Karumi

24/7 AI demo agent for B2B SaaS

Product Engineer (Full-Stack)

$100 - $1700.20% - 2.00%San Francisco, CA, US / New York, NY, US
Job type
Full-time
Role
Engineering, Full stack
Experience
3+ years
Visa
Will sponsor
Skills
Python, React
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Toni Lopez
Toni Lopez
Founder

About the role

The Opportunity

Join our product engineering team in the US to build features that directly impact how customers experience and adopt our platform. This role bridges technical execution and product thinking - you'll ship user-facing features while making architectural decisions across the entire stack.

You'll work end-to-end: designing interfaces, building APIs, optimizing performance, and deploying to production. We move fast, iterate with users, and expect engineers to own problems from concept to launch.

We sponsor visas for qualified candidates.

Core Responsibilities

- Build full-stack features from UI components to backend services

- Design and implement responsive, intuitive user interfaces with React

- Develop high-performance APIs using FastAPI and async Python

- Work with LLM integrations, prompt engineering, and AI-powered workflows

- Deploy and monitor features across our AWS infrastructure

- Gather user feedback and iterate rapidly on what you ship

Technical Requirements

- Strong full-stack development experience (frontend + backend)

- Proficient in React and modern JavaScript/TypeScript

- Python skills with FastAPI or similar frameworks

- Experience with PostgreSQL, Redis, and async patterns

- Comfortable with AWS/Azure/GCP, deployment pipelines, and infrastructure basics

- Product mindset - you care about user experience and customers, not just code

Nice to Have

- Experience building with LLMs and AI-powered features

- Browser automation or headless browser technologies

- Design sensibility and attention to UI/UX details

- Previous startup or 0-to-1 product experience

Why Karumi

- Meaningful equity stake in a backed, fast-growing company\

  • End-to-end ownership of features users interact with daily\
  • Direct impact on product direction and company trajectory\
  • Small team where shipping matters more than process\
  • Gym\
  • Visa sponsorship available

About Karumi

Karumi lets SaaS companies deliver personalized product demos at scale, 24/7, in any language. Our AI agent learns from any software product, joins video calls with prospects, and navigates the product in a real browser while talking, listening, and taking actions. By delivering the “aha moment” instantly, Karumi eliminates demo waiting times and boosts conversion.

Karumi
Founded:2025
Batch:F25
Team Size:2
Status:
Active
Founders
Toni Lopez
Toni Lopez
Founder
Pablo Omenaca
Pablo Omenaca
Founder