Kairo
One account, every game.
Eight characters or more. You will need to confirm your address before you can play with anybody.
The Kairo account service stores your sign-in and nothing else. Last updated 1 September 2026.
What this service holds
- Your email address. Used to sign you in, to confirm the address once, and to reset a forgotten password. That is all. There are no newsletters and nothing to unsubscribe from.
- The name you chose to be called in games.
- Your password, only as an argon2id hash. The password itself is never stored and the hash cannot be turned back into it.
- Your sessions — one row for each browser you are signed in on: when it started, when it was last used, and whether it has been signed out. Only a hash of the cookie is kept, so a copy of this database does not hand anybody a way in.
- Verification and reset links, again only as hashes, with what each is for, when it expires, and whether it has been used. Each works once.
- Short-lived counters keyed by IP address and by account, which is how repeated password guesses are slowed down.
What it does not hold
No games, no moves, no seats, no problem reports — those belong to the game you were playing and never reach this service. Monument keeps those, and says so in its own privacy notice.
No analytics, no advertising, no tracking, and no third-party cookies. The only cookie is the one that keeps you signed in.
Who else sees it
Three companies, each doing one job:
- Postmark (Massachusetts, USA) sends the verification and password-reset emails. They see your address and those messages.
- Fly.io (USA) runs this service.
- Neon (USA) hosts the database it stores.
Nobody else. It is not sold, rented, or shared for advertising, and there is no arrangement under which it could be. If that ever changes, this page changes first.
How long it is kept
Your account until you delete it. A session until you sign out or it is revoked. Reset links expire within the hour, verification links after a week, and both work once. The rate-limit counters are discarded as their window passes.
Getting your data, and getting rid of it
Sign in to the game and use your account page to export what is held about you.
To delete the account, email the address below and we will erase it: your address, the name you chose, and your password hash go, every session is signed out, and any outstanding links stop working. Some of what a game keeps survives for the sake of the people you played with — Monument's notice explains exactly what, and why.
Children
Kairo is not aimed at children and we do not knowingly hold data about anyone under 13.
Asking us something
Email hello@play-kairo.com. We are one or two people, not a department, and you will get a real answer.