Every question you ask an AI assistant costs the company money. So they bill you a subscription, or mine your data to cover the spread. On Monday, Thiel Fellow Sigil Wen launched an assistant that does neither — because it never touches a server at all.
According to TechCrunch, Wen’s Underdog entered invite-only beta on October 6 as what the outlet called one of the most private AI assistants Silicon Valley has yet offered. The whole thing runs on-device — Macs and Windows PCs for now, with Linux, iPhone, and Android versions coming — so your data never leaves hardware you already own.
The Resume That Doesn’t Exist Anymore
Wen is self-taught. At 17, he moved to Silicon Valley and lived in an AI hacker house with Andrej Karpathy, testing proto-versions of what would become Claude, Midjourney, and GPT-3 — and, for fun, getting GPT-2 to run on his Apple Watch.
His startup, Conway Research, is backed by Andreessen Horowitz via Chris Dixon, Khosla Ventures, the Anthology Fund (Menlo Ventures plus Anthropic), and angels including Stripe co-founder Patrick Collison, Vercel’s Guillermo Rauch, and OpenAI researcher Noam Brown.
Private by Physics, Not by Promise
Every assistant promises privacy. Underdog sidesteps the problem instead of managing it: a cloud assistant must see your data to answer you. If the server never sees it, there is no server breach to fear — that is the entire thesis.
The engine is called Husky, an inference layer Wen built to shuttle less data between a computer’s main chip and its graphics chip than rival on-device engines. The model is a 27-billion-parameter reasoning model fine-tuned from Qwen3.8-27B — far smaller than the data-center giants, but Wen claims it compares favorably with Claude Opus 4.6 on some benchmarks, or what counted as top-tier performance six months ago. His argument: that’s plenty for the shopping research and math homework people actually ask assistants to do.
Underdog also encrypts the keys to the email and other accounts you authorize it to access — meaningful, because an agentic assistant that can read your inbox is only as private as its key storage. Dealroom reports the company claims its engines run up to 4.5 times faster than Apple’s own MLX framework, and that a smaller 4-billion-parameter model called Woof fits under 2.5GB.
The Business Model That Kills the Subscription
Here is the part the launch recaps skim past. Underdog is free and will never be ad-supported — arithmetic, not idealism. Since the AI runs on your machine, Conway pays no provider for inference. “I don’t have to charge you a subscription to run this because my costs are so super low,” Wen told TechCrunch.
Instead, Underdog plans to take a tiny cut of payment transactions the assistant makes on your behalf through Stripe’s secure rails — an interchange-style fee. The assistant gets paid when you buy things, so it never has to sell your attention.
| Assistant | Where your data goes | How you pay |
|---|---|---|
| Underdog (Conway) | Stays on your device | Free; tiny fee on assistant-made payments |
| Hark Pro | The company’s cloud | Free tier, paid plans from $20/month (Fast Company) |
| Cloud giants | Their servers — with policies that let them train models on it or sell it to advertisers | Subscriptions up to $500/month |
Why This Matters
The commodity coverage frames Underdog as a privacy pitch. The real story is structural: it decouples AI assistants from the two business models that made them creepy. Subscriptions exist because inference is expensive. Ads exist because inference is expensive and data is valuable. Put the compute on the user’s own hardware and both pressures evaporate — along with the server-side honeypot that makes assistant breaches so devastating.
One honest caveat: on-device is not a force field. Your laptop can be malware-compromised, and encrypted keys still mean an agent with access to your inbox. But it shifts the threat model from “one breached data center exposes millions of users” to “your own machine is the vault” — a trade millions will take.
Meanwhile in Apps & Tools: TikTok turned your For You feed into a checkout — assistants that shop for you are becoming the default interface. Meanwhile in Apps & Tools: Apple’s HomePad is the first gadget that lives or dies on the new Siri — and it lands October 13.
