Making plans with a friend.
Doing something healthy with another person (a walk, a stretch, a swim, a call while you both wander your own neighborhoods) is one of the oldest medicines there is, and it works better when someone's waiting for you. This is the tool for making that plan, near or on the other side of the world, without either of you opening up your calendar to the other. There's a technical page for people who build and break software.
Together is the reusable protocol
It supplies common rules for proposing, answering, agreeing, changing, and recording something people decide to do together. The same rules can support several applications:
- Together + time → making plans
- Together + purchase terms → buying together
- Together + several households → buying circles
- Together + a confirmed plan → local reminders
- Together + an offer and agreement → service exchange
Message Delivery carries the signed, sealed messages. It is infrastructure used by Together, not a separate application.
The idea, in one picture
Two homes, two calendars, and one envelope between them. Neither calendar ever opens to the other. Each of you keeps your own record of what was agreed, the way people always have.
Your archive already keeps track of your own life, including your calendar. Now, with your say-so, it can propose a time to a friend's archive, hear back a plain answer, and put the plan on your calendar. Neither of you ever opens your calendar for the other to look through.
Two houses
You have an archive. Your friend has her own, somewhere else: maybe across town, maybe across an ocean. Neither archive moves in with the other, and neither gets a copy of the other's. The two of you exchange invitations, the way you'd exchange a phone call, and each of you keeps your own record of what was said.
The story, with made-up people
Carmen, in Palo Alto, wants a walk-and-talk with her friend Marta, in Madrid. They've known each other for years, and they swapped keys long ago (more on that below). Carmen's archive proposes two possible times for Saturday. Marta's archive checks her own calendar (quietly, at home) and finds that one of them collides with lunch at her mother's. So Marta answers with a different time. Carmen agrees. Done.
The six steps
You think of something healthy to do together. A walk, a stretch, a swim, a call while you both walk your own neighborhoods. Pick a couple of times that could work for you.
Your archive sends the ask, and only the ask. Just the activity and a couple of times. Nothing about your calendar travels with it.
Your friend's phone checks HER calendar, privately, at home. Nobody outside her house sees it happen. You do not see it, and neither do we.
She answers in a sentence. "Yes." Or "how about 10 instead of 9?" That's the whole reply.
You confirm, and it lands on both calendars. Each of you sees it in your own time, in your own zone. Neither of you does any math.
Plans change, or you want to do it again. Cancel it with one tap, or duplicate it for next Saturday — also one tap.
Your calendar never leaves your house
What your friend's phone checks. When you propose a walk, her phone looks at HER calendar (privately, at home, the way you'd flip open your own planner). Nothing about that check is visible to you, or to anyone else.
What comes back to you. One sentence. "Yes." Or "how about 10 instead of 9?" That's the whole message. Her free afternoons, her busy ones, and why Tuesday doesn't work for her all stay with her.
The difference that matters. Some calendar tools show your whole week to anyone who asks: every free hour and every busy one, laid out like a grid. Your friend never sees a grid of your week. She sees one question, and she answers it on her own terms. This only ever sends sentences.
Known people only, on purpose
How the "key" works
You and a friend swap a key once — the same way you'd trade phone numbers. In person, over a call, however you already talk. Once you have swapped a key, your archives can send each other invitations. Until then they cannot find each other at all.
Why that's the whole point
There is no directory here, no search, and no "people you may know." A message from someone you haven't swapped a key with never reaches you. Your archive turns it away quietly, before you ever see it. That's what makes this spam-proof, and (for something built around health, memory, and the people we've lost) grief-proof too.
Across the world, without the math
Palo Alto and Madrid are nine hours apart. 9 in the morning here is 6 in the evening there. Normally that means somebody squints at a clock and does arithmetic, and somebody still gets it wrong.
9:00 AM — Palo Alto (you)
6:00 PM — Madrid (Marta)
Every invitation carries both clocks. You see your time; your friend sees hers. Nobody converts anything by hand. When the clocks change in spring, both of you still see the right hour.
Delete and do-again
Plans change. Rain, a cold, a week that falls apart: cancel the walk with one tap. Everyone who was invited sees that it's cancelled. Your history stays put. You can look back and see the walk was planned and then called off, the same as any plan you'd have mentioned out loud to a friend.
Liked it? Doing it again is even easier. Duplicate makes a new invitation for "same walk, next Saturday": one tap, same friend, a new time to agree on.
The walk happened. Now what?
You mark it done. That's between you and your own archive: a private note that you moved, with whom, for how long. The note stays home. Your friend's archive never gets it, and neither do we.
The celebrating is still yours to do out loud, the way it always was. The system's only job was getting you both to the same street corner at the same time.
Where this stands
Built and tested July 9, 2026, as a working prototype, on invented data. Two made-up archives, paired the way this page describes, ran the whole exchange (propose, counter, confirm, add a third friend, cancel, duplicate, mark done), watched by 126 automated checks, including an independent attempt to break it that found real problems and got them fixed before this page was written.
There is no app to download yet. The pieces ship in the open, in order, the same as everything else here, and this page will say so, dated, when that changes.
Your archive stays yours. Together exchanges invitations and replies without opening either archive to the other.
One piece is still being decided: message delivery (the part that physically carries an envelope from your house to your friend's) today uses a private, trusted folder. A live connection between two strangers' devices out in the world does not exist yet. That's a decision waiting on infrastructure.
How to help, and how to tell us something's wrong
See a problem, or something that worries you? On the main site: Write to us → "feedback," or Write to us → "security" for good-faith lock-testing: welcomed, credited, and protected by a safe harbor written into our Terms, §15.
Want to build it with us? Apply → "build," and read the technical page — it shows exactly what the tests enforce today, and what has yet to be built.
Just following along? The "New in this place" board on the home page announces every change, dated.