Full-Stack Engineer

OpenKrill; United States; Remote; USD 140,000 - 210,000; Full time

Benefits offered by this job

Unlimited PTO

Remote-first culture

Parental leave

Growth opportunities

Job summary

Openkrill is seeking a seasoned software engineer to join Shadow, our AI coordination layer, working at the intersection of backend services, front-end interfaces, and ML tooling. You will design, build, and scale features, integrate APIs and data pipelines, and mentor peers.

This fully remote role follows EST business hours and supports a fast-growing consumer-brand client base. You'll work with Python, Node.js, React/TypeScript, PostgreSQL, GCP and container tech to deliver production-grade

Qualifications

• 5+ years of professional software engineering with end-to-end ownership.
• Expertise in Python, Node.js, React/TypeScript, and PostgreSQL.
• Hands-on with GCP, Docker/Kubernetes, and high-traffic systems.
• Experience integrating AI/ML models into production apps.
• Familiarity with MCP servers or interest in it is a plus.
• Strong product mindset with focus on UX, performance, and impact.
• Ability to mentor peers and contribute to architecture decisions.

Responsibilities

• Architect and implement full-stack features from database to UI, scalable and reliable.
• Build and maintain RESTful/GraphQL APIs, data pipelines, and distributed services in GCP.
• Integrate, prompt, and debug LLMs and AI tools; manage RAG/fine-tuning pipelines.
• Ensure seamless interoperation of front-end and back-end systems and contract enforcement.
• Collaborate with product, research, design, and infra teams to shape requirements and ship code.
• Monitor performance, reliability, and security across systems.
• Mentor junior engineers through code reviews and architecture discussions.

Skills

Full-stack engineering

Python

Node.js

React/TypeScript

PostgreSQL

Google Cloud Platform

Docker

Kubernetes

AI/ML integration

Problem solving

Tools

PostgreSQL

Google Cloud Platform

Airflow

Terraform

Job description

WHAT WE'RE BUILDING

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).

THE ROLE

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

WHAT YOU'LL OWN

• 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.

WHAT WE OFFER

• 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.

EQUAL OPPORTUNITY STATEMENT

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.