Thirdlayer
YC W25San Francisco, US · Founded 2025 · 2 employees · Hiring · 6 known investors
Find your way into Thirdlayer
701 people in our graph share verified history with the Thirdlayer team — schools, employers, funds. One of them is your warm intro.
Hemamunlockedknows Regina Lin · together at Stealth Startup (overlapped)
×3knows the team · via Stealth Startup
×4knows the team · via Harvard University
×2knows the team · via OpenAI
knows the team · via Deerfield Academy
knows the team · via Meta
Dex is an AI-powered workspace assistant that ingests operational data across a user's tools and integrations, organizing it into structured context and a knowledge base. It automates tasks, generates insights, and proactively maintains information while users work across their browser and connected applications.
Also known as Dex · Dexterity · Dexterity AI · ThirdLayer
AI & Machine LearningEnterprise SoftwareFuture of WorkSaaSArtificial IntelligenceProductivityConsumer ProductsAIUnited States of AmericaAmerica / Canada
Founders & leadership· Y Combinator alumni (W25)
Thirdlayer was founded in 2025 by Regina Lin and Kevin Gu.
RL
Regina LininFounder/CEORegina Lin is CEO and co-founder of Dex. She studied mathematics and computational science at Harvard, and previously co-founded Contour AI, an LLM evaluation devOps platform, while also contributing to e-commerce marketplace development and working in technology investment roles.
Investors · 6
Theory Ventures✓ verifiedSan Francisco · $1M – $40M
Y CombinatorSan Francisco · $500K
A16Z SpeedrunreportedSan Francisco · $1M
Concept Venturesreported · 2 sourcesLondon · $1.5M
Notion Capitalreported · 2 sourcesLondon · $1M – $100M
Also in the syndicate · 1
Andreessen Horowitz's Speedrun programme
Funding
SEC filings, press & company announcements$5.3M disclosed across 1 of 2 rounds · 2025–2026
- $5.3Mseed roundApr 2026 · 5 sources
Notion Capital (lead), a16z Speedrun, Andreessen Horowitz's Speedrun programme, Concept Ventures
Source ↗ - Undisclosed amountPre-SeedApr 2025Source ↗
Source: company announcements and press reports — follow each round's link for the claim.
Competitors · 5
by search overlap
Dex45 shared keywordsDex is a relationship management tool that provides an intuitive, modern rolodex for organizing and maintaining personal and professional contacts. It eliminates manual data entry and tedious processes, designed as a lightweight alternative to spreadsheets and sales CRMs.
Dex33 shared keywordsDex is an AI-powered recruiting platform that matches software engineers with relevant job opportunities through curated role recommendations and direct access to hiring teams, eliminating traditional application processes. The platform leverages AI to provide candidate-company matching at scale for technology companies.
Nexthink18 shared keywordsNexthink is a software company that provides IT departments with real-time analytics, automations, and employee feedback tools to improve digital workplace experiences. Its platform serves enterprise IT teams managing digital employee experience.
CoinGecko16 shared keywordsCoinGecko is the world's largest independent cryptocurrency data aggregator, providing comprehensive market data including price, volume, and market capitalization across thousands of cryptoassets. It serves millions of users globally with tools, research, and APIs for cryptocurrency market analysis and insights.
DEX Imaging12 shared keywordsDEX Imaging is the nation's largest independent copier and imaging equipment dealer, providing sales and service solutions to businesses.
Companies competing with Thirdlayer for the same Google search keywords, organic and paid, via search-intersection analysis.
In the news
Frequently asked questions
- What does Thirdlayer do?
- Dex is an AI-powered workspace assistant that ingests operational data across a user's tools and integrations, organizing it into structured context and a knowledge base. It automates tasks, generates insights, and proactively maintains information while users work across their browser and connected applications.
- Who founded Thirdlayer?
- Thirdlayer was founded by Regina Lin, Kevin Gu in 2025.
- Who are Thirdlayer's investors?
- Thirdlayer's investors include Theory Ventures, Y Combinator, A16Z Speedrun, Concept Ventures, Notion Capital.
- How much funding has Thirdlayer raised?
- Thirdlayer has disclosed $5.3M raised across 1 of its 2 known rounds.
- Where is Thirdlayer headquartered?
- Thirdlayer is headquartered in San Francisco, US.