Founding Full Stack Engineer

Permanent
Technology
Experienced
software engineer, fullstack engineer, type script, python, java script
San Francisco, California
California
Negotiable

Founding Full Stack Engineer - AI Agent for Salespeople

Location: Onsite in San Francisco, CA

Salary Range: $120,000 - $150,000

Stage: Pre-Seed | Y Combinator-backed ($1.5M raised)

About the Opportunity

A stealth-mode startup is building an AI-powered sales agent designed to revolutionize the way sales teams operate. Recently backed by Y Combinator and in its early stages, the company has secured $1.5M in pre-seed funding and is now seeking a Founding Full Stack Engineer to help shape the product and technology vision.

This is a high-impact role where you'll work directly with the technical founding team to build and iterate on the product. With an early version already in use by customers, the team needs a highly autonomous engineer to drive development, implement customer feedback, and help scale the platform.

The Role:

As the Founding Full Stack Engineer, you will:

  • Own end-to-end development of key features, working across the front-end (Next.js) and back-end (Python/FastAPI).
  • Enhance the AI-powered sales agent, integrating Large Language Models (LLMs) to improve functionality.
  • Collaborate with the founding team to prioritize and build features that deliver real value to customers.
  • Balance speed and quality, shipping fast while maintaining a solid foundation.
  • Take ownership of technical decisions, architecture, and scalability.
  • Work closely with customers, gathering feedback and iterating on product development.
  • Grow into a technical leadership role, leading and mentoring future engineers as the company scales.

Ideal Candidate

We're looking for someone who:

  • Has strong full-stack development experience (4+ years preferred).
  • Is proficient in Next.js (React) for front-end and Python (FastAPI) for back-end.
  • Has experience working with LLMs or is eager to learn.
  • Thrives in a fast-paced startup environment, with a high degree of ownership and autonomy.
  • Understands the zero-to-one journey and enjoys building from scratch.
  • Is customer-focused, willing to engage directly with users to understand their needs.
  • Has a passion for AI, sales tech, or productivity tools.

Bonus Points for:

  • Previous experience as a founding engineer or early-stage startup hire.
  • Exposure to B2B sales tools and CRM integrations.
  • Interest in leading and growing an engineering team.

Why Join?

  • Work directly with a YC-backed founding team and be part of a high-growth startup from the ground up.
  • in a company that is solving a real problem.
  • Build and shape the core product that will define the future of AI-driven sales.
  • Tight feedback loop with customers, ensuring fast iteration and impactful development.
  • Be the technical backbone of a startup poised for rapid scaling.

Encouraging Diverse Applications

We welcome candidates from all backgrounds, including underrepresented groups in tech. If you're excited about building AI-powered tools for sales and working in a dynamic, high-impact environment, we'd love to hear from you!

Interested? Apply now and be part of the journey!

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