Full Stack Engineer - Matter

Darkroom•New York, NY

6h•$200,000 - $250,000•Remote

About The Position

We're looking for a Full-Stack Engineer to own the systems that make our AI agents actually work — orchestration, execution, and the APIs that tie everything together. This is equal parts architectural rigor and product intuition. You'll build the backbone of a platform where marketers configure agents, trigger complex workflows, and trust the system to run reliably at scale. You'll report directly to the CEO and work alongside a small team of engineers and designers who ship daily, operate with high autonomy, and aren't afraid to rebuild what isn't working.

Requirements

5+ years of professional software engineering experience with end-to-end ownership in a full-stack role.
Strong hands-on experience with Python and/or Node.js on the backend and React + TypeScript on the frontend.
Deep understanding of front-end state management — how to structure, scope, and evolve state as complexity grows.
Familiarity with patterns like React Query / TanStack Query for server state.
Experience designing and working with relational data models (PostgreSQL).
Comfort operating in a cloud environment (GCP or similar) and deploying containerized services (Docker; Kubernetes familiarity a plus).
Proven experience integrating AI/ML systems into production products — especially LLMs, retrieval-augmented workflows, or agentic systems.
Strong product instincts: you think about UX, performance, and correctness, not just implementation.
Ability to reason about complex systems and make them simpler, more reliable, and easier to work with.

Nice To Haves

Prior experience at an early-stage startup or as a founder.
Background working on AI-powered or data-intensive products.

Responsibilities

Own full-stack features end-to-end — from database models and APIs to frontend integration and UX correctness.
Design and extend backend systems that power complex agent orchestration — subagents, skills, knowledge base retrieval, parallel execution, and long-running workflows.
Build and evolve REST APIs that are stable, well-typed, and easy for the frontend and agents to consume.
Integrate and debug LLM-powered workflows — prompts, tools, retrieval, evaluation loops — with a strong focus on reliability and observability.
Ensure frontend and backend systems interoperate cleanly: tight contracts, predictable data flow, and minimal friction.
Improve performance, resilience, and security across the stack as usage and complexity grow.
Use coding agents (Claude Code, Cursor, etc.) as force multipliers to move faster and push quality higher.
Collaborate closely with product and design to turn ambiguous ideas into shipped, production-grade features.
Raise the technical bar through thoughtful code reviews, architectural discussions, and mentorship of junior engineers.