Kolaboro / Deal room
A private room for your purchase
Notes, a checklist and small documents you share with your lawyer or family, encrypted in your browser before anything leaves it. We store only ciphertext and cannot read it. Every entry is signed by its author and chained to the one before, so nobody, us included, can quietly change the history.
Open a new room
A room is just a link. Creating one makes a random 256-bit secret in your browser and puts it after the # of the link, the part browsers never send to any server. When you open a link, this page moves the key out of the address bar into this tab's memory before anything else runs. Keep the link from the Share box: it is the only key.
No account, no email. Opening a room on this device also creates a signing key for you here, stored in this browser and never exported.
Share
Save your link now. The address bar does not show the key, on purpose. Copy the full-access link below into a password manager or a note only you can read.
Full access (can read and add): give it to your lawyer.
Read-only: for family who should see but not change anything.
Send links through a channel you trust (in person, Signal). Anyone holding a link has its access, and links cannot be revoked one by one: to cut someone off, export, open a new room and share the new link.
Checklist
Files
Notes and timeline
Who has written
Each author is a signing key. Compare these codes with the people you invited (read them out on a call) to be sure an entry came from them.
You on this device
Your key code:
The security model, plainly
What we can see
- A room id (a one-way hash of the key) and how many entries it has, their sizes and times.
- Your IP address when you connect, like any website.
- Nothing else: no text, no file names, no names of people. Those are inside the encryption.
What we cannot do
- Recover a lost link. We never have the key. Lose every copy of the link and the room is unreadable forever, for you and for us.
- Read your room, even if asked by anyone: we do not hold anything that decrypts it.
- Change an entry or insert a fake one without the timeline showing "tampering detected".
How it works
- AES-256-GCM, key derived with HKDF from a 256-bit secret in the URL fragment. Each entry is bound to this room and its position.
- Each entry is signed with its author's ECDSA P-256 key, made in the browser and not exportable.
- Each entry includes the SHA-256 of the previous one: a hash chain. Your browser checks all of it every time.
- Your device remembers the last entry it saw, so a server that deletes recent entries is caught.
Limits you should know
- Anyone with the full link can read and write. Treat it like a house key.
- The key is in the link. This page removes it from the address bar on arrival, so it does not stay in browser history, but wherever you paste the link keeps a copy. Use a private window on shared computers. This page loads no analytics scripts of its own; anything our hosting network adds sees only the address without the key, and the room is marked so session-recording tools mask it.
- Small files only (200 KB). Larger documents: share them another way and add their fingerprint here.
- A malicious version of this page could steal keys. The code is readable: room.js.