Privacy
Privacy, in plain words.
Your novel is yours, and so is what you tell Quilt about it. Here is everything Quilt keeps, where, and who else touches it.
Last changed 5 November 2026
The short version
- Your books are saved on your device. They go to Quilt's server only if you sign in, so your other devices can have them.
- When Thimble writes, the parts of your book it needs are sent to Anthropic, which runs the AI. Anthropic doesn't train on them.
- Quilt doesn't sell anything about you, show ads, or use trackers. This website sets no cookies.
- Ask and we delete your account and everything in it.
On your device
Everything you write in Quilt (your books, comments, notes, versions, pictures, and your settings) is saved in the browser or the Mac app on your device as you go. If you add your own Anthropic API key, it stays on your device too, and is sent only to Anthropic.
If you sign in
Signing in is optional. If you do, Quilt's server keeps:
- Your email address, to send your sign-in code. Codes and sign-in sessions are stored only in scrambled (hashed) form.
- Your books and their pictures, so they sync between your devices. Each book is kept as a single document with its version number.
- How much Thimble you used each day: a count of requests and words (tokens), so everyone stays inside a fair allowance. Not what was asked or written.
The server runs on Railway, in the United States. Quilt doesn't look through your books. The only reasons anyone would open one are if you ask us to help with it, or if the law requires it.
When Thimble writes
Thimble is built on Claude, by Anthropic. When it writes a step, answers a question or reads a draft, Quilt sends Anthropic what that job needs: your answer, the steps it builds on, and sometimes pictures you've added. If you're signed in and using Quilt's allowance, this passes through Quilt's server on its way, and isn't stored there. With your own key, it goes straight from your device to Anthropic.
Under its commercial terms, Anthropic doesn't train its models on what's sent through its API, and it keeps it only briefly. Anthropic's own privacy policy has the details.
Who else
Only the services that make Quilt work, each for that one job:
- Anthropic
- runs Thimble.
- Railway
- hosts Quilt's server and its database.
- Resend
- sends the email with your sign-in code.
- Cloudflare
- looks after Quilt's domain names.
Nothing about you is sold, rented or shared for advertising.
This website
writewithquilt.com has no analytics, no cookies and no third-party scripts. If you pick a look for the page, your browser remembers it on your own device. Like any web server, ours sees your IP address when the page loads, and short-lived server logs may record it.
Deleting
To delete a synced book from the server, or your whole account and everything in it, write to hello@writewithquilt.com from the email you sign in with, and it's done within a few days. Buttons for both are on their way. Books you've never synced live only on your device, and deleting them in Quilt deletes them.
Questions about any of this go to the same address.