Privacy middleware for AI

Use the best AI
without handing over
your data.

Decoy sits between you and frontier models. Sensitive details are swapped for opaque tokens before they leave your device, so the model can do its work without ever seeing what's underneath.

The Problem

The smartest AI ever built. And the data can't touch it.

The customer list. The salary review. The patient cohort. The deal pipeline. The board pack. The contracts. The data worth analysing is exactly the data you can't send.

So you work around it. Strip columns. Rename clients. Paste a sanitised version and hope the rest is enough. The reasoning is right there. Your data can't get to it.

The Idea

Frontier models don't need your data. They need its shape.

Decoy dehydrates your data before it leaves the device. The cloud reasons over the dry version. Your machine rehydrates the answer locally, with the real values restored. The model gets the problem. Your data stays where it belongs.

How It Works

This is what the cloud actually sees.

The left is yours. The right is what crosses the network. The mapping below is the difference, and it never leaves your browser.

Your input Local

Acme Corp bought 4,200 units in Q3 at $89 per unit. Their account manager Sarah Chen reports they're considering doubling their order in Q4. Forecast revenue and flag risk.

Sent to AI Decoy active

[C_8847] bought [N_2201] units in [P_03] at [N_2202] per unit. Their account manager [P_4419] reports they're considering doubling their order in [P_04]. Forecast revenue and flag risk.

Local Mapping
held in browser memory · cleared on session end
Acme Corp [C_8847]
Sarah Chen [P_4419]
4,200 units [N_2201]
$89 [N_2202]
Q3 [P_03]
Q4 [P_04]

What This Does

Three things change about how you work.

01

The data stays.

The cloud model never sees a name, a number, a customer, or a salary. The mapping is held in your browser memory and destroyed when you end the session. It's not "we promise we won't look." It's "there is nothing for anyone to look at."

02

The maths is right.

LLMs are unreliable at arithmetic. Decoy doesn't ask them to do it. The cloud plans the analysis. Your machine computes it. Every formula is visible, every input is auditable. You can show your CFO the working.

03

The compromise goes.

You stop stripping the columns. You stop renaming the clients. You stop pasting the sanitised version. The architecture handles what the workaround was for.

What It's For

For anyone who'd rather not hand over what they're working on.

Decoy is for people who treat their data as theirs. Whether that's a patient cohort, a customer book, a salary review, or a deal pipeline, if it would be inappropriate to paste into a cloud chat, it's the data Decoy is built for.

What it does today: analytical work on structured data. Forecasting, comparison, ranking, aggregation, variance, cohort summary. The kind of question you'd otherwise put in front of Excel, but you'd rather ask the way you'd ask a smart colleague over Slack.

What it doesn't do yet: free-text generation, document summarisation, conversational AI. The architecture splits planning from execution, which fits analytical tasks cleanly. Other shapes of work are on the roadmap. Different problem, different design.

Where It Fits Today

  1. 01 A finance lead modelling Q4 forecasts across a real customer book.
  2. 02 A sales operator scoring a deal pipeline by margin and risk.
  3. 03 An HR analyst comparing salary bands across departments.
  4. 04 A consultant pulling apart a client's actuals before a strategy session.
  5. 05 A founder breaking down their MRR by cohort the night before a board meeting.
  6. 06 A government analyst working on a cohort that can't leave the agency.
  7. 07 A clinician summarising patient cohort data without sending it.
  8. 08 A lawyer comparing settlement terms across past matters.

Why Trust Decoy

Privacy by architecture, not by promise.

"Trust us" is the weakest possible promise. Decoy doesn't make it.

Sensitive values are dehydrated locally before the prompt leaves your device. The mapping between tokens and real values is held in your browser and destroyed when the session ends. The cloud sees structure. Your machine rehydrates the answer using the real numbers. Network logs show exactly what was sent and what wasn't. You bring your own API key. Your chosen provider's terms apply. Decoy doesn't intermediate.

The architecture is the trust signal. The product would not work if the architecture broke.

Read the whole thing ›

Early Access

We're picking our first customers carefully.

Decoy is in private alpha. We're letting people in slowly because each early customer shapes what gets built next. We're looking for finance leads, operators, analysts, and teams working with sensitive data on a regular basis. People who'd actually use this and tell us where it's wrong.

If that's you, send a note. Tell us what you do, what you'd reach for it on, and what you'd want it to do that it probably doesn't yet. We read everything. We reply fast.

Get in touch ›

Built in Sydney. Working in public.