real-time systems serving millions of daily users at Citizen, the #1 public safety app in the U.S. You're someone who's obsessed with the latest AI model releases, attends meetups, and uses tools like Cursor, Claude, and Codex every single day, not just to write code, but to rethink how entire systems scale. Ideally you have a founder or early-stage startup background and have personally owned backend systems at consumer scale. We're looking for someone who can bring both distributed systems depth and a forward-thinking AI-native mindset to a team that ships fast and builds things that matter.

What will you be doing?

• Scaling backend systems that serve 1M+ daily active users across real-time pipelines, live video infrastructure, and notification delivery

• Driving AI adoption across the backend, designing systems to be more agent-friendly, building verification pipelines, and proposing where agents can run autonomously

• Owning critical pieces of the core system end-to-end, from the real-time 911 ingestion pipeline to enterprise APIs and internal operator tooling

• Participating in an on-call rotation (roughly one week every two months) to keep Citizen's 24/7 safety platform running

• Working daily with iOS, Android, ML, Data, and Mission Control teams to ship measurable improvements in latency, correctness, and cost