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

# Introduction

> Perpetra is a perpetuals DEX built on Hedera

Perpetra is a decentralized perpetuals exchange deployed on Hedera. It lets traders open leveraged long or short positions on an asset without an expiry date, while the protocol keeps the trade price anchored to the real market through a funding mechanism.

## What makes Perpetra different

Most on-chain perpetuals protocols use a pooled-liquidity model, where traders take the opposite side of a shared vault (GMX-style). Perpetra instead uses a **hybrid orderbook model**:

<CardGroup cols={2}>
  <Card title="Off-chain matching" icon="bolt">
    Orders are signed by traders and matched off-chain by Perpetra's matching
    engine, so price discovery happens the way it does on a traditional
    orderbook exchange: bids and asks, not a pooled price curve.
  </Card>

  <Card title="On-chain settlement" icon="link">
    Once two orders match, settlement (position updates, collateral movement,
    PnL) happens on-chain through Perpetra's smart contracts, so custody and
    final state always live on Hedera.
  </Card>
</CardGroup>

This gives traders orderbook-style execution (tighter spreads when there's depth, real limit orders) while keeping funds and final settlement fully on-chain and non-custodial.

## Who these docs are for

<CardGroup cols={2}>
  <Card title="Traders" icon="chart-line" href="/trading/placing-orders">
    Learn how to place orders, manage margin, read your liquidation price, and
    understand funding. Start with the Trading Guide.
  </Card>

  <Card title="Developers" icon="code" href="/architecture/overview">
    Learn how Perpetra's contracts, matching engine, and keepers fit together.
    Start with Protocol Architecture.
  </Card>
</CardGroup>

## How Perpetra is built, at a glance

* **Smart contracts (Solidity):** handle custody, position state, risk checks, and settlement on Hedera's EVM.
* **Matching engine (off-chain):** matches signed orders and submits settlement transactions.
* **Keepers:** independent bots that trigger on-chain actions the contracts can't trigger themselves: matching, liquidations, funding updates, and oracle price pushes.

The rest of these docs walk through each layer in more depth, starting with how a trade actually gets placed.