Founding Sr Full-Stack Engineer

Helium is building Self-Improving Software AI that automatically generates & tests new software experiences to lift revenue. We’re… Talent-dense: 8 people, 6 engineers, 75% ex‑founders. Well‑funded with $6M from Google & leaders from OpenAI. Fast‑growing, serving tens of millions of AI experiences per day for top consumer companies. What You’ll Do Own big chunks of the AI Experience Generation product serving millions of users per day, including adding new features to the front‑end Next.js application and deploying scalable Golang code that serves thousands of requests each second globally. Tune, optimise, and load‑test our servers as we 10× our growth from tens of millions to hundreds of millions of users per day. Design data systems and ML training infrastructure that power automated experimentation at scale. Work directly with founders and customers to design, implement, and deliver the best experiences. Wear a lot more hats than listed above. What We’re Looking For Keen problem‑solving skills: cut down ambiguous problems to first principles and deliver a working solution. Strong programming / full‑stack foundation: comfortable in both backend and frontend React code. Experience working directly on user‑facing products and understanding user needs, including talking to customers. Stellar cross‑functional communication skills: adapt to our ways of working and communicate effectively. Ownership of features end to end: write PRDs / quick specs when needed and test features end to end to satisfy requirements. Experience scoping, designing, and running complex multi‑engineer projects. Experience managing or mentoring engineers. Nice To Haves Experience with ML / AI / LLM integration in applications. Experience building scalable backend systems with demanding SLAs. Background working with design tools, chat experiences, or vibe coding tools. Previous experience founding or working at a high‑growth startup. Reasons This Role Might Not Be A Fit Want to work 9‑5. Avoid Cursor or AI coding tools. Operate only on well‑written specs or be uncomfortable designing new experiences from scratch. Don’t want to talk to customers. Our Stack Next.js (React/Typescript), Zustand AI (Vercel) SDK Tailwind / Shadcn Supabase Clickhouse Golang / Fly.io Mobile: Swift, Flutter, Expo, Android Requires Bachelor’s degree or higher in Computer Science or similar fields. #J-18808-Ljbffr Helium