What we keep, and why.

Substance is a place for writing. We keep what the writing needs and little else, we show nothing of yours to anyone you did not choose, and we sell nothing about you to anyone. There is no advertising here.

What you give us

Your email address, a handle, the name you write under, and a password. What you add to your profile. Your words: posts, responses, seeds and drafts. And what you do with other people's words: what you read, like and keep, whom you follow, and whom you have muted, blocked or reported.

What we notice

The network address and device you sign in from, kept with that sign-in. If you allow pushes, the token your phone gives us for them. And a plain record of what happens on Substance - a post was written, a page was opened, someone came back - so we can see whether Substance is working. It is never shown to another member, never sold, and never handed to anyone. The only cookies are the ones that keep you signed in, remember your clock, and tell us whether the front door led anyone in. A letter we send you carries a one-pixel picture; when your mail client loads it we learn that the letter was opened, and nothing more. That mark is kept ninety days and then let go.

When the house looks

A steward may open your page as you see it - your circle, your profile, what greets you when you arrive - to see whether Substance is worth arriving for. That look only reads: nothing can be written, published, liked or followed in your name, and it leaves no mark on anything, so no writer is ever told the house read them. What is yours alone is sealed to it: your seeds, your drafts, what you write with Cleo, your letters, what you keep, your settings, and anything you kept to yourself. Every such look is recorded, with who looked and at whom.

Cleo

Cleo reads what you are writing so she can ask you a question about it. Nothing you write with her is stored, used to train anything, or shown to anyone but you. Before a post is published it is checked to be written by a person; if the check is wrong and you say so, a person reads it.

Who else touches it

The services that host Substance, carry its email, read posts aloud, transcribe dictation, and deliver pushes to your phone each see only what their work needs, and keep nothing. None of them is an advertiser.

Who reads you

You decide. A post goes to your circle, to a named circle, or to everyone; a profile can be open to guests or kept to members. Nobody is shown a count of who follows you, who read you or who liked what you wrote; the writer alone is told, in words. A member who blocks you is gone from your pages, and you from theirs.

What you may do

Take your words with you at any time, as one plain file, from your settings. Change anything about your account there too. Delete your account, and everything you gave us goes with it.

If you are in the European Union or the United Kingdom, these are your rights of access, portability, rectification and erasure; you may also object to or limit what we do with your data, or complain to your supervisory authority. Our lawful bases are our agreement with you as a member and our legitimate interest in keeping Substance working. No automated decision with legal effect is made about you.

Children

Substance is for people of sixteen and over. If you know of an account held by anyone younger, write to us and it will be closed.

Keeping it safe

Everything travels encrypted, passwords are never kept in the clear, and everything is backed up. If we ever learn that your data was exposed, we will tell you.

Changes, and how to reach us

If these words change in a way that matters to you, we will say so on Substance before the change takes effect. For anything about your data, write to contact@substance.app. A person answers.