Built so we can't read your brain.
Hippo handles your most intimate work data — your projects, your clients, your voice, your decisions. So we designed it so the secrets never reach us in the first place. Your keys and plaintext stay on your Mac — there's no readable copy of your brain anywhere else.
Your brain never touches a server.
No copy of your memories, keys, or index ever leaves your Mac. The only thing our backend ever knows is who’s paying — never what you know. There’s nothing of your brain to breach, leak, or subpoena, because it was never on our side.
Keys & plaintext stay on your Mac
Encryption keys live in the Secure Enclave. Your vault and the searchable index that powers it stay on your Mac and never leave the device — there's no cloud copy of your brain to read.
Every fact has a receipt
Every memory is inspectable, editable, and deletable in each project's Brain view. Every line in a packet drills back to its source. Nothing is hidden from you — and nothing is shown to us.
Honest revocation
Revoke any agent's future access in one click. We cut it off and log it. We never pretend a model “forgets” what it already saw — revocation is a future-access cutoff, and it's recorded.
Fiduciary by design
No ads. No data resale. No selling your brain to anyone, ever. Hippo's only business is the subscription — your incentives and ours point the same way.
The secrets never reach us.
Most apps promise to protect your data. Hippo's promise is stronger and simpler: we never get readable access to it at all. The compute that builds your brain runs where the data already is.
Reasoning — the actual writing — runs on the AI you already pay for. Retrieval — assembling a Context Packet — runs locally. Learning — organizing memory — runs on a small model right on your Mac. Nothing about your projects leaves the device for us to read.
That's not only a privacy stance — it's the architecture. Because we can't see your data, there's nothing on our side to breach, leak, or subpoena. You can't leak what you never had.
The short version: Hippo is a safe in your house — not a vault in our bank.
One project's AI never sees another's data.
A project is an isolated, sealed brain — a company, a client, a personal project, or your own work brain. Projects never share data with each other. When you brief an AI for one project, the packet is scoped to that project alone; every other project is walled off. For consultants and fractional execs juggling several clients at once, that per-project confidentiality wall is the whole point: one client's AI can't touch another client's data, and the ledger proves it.
Proof of what each agent saw.
Every read, every approved write, every revocation — logged like a bank statement. Aligned, timestamped, scoped to a project. You can always answer the question: who saw what, when, and with whose permission?
- ✓Every read, logged. When an agent pulls a packet, the entry records the agent, the scope, and the project. Cross-project reads simply can't happen.
- ✓Guarded writes. An agent that wants to write a new fact back into your brain has to be approved by you — and the approval is on the record.
- ✓Revocation is honest. The ledger shows the cutoff, not a fantasy. Future access ends; we don't claim the model unlearns the past.
- ✓Audit-ready. The ledger is built to be shared and audited — the answer to “prove the wall held” is one export away.
Precise about privacy.
Trust is built on honest claims. Here's exactly where the lines are.
What we promise
- ✓Your keys and plaintext never leave your Mac in readable form.
- ✓You can inspect, edit, pin, or delete any memory at any time.
- ✓Revoking an agent ends its future access and logs the cutoff.
- ✓Projects stay walled off from each other — provably.
What we won't pretend
- ›We won't claim a model “forgets” something it already saw. Revocation is forward-looking.
- ›We won't claim to control what a third-party AI does with text once you've sent it.
- ›We won't over-capture to look smart — Hippo is conservative on purpose.
Calm, fast, and a little stubborn about your privacy.
Start free on one Mac. Zero-knowledge on every plan, including Free.
60 seconds · no account · no API keys