Principal Engineer — DevX & AI

You will take architectural ownership of the agent-readable Shop Builder platform as the most senior individual contributor on the DevX and AI team. You will define how developers and AI agents interact with Shop Builder's foundational capabilities, including UI as Data, custom blocks, themes, data binding, catalog, and payments. You will be the technical authority on what the platform exposes and how, staying deeply hands-on with the hardest parts of the work while your decisions bind the platform for years to come.

Responsibilities

• Own the technical architecture of the agent-readable Shop Builder platform: which APIs to expose, in what shape, through which surfaces (REST, SDK, MCP, CLI)
• Define the interface contracts that LLMs and developers interact with — React component APIs, custom block schemas, theme tokens, data binding formats — and maintain them with the rigor of a public API
• Design and lead delivery of the MCP server that allows AI agents to build, deploy, and operate Shop Builder storefronts end-to-end without the editor in the loop
• Architect the CLI and local development environment: how developers scaffold projects, iterate locally, preview changes, and push to production
• Define the deploy, versioning, and rollback model for developer-published content — custom blocks, themes, and layouts
• Design the sandbox and preview environment system so agents and developers can iterate without touching live partner sites
• Set the documentation standard: written for LLMs and humans as first-class users, maintained from single canonical sources and published to every surface
• Lead the eval harness architecture: how the team measures whether an LLM-generated block, theme, or layout is correct before it ships
• Collaborate with Principal/Staff Engineers across payments, auth, live ops, and catalog to pull inbound capabilities into coherent developer-facing surfaces
• Serve as the technical bar-raiser for the team: define code standards, review critical implementation decisions, and mentor the Tech Lead and engineers
• Contribute to hiring and define the technical culture of the team from day one

Requirements

• 10+ years of professional engineering experience, with a demonstrated track record as a Staff or Principal engineer who has shaped platforms, APIs, or developer tooling used by external builders
• Deep expertise in designing and shipping public APIs and SDKs, including versioning strategy, backwards compatibility, and developer ergonomics
• Expert-level proficiency in JavaScript/TypeScript and React
• Hands-on experience building CLI tooling and local developer workflows (scaffolding, hot reload, file-based config, deploy commands)
• Solid understanding of the Model Context Protocol (MCP) or equivalent agentic tool-use interfaces, and practical experience building tools that AI agents can reliably invoke
• Experience building systems at global scale on cloud infrastructure (AWS or GCP), with deep knowledge of containerization, CI/CD, and infrastructure-as-code
• Ability to write and reason about LLM-friendly documentation and API surfaces
• Exceptional technical communication: clear RFCs and ADRs, productive architecture reviews
• Comfort operating in a greenfield context

Benefits

• Medical, dental, and vision insurance
• PTO
• Personalized career roadmap
• Professional development through training and educational opportunities