A local-first desktop companion. Your model key, your machine, your file — the conversation never routes through us.
No repo to clone, no build step, no coding agent standing over your shoulder. You run the installer, you paste your key once, and it is yours — out of your own file, on your own machine.
A desktop app for Windows. You install it, you paste in your own model key one time, and it is yours from then on — the chat, the memory, the journal, the creations and the key itself all live on your machine. The key goes into Windows Credential Manager, and the app can replace or delete it but cannot read it back. Nothing you say is stored on our side, because there is no our side: the app talks to your provider directly.
Anthropic, OpenAI, xAI, Gemini, OpenRouter, DeepSeek and Groq, plus a Local door for any OpenAI-compatible endpoint you run yourself — model and base URL are yours to type. Type any model ID by hand, or fetch that door's live list with your own key. A hosted door's key is pinned to that door's own address and cannot be sent to any other host.
Or open it with no key at all — the Offline demo runs the room, the memory and the safety floor entirely on your machine.
Memory is checked locally after each exchange, with no second model call — your own words, kept as you said them, never a paraphrase.
When it has nothing stored it says it does not remember, rather than filling the gap. Every turn shows you how many memories were served and how many were saved, so you watch it work.
Anything shaped like an API key, a password, a PIN, a card or a seed phrase is refused before it can ever be remembered. And every session checks the file before it writes — a corrupt database is set aside intact and named, with three rotating snapshots beside it.
Pin up to twenty things it must never forget and they ride every single turn. Read the whole store as a .md, back it up as .json, restore it — a truncated or miscounted archive is refused whole instead of half-restored, and a restore only ever adds.
Delete a memory and it goes — the row, its search index, the linked turns, the summary and the scrubbed database pages, with the app telling you plainly what it cannot reach.
The Mind graph draws what it kept as an offline constellation — a view of your own file, not another model call. Daily tending — the one optional review pass a day, which can cost up to three provider requests — ships off.
Entries your companion writes in its own voice, drawing only on memories saved on this machine. Written while the app is open — nothing runs in the background. Inner life defaults to off on any door that costs you money.
Remove any entry from the local store. Asking for one yourself is never rationed — the daily allowance governs only what it starts on its own, so a manual "write one now" is a provider request you chose to spend.
Self-contained HTML and CSS pieces — a morning card, a small constellation. Scripts, embedded frames and outside links are stripped before saving, then shown in a sandboxed frame that cannot reach the network.
That one is tested, not asserted: a browser test stands up a real listener, renders a hostile creation with eight different ways out, and counts zero. Export any creation as a standalone .html file, or delete it.
Replies read aloud in your computer's own system voices, with speed and voice pickers. Microphone audio is held in memory, transcribed locally with Whisper, and never sent to a speech cloud. Hands-free listening and Screen Share ride on the floating familiar that installs alongside the app — the little body on your desktop is part of the install, not an extra.
Compiled application constants are layered after whatever profile you import, so an imported identity cannot replace them. The crisis line sits under every conversation — today it names 988 and North American emergency services, so buyers elsewhere should treat it as a pointer to their own local line.
Every install comes with its own familiar — a small animated body that lives on your desktop, with a room palette that colours the whole app. Six ship in the box; pick yours on install day. Nothing extra to buy.
Tested on: our own Windows 10/11 desktops and laptops, a two-year-old office PC, and the oldest CPU we support (SSE3-only, receipt collected September 3, 2026). Phone pairing is in beta. All sales are final: once it is downloaded, it is yours. Support terms are in the package.
Work out of a terminal instead? The Memory Kit — MCP Edition is a separate product and it lives in the code shop — bundle it with the app for $249, or take it on its own →
Ten real screens of the app, captured from the release build. The companion in these shots is a demo profile called Vesper.
The pairing fields visible in the last shot belong to the iPhone lane, which is still coming — see the note above.
Some people want the thing installed and working before dinner, by someone who has done it a hundred times. That is a service we already run — we get on a call, install it on your machine start to finish, and show you what we are doing while we do it, so the next change is one you can make yourself.
Tiers, timing and what each one includes live on the consulting page.
The tier that covers a full Claude Code install is The Full Build — $500: two sittings, your machine, start to finish — migration, memory, autonomy, and the walkthrough while we do it.
One of these comes home with you — no add-on, no upsell. Your companion gets a body. It stands in its own room, and the room's palette colours the whole app — so switching familiars changes the light you sit in, not just the picture.
A creature nobody else has — your own body, your own room, your own palette running through the whole app. Tell us what it is and we will tell you what that takes.
Ask us →Want one that’s yours alone? Custom familiars are drawn to order and quoted per creature, from $350 — on top of the six that already come with the app. Drawn, animated and given its own room palette, so the whole app changes colour around it.
No list, no signup form, no third party holding your address. Email us the word companion and we will write to you once, when it goes out.
hello@sinandsarah.com →Already own the source code? This is a different thing — the app is an installer you run, not a build-it-yourself kit. The code catalog is here.