The running memory
of your household.
Scan the letters, save the pages, ask a question later. A shared brain that remembers what the GP said, when school starts, and where the recipe went.
Open source and self-hostable.Read the code
- She moved to AntwerpLast monthSaved from her text
- She’s been plant-basedSince JanFrom a chat
- She introduced you to MarcLast yearNote · ‘intros’ brain
Outcomes over organization.
Built for those who do not care where things are stored, as long as they are found, at the right time and in the right place.
How it works.
Scan it or save it. The rest sorts itself out.
- Phone
Scan the letters that matter.
School letters, medical notes, the appointment card. Point your phone and BrainExtension keeps the dates.
- Browser
Save the page, not the link.
A recipe, a how-to, the thread with the answer. One click, and your extended brain keeps the method, not a bookmark that rots.
- Connections
Connect what you already use.
School email, the family calendar, your photos. Whatever comes in links itself to the people and dates you already have.
- Voice
Or just talk.
Say what the GP said, or what you decided about the holiday. If a detail's missing, your second brain asks a few short questions until it has the story.
Everything you save connects.
Save anything. Your extended brain draws the links itself, so you never file anything.
Your follow-ups stop slipping.
Say you’ll RSVP to Lily’s party. BrainExtension catches it, ties it to the date, and pings you the day before.
Six months apart, still linked.
The plumber’s quote from March sits beside August’s invoice and the photo of the leak. Your second brain keeps them in one thread.
- MCP · REST API
Integrates with your tools.
Ask in Claude or ChatGPT. The answer still comes from your material, plugged in over MCP and REST.
Answers come from what you’ve actually saved.
Every answer names its source.
5mg lisinopril, mornings, review in six weeks. GP note, 18 June
28 October, back 5 November. School letter, 3 Sep
Pasta con la mollica — in your Sicilian dinners brain. Want it for four?
V60 02. Manual you scanned, March
12 June, €18 in cash. School letter, 20 May
Open Source on GitHub,
Yours to Self-Host.
BrainExtension will be free and open source under Apache 2.0 license, after completing the private beta & audit.
Open source
On GitHub under Apache 2.0. Read it, fork it, audit it.
Self-hostable
Run it on your own machine. Same code, no account with us.
No lock-in
Swap the model, bring your own key, export every memory.
Private by default
Personal brains stay private. We never train on your content.
One price for the whole house.
Charged to the household, not the head. One bill, one renewal, and each person’s own brain stays their own.
Free
One person, forever, not a trial
- One brain, one person
- Notes, people and follow-ups in one place
- Automatic links between memories
- Browser extension
- A daily allowance of AI recall
Family
€290 a year, two months off. Up to 5 people.
- Up to 5 people, each with their own brain
- A shared household brain: letters, dates, the paperwork
- Scan a letter, save a page, or just talk to it
- Follow-ups and dates caught as they come in
- Voice capture and Telegram
Family Max
€590 a year, two months off. Up to 8 people.
- Everything in Family, for up to 8 people
- Voice interviews that write themselves down
- Facts rechecked on a schedule
- Bulk import: old photos, old mail, the box of paper
- The strongest models
More than eight under one roof
Grandparents, a carer, a house-share that grew. Add people past the eight in Family Max and each one keeps a brain of their own.
added to Family Max
Prices include VAT. Cancel any month. Self-hosting is free at every tier.
Start a family brain.
Free forever for personal brains. Leave your email and we’ll send your invite.
One email when your invite is ready. Nothing else.