Underdog AI: On-Device, Privacy-First Assistant Launches
Original: Silicon Valley’s AI wunderkind launches Underdog, the most private Instinct/Muse competitor yet
Why This Matters
On-device AI with no subscription could pressure cloud-based assistant pricing models.
Thiel Fellow Sigil Wen launched Underdog, an invite-only AI assistant running entirely on-device on Macs and Windows PCs, powered by a 27B-parameter Qwen3.8-27B fine-tune, with no cloud inference costs and no subscription fees.
Sigil Wen, a self-taught coder and Thiel Fellow with an unusually connected AI origin story—he shared a hacker house with Andrej Karpathy, Aravind Srinivas, and Noam Brown, and tested early builds of what became Claude, Midjourney, and GPT-3—has launched Underdog, an on-device AI assistant now in invite-only beta.
The app runs entirely on users' own Macs and Windows PCs, keeping data off the cloud. It's powered by Husky, Wen's proprietary inference engine that he claims moves less data between CPU and GPU than rival on-device engines. Security features include encrypted keys for any email or external accounts users connect. Linux, iPhone, and Android support are planned.
Underdog currently runs a 27-billion parameter reasoning model fine-tuned from Qwen3.8-27B. Wen claims it matches Claude Opus 4.6 on some benchmarks—performance he frames as "top-tier from six months ago"—sufficient for everyday tasks like research and homework. Because inference runs locally, Wen says his operational costs are low enough to offer the app free with no ads and no subscription, at least initially.