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The project

An assistant where nothing you say leaves the phone. Not a privacy policy, but an architecture in which there is no server to send anything to.

The distinction matters. A privacy policy is a promise the reader is asked to believe. An architecture with no server is a constraint: the promise holds even if nobody trusts the person making it.

That constraint decides the rest of the build. Our own packages ship inside the app rather than being fetched at runtime, and the weights are not shipped at all: the app pulls them from Hugging Face on first run, our in-house models alongside Qwen. That download is the only thing that crosses the network, and it carries no conversation with it.

What it took

Expo SDK 57 and React Native on the New Architecture. Models running on-device through llama.cpp. A model download manager: the app ships with no weights at all.

A mode system, including a parent-gated kid-safe mode. And retrieval that runs on the device, over a hand-picked wellbeing library.

The Challenge

Proving the claim instead of asserting it.

The product and the website load no third-party requests and set no cookies. The site ships a file listing every claim and where it came from, and it has no build step. A sceptic can check the argument on the very page making it: open the network inspector and watch nothing happen.

Everything else has to fit inside that constraint. The models are fine-tuned in house, retrieval runs over a library held on the device, memory persists between conversations without leaving it, and the modes switch behaviour locally. None of it can be offloaded, because there is no bigger machine to fall back on: every feature is designed around what a phone can actually hold and run.

Where it stands

617 tests green as of 23 August 2026. The Android build has shipped, iOS is in progress.