Sentient OS YC Application

Fall 2026Active

San Francisco

Sentient OS went through Y Combinator in the Fall 2026 batch as a B2B company. Below: what the company does, who founded it, and its application to YC, reconstructed question by question in the real YC form.

YC batch: Fall 2026
Industry: B2BProductivity
Location: San Francisco
Team size: 2
Status: Active
Launched: 2026

Founders

Jesai TarunFounder/CEO
Aditya VellankiFounder/CTO

What Sentient OS does

Nobody's built truly proactive AI, because it requires running inference on your entire life. In the cloud, that's insanely expensive and a privacy nightmare. But not on your own chip. Every night, Sentient's on-device LLM wakes your Mac and understands what's new in your life (email, messages, files, Granola transcripts...), entirely locally, and distills it into a knowledge base. You wake up to your work already prepared: the reply you forgot, drafted from your own context; the subscription you never use renewing tomorrow, caught; the report you promised in the group chat, ready to send. Everything is one click from firing through computer use, and nothing fires until you click. Or click your Mac notch anytime and say "finish this for me." Sidekick takes over the thing you were doing with its own cursor while you move on. On-device inference at this scale was supposed to be impossible: devices too slow, and models too dumb. So we built the stack ourselves: a custom LiteRT-LM fork (KV-cache reuse, speculative decoding, custom k-quants) that runs nightly on 8 GB Macs. The user's hardware does ~90% of the compute, and their own ChatGPT or Claude subscription does the rest, so our marginal cost is ~$0, and our servers store nothing. We soft-launched late July with one Reddit post: top of r/macapps, 2,000+ users in 48 hours, $0 marketing. Free and open source for consumers; the same engine on the work stack (Slack, Granola, Linear, Notion) becomes the enterprise business.

Sentient OS's YC application, reconstructed

Y Combinator application

Sentient OS, Fall 2026 batch. The real form questions, answered from public data.

Founders2
Company7
Progress7
Idea4
Equity3
Curious2
Batch Preference1

Company

Company name

Sentient OS

Describe what your company does in 50 characters or less.

On-device AI does your work overnight.

What is your company going to make? Please describe your product and what it does or will do.

We're building Sentient, an on-device LLM that processes all your personal and work data (email, files, messages, work apps) locally on your Mac each night. In the morning, you have prep work already done: drafted replies, caught subscriptions, prepared reports, one-click from completion - but nothing is sent until you approve. There's also a real-time command UI: click your Mac notch anytime, say 'finish this for me,' and Sidekick takes over the task using your own context. All inference runs mostly on the user's Mac, keeping privacy and marginal costs low. We ship a custom LiteRT-LM fork, optimized to do this on 8GB Macs.

Where do you live now, and where would the company be based after YC?

San Francisco, CA, USA. We would stay based in San Francisco after YC.

Explain your decision regarding location.

San Francisco is where the best AI and productivity startups are, and it's easier to find users and technically-minded companies to partner with here.

21 more answers in the full application

Founders, Progress, Idea, Equity, Curious, Batch Preference are in the full version. Create a free account to open it in YC Insights, next to every other YC batch.

See full application

Frequently Asked Questions

Is this the real Sentient OS YC application?

No. Y Combinator keeps submitted applications private. This is a reconstruction: the real YC form questions, answered from Sentient OS's public data (launch notes, founder backgrounds, product description). It shows how a company like Sentient OS would present itself to YC, not the text they submitted.