Founding Full-Stack Engineer — AI SaaS, On-site, Equity

davidjoseph-co; San Francisco (CA); On-site; USD 180,000 - 230,000; Full time

Job summary

davidjoseph-co is hiring a true full-stack founding engineer for a seed-stage startup in San Francisco. You’ll work directly with the technical founder across the conversational AI agent, the embeddable customer-facing experience, the internal platform, the evaluation and self-improvement pipeline, and the underlying infrastructure.

This on-site role offers rapid impact, equity, and broad scope across agents, product, evals, and infrastructure as the first engineers join the team.

Qualifications

• 1–5 years building full-stack products at a venture-backed B2B SaaS startup with real paying customers.
• Genuinely full-stack with strong front-end, UX, and customer-facing product experience.
• Hands-on experience shipping production AI-agent features to real users (LLM agents, RAG pipelines, or agent orchestration).
• Comfortable working with React and Python.
• CS undergraduate degree.
• Thrives in ambiguous, fast-moving environments and takes ownership.
• Strong product instincts with ability to turn feedback into shipped code.

Responsibilities

• Diagnose and fix live customer agents, then ship fixes to the orchestration layer the same day.
• Prototype generative UI that adapts in real time to what each prospect cares about.
• Own an eval pipeline: catch quality regressions, trace root causes, roll back, and add tests.
• Design and build net-new infrastructure (e.g. versioning so customers can preview agent changes before they go live).
• Move across the stack as the problem requires, including CSS, migrations, and customer debugging.

Skills

Full-stack

React

Python

UX/product mindset

Ownership

Education

CS undergraduate degree

Job description

davidjoseph-co is hiring a true full-stack founding engineer for a seed-stage startup in San Francisco. You’ll work directly with the technical founder across the conversational AI agent, the embeddable customer-facing experience, the internal platform, the evaluation and self-improvement pipeline, and the underlying infrastructure.

This on-site role offers rapid impact, equity, and broad scope across agents, product, evals, and infrastructure as the first engineers join the team.