Head of Finance

About Us

Sieve is a multi-modal lab curating the world's highest-quality training datasets — spanning video, audio, images, text, and 3D. We combine exabyte-scale data infrastructure and novel multimodal understanding techniques that push the frontier of foundation models. Video alone makes up 80% of internet traffic, and across modalities, data has become the enabling medium powering creativity, communication, gaming, AR/VR, and robotics. Sieve exists to solve the biggest bottleneck in the growth of these applications: high-quality training data.

We partner with top AI labs and did $XXM last quarter alone, as a team of ~30 people. We also raised our Series A from Tier 1 firms such as Matrix Partners , Swift Ventures , Y Combinator , and AI Grant .

Why Now

Sieve is one of the most capital-efficient teams in AI — roughly 30 people serving the world's leading AI labs across every major data modality. You'll join early, own problems end-to-end, and watch your work ship directly into the models defining the frontier.

About the Role

You’ll be Sieve’s first finance leader, owning the financial foundation for our next stage of growth and helping build the finance function from scratch.

This role will own financial planning, infrastructure, and reporting while developing a detailed understanding of Sieve’s unit economics. You’ll help make better decisions across customer deals, compute commitments, contributor payouts, hiring, and capital allocation.

You’ll be equally comfortable building detailed models, working across messy operational datasets, and turning your analysis into clear recommendations.

What You’ll Do

Build and own Sieve’s financial model, forecasts, budgets, and runway planning

Model the true cost and margin of customer deals across reinforcement learning, computer use, video, and other data types

Partner with leadership on pricing, resource allocation, hiring plans, compute strategy, and other strategic decisions

Model and optimize contributor payouts to balance supply, quality, speed, and margin

Own financial reporting for the leadership team and board

Work across commercial, engineering, and operations teams to improve financial visibility and operating efficiency

Own treasury, monthly close, payroll, tax while helping build the finance team

Requirements

6+ years of experience in strategic finance, FP&A, investment banking, private equity, or a similarly analytical role

Strong financial modeling skills and a rigorous understanding of unit economics, contribution margin, and cash flow

Built up a tech finance function before, or at least major parts of one, from scratch.

Comfortable operating with significant ownership and ambiguity in a fast-moving startup

Excellent communication skills and experience partnering with senior leadership

Experience working with a modern finance stack + AI tooling

In-person at our SF HQ

Nice to Have

Experience at an AI, infrastructure, data, marketplace, or usage-based software company

Experience modeling compute, storage, or other variable infrastructure costs

Experience as an early finance hire at a startup and built teams from scratch

Benefits

401k + Full Health Insurance

Breakfast, Lunch, and Dinner covered and your choice of snacks

Ubers covered home