Founding Full Stack Engineer

Gravity is building the advertising network for AI chat. We enable advertisers to embed ads directly into relevant AI conversations. Ads write themselves using AI, are context-aware, and are delivered in real time at scale.

We launched 3 months ago and already support 16M users across installed platforms. We have $500M per year in advertiser spend waiting to onboard. Impressions are scaling 10x month over month as we connect supply with demand. We are competing head to head with two credible platforms and moving faster.

We are a small, focused founding team building in San Francisco. We work intensely, ship daily, and operate with founder-level urgency.

We are looking for an exceptional Full Stack Engineer to help build the core systems that power AI-native advertising. You will work across the stack, own critical infrastructure and product surfaces, and help shape the technical foundation of the company from day one. This role has direct impact on scale, reliability, and revenue.

As a Founding Full Stack Engineer, you will work across our entire stack to build and scale a real-time contextual advertising network for AI tools. You will have significant influence over technical direction, architecture, and product decisions.

Our immediate priority is backend and infrastructure, but strong full-stack experience is a major plus.

This is a true founding role with autonomy, ownership, and responsibility from day one.

• Build and scale core backend infrastructure for real-time ad serving and bidding
• Own large parts of the frontend and backend codebase end to end
• Solve novel technical and product problems with high ambiguity
• Implement AI-powered features across the stack
• Design systems that scale with real production traffic
• Ship quickly, iterate daily, and make pragmatic decisions
• Work closely with the CEO on technical direction and execution

• Exceptional proficiency building products full stack. We care about ability, not years of experience
• Strong experience with Python, , and React
• Experience with distributed systems and scaling infrastructure
• Familiarity with PostgreSQL, Redis, and vector embeddings
• Hands-on experience with LLMs and AI infrastructure
• Comfort operating in ambiguity and owning outcomes
• Strong communication and founder-level accountability
• You default to action, value signal over noise, and move with urgency

• Salary: $175,000 - $300,000 USD depending on scope and impact
• Equity: $100,000 - $300,000 USD based on experience and contribution
• Location: This role will transition to on-site in San Francisco as we establish our office

• Work on cutting-edge AI monetization problems
• Shape the future of generative advertising
• Flat hierarchy with real ownership
• Small, elite, fast-moving founding team
• Massive real-world scale already in production

Compensation Range: $175K - $300K