Platform Engineer — AI Infra Specialist

SupportFinity™; San Francisco (CA); On-site; USD 180,000 - 260,000; Full time

Job summary

Poly is building a groundbreaking file storage platform with a multimodal AI. We are expanding from a small founding team to a larger group and seek a platform engineer (AI infra specialist) to help scale the cloud architecture and AI systems, enabling fast, reliable file storage and intelligent search capabilities.

You will work in-person in SoMa, San Francisco, shaping infrastructure, collaborating across disciplines, and driving platform excellence in a fast-paced startup environment.

Qualifications

• Core AI principles and fundamentals around training, inference, loss, gradient descent, embeddings, tokenization.
• Experience with modeling / inference tools such as PyTorch and CUDA.
• Ability to build data pipelines for loading and transforming data with high throughput.
• Familiarity with prompting, function calling, and agentic workflows in LLM-based development.
• Knowledge of Python is a must; enthusiasm for Rust is encouraged.

Responsibilities

• Shape cloud architecture to store files at breathtaking speed and scale.
• Improve our AI architecture to become the 'search engine for your life'.
• Bring Poly to life as a robust platform through hands-on platform engineering.

Skills

Core AI principles

PyTorch

CUDA

Data pipelines

LLM fundamentals

Python

Rust

Learning mindset

Collaboration across domains

On-site in SoMa SF

Job description

About Us

Poly is building a better file storage platform for everyone. We've raised $8M from YC, Bloomberg Beta, Felicis, Figma Ventures, AI Grant, and more, and we're looking to grow our founding team of superstar builders and dreamers.

Poly’s intelligent file system is a desktop and web application that lets you store and browse your files with the help of a powerful multimodal AI. An easy way to wrap your head around it is to check out a demo from Abhay

• Our product is intelligent -- all your files are indexed and searchable with an AI that can find and even sort and organize your files, search by image and many other file types, and soon ask questions about your files and watch as an AI system references your own files to give an answer.
• We’re maximally multimodal. We support any audio, video, document, office file, slide deck, text file, PDF, and a whole lot more. We even support saving web links and youtube videos to your Poly file system and asking the AI about them.
• We’re completely, 100% cross-platform -- Our product looks identical across web and desktop, with zero compromises in the UI/UX, and all your files always available and up-to‑date.
• Our product improves every 2 days, not every 2 years -- Finder and File Explorer haven't changed in years or decades because they're linked to OS upgrade cycles. Our product ships updates every day and can add all kinds of features, fixes, and file type support at light speed.
• Many, many more reasons -- deep folder searching, beautiful view modes, extensible metadata, ergonomics, public sharing, and so much more.

About You

We are looking to grow from a team of three (we've accomplished a lot as just two engineers and one designer!) to a clan of around eight, so you'll be anywhere from engineer #3 to #7. You'll be tasked with bringing Poly to life as a robust platform, shaping our cloud architecture to store files at breathtaking speed and scale, and improving our AI architecture to become the "search engine for your life".

Specifically, in a platform engineer (AI infra specialist) role, we are looking for the following concrete skills and prior experience

• Core AI principles and fundamentals around training, inference, loss, gradient descent, embeddings, tokenization and a strong baseline in multivariate statistics
• Extensive experience with modeling / inference tools such as pytorch and CUDA.
• Ability to build data pipelines for loading and transforming data with high throughput to a training or inference platform.
• Familiarity with modern LLM-based development fundamentals including prompting, function calling, and agentic workflows.
• Knowledge of Python is a must, and enthusiasm for Rust is highly encouraged.
• An extreme appetite for learning that you've honed through recursive self-improvement. You should be able to demonstrate an exceptional aptitude for automating your own development processes.
• You thrive in independent, inter-disciplinary environments, and you are skilled at collaborating across domains and for productively engaging with people of all kinds.
• You are willing to leave judgments about gender, race, creed, background, belief, or politics for outside of the workplace so that we can focus on building the world's best file storage platform for everyone.
• You are capable of (and excited to) work in-person 5-days a week in SoMa, San Francisco

About the company

Poly