---
title: "Overview"
description: "BTR is a decentralised exchange running an oracle-priced, multi-asset AMM: single-sided liquidity, depth and spread that follow the pool's own inventory."
audience: both
type: explanation
status: live
lang: en
updated: "2026-08-30"
publish: true
---
# Overview

BTR is a decentralised exchange. You swap on it, or you provide liquidity to it,
and both run on chain against pools whose state and pricing you can read and
check yourself. See [deployed instances](/docs/2-1-contract-addresses) for where
it runs and at which addresses.

The exchange runs on an automated market maker of its own design, the Adaptive
Inventory Market Maker (AIMM), a synthesis of asset-liability accounting, inventory-aware
mid-pricing and singleton multi-asset pooling whose prior art is catalogued in
[Foundations](/docs/foundations). The difference from a conventional AMM is where
the price comes from. A constant-function pool has to be taught its price by
arbitrageurs walking a curve, and pays them for the lesson on every move. A BTR
pool is told the price by a signed oracle mark, so it spends its machinery on
inventory instead: how deep to quote, which side to favour, and what to charge
for the risk it is carrying.

So a BTR pool holds several assets and quotes them from that live mark rather
than from its own reserves. Depth concentrates where an asset actually trades,
and every quote leans on the pool's inventory: the side that restores balance is
priced better than the side that pushes it further out.

Assets are not arranged around a single hub. Each one anchors to a correlated
parent, and a swap prices along the path between its two endpoints, so two assets
sharing a parent trade through that parent and never touch the base. The base is
the pool's unit of account and the root the tree ultimately resolves to, not a
leg every trade is routed through.

What that means depends on which side of the pool you are on:

- **Liquidity providers**: one token in, one fungible position, no range to
  choose and nothing to rebalance.
- **Traders**: quotes are always competitive on the side that rebalances the
  pool's inventory, and competitive both ways at equilibrium; the spread is
  symmetric, and it tracks volatility rather than sitting at a fixed tier.

Anyone can deploy a pool, though administering one is a separate, gated matter.

## Core features

| Feature | What it does |
|---------|--------------|
| [Inventory-aware pricing](/docs/1-1-1-inventory-management) | Coverage ratios move the mid against flow that drains a leg and toward flow that refills it; the spread itself carries no coverage term |
| [Shared liquidity](/docs/1-1-2-liquidity-shaping) | One reserve serves every asset in the pool, shaped by quartic I-spline presets; legs are grouped by correlated asset class so that flow draining one tends to arrive against another ([Pool Composition](/docs/2-3-pool-composition#why-several-cores-rather-than-one)) |
| [Anchor path](/docs/1-1-3-anchor-path-pricing) | Assets price through a tree rooted at the base token (`MAX_DEPTH = 4`), along the unique path via the lowest common ancestor |
| [Coverage IL protection](/docs/1-1-1-inventory-management#5-withdrawal-haircut) | Reserves and liabilities are tracked per leg, so an exit from an under-covered leg is haircut rather than paid at face |
| [Price sources](/docs/3-4-oracles) | Marks come from any contract implementing `IOracle`; cash-collateral units use the internal par helper instead |

## Read next

| Page | Content |
|------|---------|
| [Manifesto](/docs/manifesto) | Problems, solutions, posture |
| [Foundations](/docs/foundations) | Prior art (Avellaneda-Stoikov, Platypus/Wombat, Curve v2) |
| [1. AIMM](/docs/1-overview) | Modules, pricing, routing |
| [2. Deployments](/docs/2-overview) | Deployments per chain (Arc Testnet today), registry, pools |
| [3. Security](/docs/3-overview) | Roles, pause, oracles, flow guards |
| [4. User Guides](/docs/4-overview) | Swapping, providing liquidity, assets and the hub |
| [5. Developer Guides](/docs/5-overview) | On-chain integration, API & SDK, operations |
| [6. Roadmap](/docs/6-overview) | Specified but unbuilt designs; nothing in this section is deployed |
| [Glossary](/docs/glossary) | Terms |
| [Risk Disclaimer](/docs/risk-disclaimer) | Legal risk surface |