Underdog Launches as Private AI Assistant

From Hacker House to Thiel Fellow

When self-taught coder Sigil Wen was 17, he moved to Silicon Valley and lived in an AI hacker house with famed AI researcher Andrej Karpathy. While there, he hacked and coded alongside other people who would become the biggest names in artificial intelligence, like Perplexity founder Aravind Srinivas and OpenAI researcher Noam Brown. He tested early versions of AI tools that would later become well known, including a chatbot shared by Anthropic co-founder Ben Mann that would become Claude, an image generator from David Holz that would become Midjourney, and what would become OpenAI’s GPT-3 and the image generator Stable Diffusion. Prominent investor and entrepreneur Naval Ravikant hired him for Airchat, Ravikant’s now-defunct rival to the Clubhouse social network. For fun, he figured out how to get GPT-2 running on his Apple Watch, an era he recalled to TechCrunch as a magical time.

Building Husky and On-Device Privacy

Now a Thiel Fellow, the program from investor Peter Thiel that invites young founders to pursue projects instead of college, Wen on Tuesday, Oct. 6, 2026, launched an invite-only beta of Underdog, one of the most private AI assistants Silicon Valley has yet to offer. The model runs wholly on-device, meaning user data remains on devices they already own, currently Macs and Windows PCs, with Linux, iPhone, and Android versions coming soon. Wen built Husky, an inference engine designed to run fast. Unlike other on-device engines, Wen says, it moves less data between the computer’s main chip and its graphics chip. Underdog has other security features baked in, too, like encrypting the keys to the email and other accounts that users authorize Underdog to access. This capability reflects a broader push into Apple's on-device AI push forces a recalibration across Silicon Valley suppliers as more founders attempt to decouple intelligence from the cloud.

Capability and Low-Overhead Economics

Underdog uses much smaller models than today’s state-of-the-art ones hosted in data centers. It currently uses a 27-billion parameter reasoning model fine-tuned from Qwen3.8 27B. Wen argues that this model compares favorably with Claude Opus 4.6 in some benchmarks, or what was considered top performance six months ago. He says that means it can handle the everyday tasks that people want an AI assistant to do, like shopping research or answering math homework questions. Because the AI runs on users’ machines, Underdog does not have the giant overhead of paying a provider for inference, allowing it to remain free at first and never ad-supported. As the ecosystem evolves, many observers continue to debate Silicon Valley’s Legacy vs The New Technology Startups regarding infrastructure costs and deployment models.

Fintech Rails and High-Profile Backers

Instead of a subscription fee, with Stripe co-founder Patrick Collison as one of his angel investors, Wen is borrowing a play from the fintech era. Underdog will take a tiny percentage of payment transactions that the AI assistant makes using Stripe’s secure payment rails, something like an interchange fee. In this way, the AI assistant never has to mine user data. This runs contrary to the business motivations of many other players in AI assistants, whose privacy policies allow them to collect data on users that they may sell to advertisers or third parties, or use to train other models. That data collection could be a treacherous trade-off for users whose assistant needs access to intimate details, from medical conditions to financial data to information on their kids. As Wen wrote in what he calls his AI manifesto, why should using AI require surrendering your private information, telling TechCrunch that he wants to build a product he would be proud for his future children to use.

Conway Research Funding Syndicate

The startup behind Underdog is named Conway Research, and Collison is not its only big-name investor. Conway is backed by Andreessen Horowitz via partner Chris Dixon, as well Khosla Ventures, Hummingbird, SV Angel, the Anthology Fund, which is the partnership fund between Menlo Ventures and Anthropic, and a prominent list of angel investors that includes Vercel founder Guillermo Rauch, Noam Brown, and Deedy Das, among others.