Helium — Full-Stack Engineer

Location: San Francisco, CA (Onsite)
Compensation: $150,000 – $250,000 base + 0.50% – 1.50% equity (founding-tier)
Visa Sponsorship: None available — US citizen or visa holder only (no $100K H-1B)
Employment Type: Full-Time

A seed-stage, YC- and Google-backed AI startup building self-improving software: AI that automatically generates, tests, and learns from new product experiences to drive revenue for leading consumer apps. The platform powers tens of millions of AI experiences per day, managing monetization experiences and auto-generating AI-driven onboarding and paywall variants. Small, talent-dense team (majority ex-founders); $6M raised, revenue doubling monthly, on track to $1M ARR with a Series A this summer.

Founded 2024 · Seed · Consumer Tech · San Francisco, CA

The company is hiring 2 full-stack engineers to own big chunks of its AI Experience Generation product serving millions of users daily. The team is not prescriptive — you are given problems and expected to propose solutions and execute them, write your own PRDs and specs, talk to customers, and own features end to end. In-office Monday to Friday, with weekend pushes common.

• Ship features on the Next.js / Golang AI Experience Generation product serving tens of millions of users daily
• Tune, optimize, and load-test servers as volume 10x's toward 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 new experiences
• Own features end to end: write PRDs and specs, ship, test, and validate against real users

• Frontend: Next.js, TypeScript / JavaScript, React
• Backend: Golang, Python
• Infrastructure: AWS

• 0 to 7 years of software engineering experience with a full-stack range (both backend and frontend)
• Backend experience (Python, Go, or infrastructure like AWS) AND frontend experience (TypeScript / JavaScript / React or modern equivalent)
• One of the following: 1.5+ years at a Tier-1 engineering team (FAANG, YC company, scale-up); ex-founder background; CS degree from an elite school; or other clear evidence of greatness (side projects, OSS, etc.)
• Open to relocating to SF and working Monday to Friday in office with frequent weekend pushes
• US citizen or visa holder (no $100K H-1B)

• Built or owned 0 to 1 products or features from scratch
• Early engineer at a startup (roughly #1 to 15) or at an early-stage startup / small product team
• LLM APIs shipped in production: prompting, RAG, agents, evals, AI workflows
• Data pipeline, ingestion, or analytics infrastructure (queues, async jobs, webhooks, ETL/ELT, workflow systems)
• Builds in public: writing, OSS, talks, Show HN, meaningful GitHub

1. Initial screen (30 min) with the CEO or CTO: background, recent project, goals
2. Technical screen (45 min) with the CTO: break down a real feature, discuss architecture, high-level coding
3. On-site (3 hours, SF): behavioral deep-dive and technical deep-dive
4. Work trial (2 to 3 days, paid, SF office): build a real feature end to end and present it
5. Offer

• Role is fully onsite in San Francisco — please only apply if you can commit to this
• No visa sponsorship available; US citizen or visa holder only

Shortlisted candidates will be contacted by David Joseph & Co., the recruiting partner managing this search.