AfterQuery

We teach machines how experts think, applied research lab connecting 100,000+ verified professionals with frontier AI labs.

AI Training AI / Machine Learning 7 following
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San Francisco, CA, USA HQ
11-50 company size
2025 founded

What is AfterQuery?

AfterQuery is a San Francisco applied-research lab founded in January 2025 (Y Combinator W25 batch) by three Wharton/Penn co-founders, Spencer Mateega (CEO), Carlos Georgescu, and Danny Tang. The company curates data solutions that capture expert reasoning and real-world workflows, then converts them into training data for foundation-model labs. Service portfolio: Supervised Fine-Tuning datasets with chain-of-thought reasoning, Reinforcement Learning with expert-designed rubrics, Agent Environments (API/MCP) for real workflows, and Computer Use Trajectories from human demonstrations. Their network spans nearly 100,000 verified practicing professionals across finance, law, medicine, engineering, software, ML/data science, business, and health. AfterQuery raised a $30M Series A at a $300M valuation (April 2026, led by Altos Ventures with The Raine Group, Y Combinator, and BoxGroup) and is reportedly above $100M annual revenue run rate within ~16 months of founding. Sign up to contribute at https://experts.afterquery.com/.

Mission & values

Teach machines how experts think, capture expert reasoning and real-world workflows, then convert them into training data that teaches AI models how professionals actually solve problems.

Qualifications

Two engagement paths exist. (1) AfterQuery Experts (experts.afterquery.com), the contributor program for domain professionals. Active tracks include finance, law, medicine, engineering, software engineering, ML/data science, business, and health. ML/DS expert listings target 1–3 years of experience; PhD is not strictly required but specialist tracks command higher rates. Per public coverage, pay ranges roughly $40–$50/hr for general expert work and up to $200–$250/hr for top-of-skill specialists. (2) Corporate hiring at afterquery.com/careers, 18 open roles, all in San Francisco and mostly onsite (Engineering, Research on Frontier Data and Post-Training, Strategic Projects/Operations, Growth, Sales). For remote-only contributors, the Experts side is the relevant path.

Leadership

S

Spencer Mateega

Co-Founder & CEO

B.S. Finance & Statistics (Wharton) and M.S. Computer Science (Penn). Previously interned at Silver Lake (tech PE), Morgan Stanley (tech IB), Meta, and Google before co-founding AfterQuery in January 2025.

C

Carlos Georgescu

Co-Founder

Met Spencer at a Google high-school summer program; later interned together at Meta. Previously at Citadel Securities (2x), Meta, and Google. Past acquired ed-tech founder.

D

Danny Tang

Co-Founder

Met Spencer in high school where they co-founded and sold a startup. Both attended Wharton as roommates before launching AfterQuery.

Hiring process

  1. 1

    Apply at experts.afterquery.com/apply

    Submit an application listing your domain expertise and credentials.

    About 1 day

  2. 2

    Vetting & domain assessment

    Pass domain-specific tests for the Experts track you target (finance, law, medicine, engineering, SWE, ML/DS, etc.).

    About 5 days

  3. 3

    Onboarding

    Calibration tasks, profile setup, and platform onboarding.

    About 3 days

  4. 4

    Project matching

    Get matched to AI-lab client projects (SFT data, RL rubrics, Agent Environments, Computer Use Trajectories).

    About 5 days

  5. 5

    Get paid

    Per-project payouts processed through the platform.

    About 7 days

Funding

StageSeries A
Investors
Altos Ventures The Raine Group Y Combinator BoxGroup

Awards & recognition

  • $30M Series A at $300M valuation · 2026

    BusinessWire ↗

  • $100M+ annual revenue run rate within ~16 months of founding · 2026

    BusinessWire / FinSMEs

  • Y Combinator Winter 2025 batch · 2025

    Y Combinator ↗

Company information

Frequently asked questions

Who founded AfterQuery?
Three Wharton/Penn co-founders launched AfterQuery in January 2025 as part of Y Combinator W25: Spencer Mateega (CEO, ex-Silver Lake/Morgan Stanley/Meta/Google), Carlos Georgescu (ex-Citadel Securities/Meta/Google), and Danny Tang (ex-Wharton roommates with Spencer; sold a high-school startup together).
What does AfterQuery do?
It captures how experts actually think and work, chain-of-thought reasoning, RL rubrics, agent environments, and computer-use trajectories, then sells that as training data to frontier AI labs.
How big is the expert network?
Nearly 100,000 verified practicing professionals across finance, law, medicine, engineering, software, ML/data science, business, and health.
What can I earn as an Expert?
Public coverage cites $40–$50/hr for general roles and up to $200–$250/hr for top-of-skill specialists. Pay depends on domain, project complexity, and your credentials.
How is AfterQuery funded?
$500K seed from Y Combinator (W25) plus a $30M Series A in April 2026 at a $300M valuation, led by Altos Ventures with The Raine Group, Y Combinator, and BoxGroup. Reportedly above $100M annual revenue run rate.
Who are the customers?
Frontier AI labs and enterprises building foundation models. AfterQuery describes itself as supporting "every leading frontier AI organization."

Stay in the loop.

One email per week, 5 hand-picked roles.