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22-year-old co-founder and CTO of AfterQuery. Owns the software that validates and filters expert data and the internal training pipeline the company uses to prove quality to labs.

medium confidenceSan Francisco Bay AreaAt AfterQuery since 2025Updated 2026-09-19

Background

Met Spencer Mateega at a Google-run CS summer program in high school. Studied computer science at the University of British Columbia and dropped out (per Forbes). His YC bio lists two internships at Citadel Securities plus software-engineering internships at Meta and Google, and says he previously founded an ed-tech company that was acquired.

What they run now

Technical lead: the validation software that keeps data in the 'challenging but learnable' range, internal model training on AfterQuery data, and the RL environment/long-horizon task infrastructure.

Career

  1. 2025 – presentCo-founder & CTO, AfterQuery
  2. —Software engineering intern (2x), Citadel Securities
  3. —Software engineering intern, Meta / Google
  4. —Founder, Ed-tech startup (name not found) — Acquired, per YC bio
  5. —University of British Columbia, BS Computer Science (YC bio) — Forbes reports he dropped out

On the record

Build-in-public quality · 2026-04

Company line (shared with CEO) that quality must be demonstrated by training models on the data before delivery; no individual public statements on data found. source

Recent posts

3 posts archived · most engaged first, then the latest

Carlos Georgescu
Co-Founder, CTO at AfterQuery
•
AfterQuery just raised our Series A. $30M at $300M valuation to be the software-first data provider for all the foundational labs. Our founding engineering team comes from DoorDash, Palantir, Amazon, LinkedIn, and Bloomberg — and we maintain a very high hiring bar. We’re hiring exceptional engineers.
14938 comments • 6 reposts
Carlos Georgescu@CarlosGeorgescu·
AfterQuery just raised our Series A. $30M at $300M valuation to be the software-first data provider for all the foundational labs. Our founding engineering team comes from DoorDash, Palantir, Amazon, LinkedIn, and Bloomberg. We’re hiring exceptional engineers!
85788.9KView on X ↗
All 3 in the feed →

Connections

Who they amplify

Accounts whose posts Carlos has reposted recently: Altos Ventures, Forbes, AfterQuery.

Why it matters here

If AfterQuery ever builds design/visual-judgement pipelines (tooling for pairwise rating, rubric scoring, rater QA), he owns them. Little direct public output on taste data.

How to reach

Speculative: technical, low public profile; reach via X or through Mateega. Relevant ask: how they measure rater reliability for subjective (design) judgments.

What we could not establish
  • Name of his acquired ed-tech company
  • Conflict between YC 'B.S.' and Forbes 'dropped out'
  • No interviews or talks found

Sources

  1. Y Combinator company page: AfterQuery
  2. Forbes: This 23-year-old's new AI data company has already hit a $100M run rate (2026-04-09)
  3. Forbes: AfterQuery becomes YC's fastest unicorn at $3.2B (2026-09-01)
  4. Forbes Technology Council: Carlos Georgescu
Also at AfterQuery
high confidence

Spencer Mateega

Co-founder & CEO

low confidence

Danny Tang

Co-founder