Full-Stack Engineer at Darkroom (Brazil)Full-Stack Engineer

We're empowering small teams with technology that makes it easier to market and grow businesses. Our current focus is to help consumer brands shift from "workflow automation" to "agent management" within their marketing operations. Shadow is the AI coordination layer — providing shared AI memory, centralized agent control, and model orchestration for marketing teams.

Why join Shadow?

• Product Ownership You'll ship production code daily and help steer key product and technical decisions.
• Shape the Engineering Culture You'll influence how we work—tools, processes, standards, and hiring.
• Work with Challenger Consumer Brands Talk directly to customers (CEOs, CMOs, VP's) of fast-growing consumer brands—some doing $80M–$500M in revenue.

The agency behind the product Shadow is built alongside Darkroom — a performance marketing agency that's been operating for 10 years, employs 100+ people, runs 100+ clients at a time, and has worked with over 1,000 consumer brands. The agency is both our proving ground and our first user, which means the data you build with is real marketing data at real volume from day one — not a synthetic demo.

This is a fully remote role supporting a team in the EST time zone (9 AM–5 PM EST).

You'll sit squarely at the intersection of back‑end and front‑end, ensuring seamless integration between APIs, databases, UIs, and ML services. You'll design, build, and scale features end‑to‑end, especially our AI/ML‑powered experiences, while mentoring peers and driving architecture decisions.

Core Tech & Tools

• Languages & Frameworks: Python, Node.js, React (TypeScript)
• Datastore: PostgreSQL
• Cloud & Infra: Google Cloud Platform, Airflow, Terraform, Docker, Kubernetes
• ML/AI: LLMs, RAG, prompt engineering

• Architect and implement full‑stack features, from database schema to React components, optimized for scale and reliability.
• Build and maintain RESTful/GraphQL APIs, data pipelines, and distributed services in GCP.
• Integrate, prompt, and debug LLMs and generative AI tools; own RAG or fine‑tuning pipelines.
• Ensure front‑end and back‑end systems interoperate flawlessly, minimize friction, optimize data flow, and enforce contracts.
• Collaborate with product, research, design, and infra teams to define requirements, iterate rapidly, and ship production‑grade code.
• Monitor performance, reliability, and security.
• Mentor junior engineers through code reviews, architecture reviews, and shared best practices.

Must haves

• 5+ years of professional software engineering experience with end‑to‑end ownership in a full‑stack role.
• Deep expertise in Python, Node.js, React/TypeScript, and PostgreSQL.
• Able to be hands‑on with GCP, containerization (Docker/K8s), and building/supporting high‑traffic systems.
• Proven experience integrating AI/ML models (LLMs, NLP, RAG) into production apps.
• Familiarity or strong interest in working with MCP servers.
• Exceptional problem‑solving skills and a product mindset: you think deeply about UX, performance, and business impact.
• You sweat both technical details and end-user experience.

Nice to haves

• Experience with multi‑step or agentic AI workflows.
• Background in AI infrastructure or tooling companies.
• Contributions to open‑source AI/ML projects.

• Unlimited PTO + Local holidays (Relevant to your hub): Rebooting is part of the work. Take the time you need to stay sharp.
• Remote-First Culture: Many roles are fully remote. Employees based in or near our New York or Lisbon HQs are expected to work hybrid with weekly in-office time. Hub locations include Brazil and Spain.
• Parental Leave: Flexible parental leave to support new parents during this important transition.
• Growth: Our interdisciplinary model gives every employee exposure far beyond their core role. Grow your skills, expand your influence, and stay at the forefront of the industry.

We are an equal opportunity workplace—we are dedicated to equal employment opportunities regardless of race, color, ancestry, religion, sex, national orientation, sexual orientation, age, citizenship, marital status, disability, gender identity, or Veteran status. We also consider qualified applicants regardless of criminal histories, consistent with legal requirements.