> ## Documentation Index
> Fetch the complete documentation index at: https://docs.atrum.fun/llms.txt
> Use this file to discover all available pages before exploring further.

# Introduction

> A prediction market where nobody can see how much you bet.

On every prediction market today your position is public — size, timing, entry, and profit
or loss. Anyone consistently good gets copied, and their edge is gone before they have
realised it.

Atrum hides the amount. Bets are encrypted on-chain and summed without ever being decrypted,
so the market shows live odds while individual stakes stay private. Winnings are claimed
through a zero-knowledge proof, so a payout cannot be traced back to the bet that earned it.

<Note>
  **Everyone still sees that a bet was placed and which side it backed. Nobody sees how much,
  or whose.** That line is exact, and [Privacy model](/concepts/privacy-model) draws it
  precisely. If you are about to describe Atrum to someone, read that page first.
</Note>

## Why this cannot be retrofitted

Homomorphic encryption lets a contract **add** ciphertexts. It does not let it **compare**
them — and order matching *is* comparison. So an encrypted order book is not a hard
engineering problem, it is a mathematical impossibility with today's cryptography.

Atrum is parimutuel because that is the only mechanism that works when the contract can add
but cannot see. See [Why parimutuel](/concepts/why-parimutuel).

## What you can do

<CardGroup cols={2}>
  <Card title="Place a private bet" icon="lock" href="/guides/place-a-bet">
    Deposit, bet, and have the amount stay hidden the whole way through.
  </Card>

  <Card title="Understand the privacy" icon="eye-slash" href="/concepts/privacy-model">
    Exactly what is hidden, what is not, and what the limits are today.
  </Card>

  <Card title="Read the architecture" icon="sitemap" href="/concepts/architecture">
    Encrypted accumulator, commitment tree, sequencer, publisher.
  </Card>

  <Card title="Market lifecycle" icon="timeline" href="/guides/lifecycle">
    A market from creation through resolution to payout.
  </Card>
</CardGroup>

## Status

Live on **Monad testnet**. The full private path works end to end: deposit → encrypted bet →
settlement → private redemption → withdrawal.

<Note>
  Currently running on testnet while the mainnet launch is prepared.
</Note>