Head of AI (a16z sr)

Sourcerer

Sourcerer

Software Engineering, Data Science

San Francisco, CA, USA

Posted on Apr 28, 2026

Sourcerer builds AI agents that autonomously source and negotiate across B2B marketplaces — navigating platforms via browser automation, conducting multi-turn negotiations, and extracting structured quotes. Our mission is to transform how businesses procure goods by automating complex sourcing workflows end-to-end.

Role Overview

The Head of AI will own the intelligence layer of our platform and build the team that scales it. This role is strategic and hands-on, focused on designing robust AI systems that operate autonomously in real-world environments.

Key Responsibilities

AI Orchestration Design and optimize across multiple LLM providers, each serving different roles (conversation, reasoning, media processing)

Negotiation Engine Own the AI pipeline driving autonomous supplier conversations, including message generation, conversation assessment, and response routing

Prompt Engineering Design structured prompt systems across platforms for negotiation, supplier evaluation, and contact enrichment

Platform Expansion Extend AI capabilities to new B2B marketplaces and messaging channels

Reliability & Evaluation Build testing frameworks and evaluation practices for non-deterministic AI outputs

Team Leadership Hire, mentor, and manage a high-performing engineering team as the company scales

Minimum Qualifications

4+ years in software engineering, with 2+ years building production LLM applications (autonomous systems, not prototypes)

Hands-on experience with multiple LLM APIs (structured outputs, tool use, cost optimization)

Strong Python skills, including FastAPI, async programming, and Pydantic

Experience with browser automation (Playwright or Puppeteer) at scale

Background in early-stage startups or high-ownership environments

Proven experience hiring and managing engineers

Strong communication skills with the ability to translate AI capabilities into product decisions