Applied AI Engineer -- Contrario

Job Description

Job Information

Applied AI Engineer

Company: Contrario

Job Details

• Location: San Francisco, CA (Onsite)
• Compensation: $150,000 – $239,997 base + 0.2% – 0.6% equity
• Employment Type: Full-Time
• Visa Sponsorship: H-1B, O-1, OPT supported

Role Overview

Contrario is a YC-backed AI startup scaling a marketplace platform. This is an early core engineering role focused on difficult AI product problems rather than CRUD work. The engineer will work directly with the CTO to build production AI systems, taking ownership over technical direction, product architecture, and execution speed.

Machine Learning & Artificial Intelligence

Key focus areas include marketplace intelligence, ranking systems, retrieval infrastructure, recruiter routing, and automation workflows.

Key Responsibilities

• Design and implement intelligent search, retrieval, and recommendation systems.
• Build ML-driven ranking and retrieval systems using embeddings and behavioral data.
• Ship full-stack production features end-to-end.
• Develop AI-native automation workflows for sourcing and evaluation.
• Own core infrastructure including recruiter routing and candidate evaluation pipelines.
• Partner with the CTO on architecture and product evolution.

Technical Stack

• Frontend: React, TypeScript, Tailwind CSS
• Backend: NestJS, TypeScript
• Database: AWS RDS (Postgres)
• Infrastructure: AWS ECS, AWS Fargate
• AI/Data: LLMs, embeddings, vector search, retrieval pipelines, AI automation systems

Requirements

• 3+ years of meaningful AI or ML systems experience.
• Strong proficiency in TypeScript and Python.
• Hands-on production experience with LLMs, vector databases, and AI workflows.
• Experience designing APIs and working with relational databases (Postgres preferred).
• High ownership mindset and ability to operate in ambiguous startup environments.
• Product-minded engineering mentality with strong UX instincts.

Nice to Have

• Experience building search, recommendation, or retrieval systems.
• Marketplace product experience.
• Production LLM product feature ownership.
• Background from LangChain, Palantir, ByteDance, Stripe, or startup founding/CTO roles.

Benefits

• Healthcare (medical, dental, vision)
• Real equity ownership
• Gym membership / wellness stipend
• Flexible PTO
• Free lunches, dinners, snacks, and drinks
• Annual offsites

Interview Process

• Chat with CTO
• Technical interview
• Take-home project
• Chat with CEO
• Work trial (onsite)
• Offer

Important Logistics

Note: This role is fully onsite in San Francisco. Shortlisted candidates will be contacted by David Joseph & Co.

Machine Learning & Artificial Intelligence