> For the complete documentation index, see [llms.txt](https://docs.brotocol.xyz/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.brotocol.xyz/developers/brotocol-contracts/contracts.md).

# Overview

Brotocol's core on-chain functionalities are implemented through a set of smart contracts deployed on Stacks and EVM-compatible networks (see complete list of EVM chains [here](/developers/deployments/chains/evm/ethereum-contract-addresses.md)).

Their primary function is to provide a bridging mechanism, allowing the movement of assets between Bitcoin and other DeFi blockchain ecosystems. Additional features include Bitcoin swaps, cross-chain liquidity aggregation, integration of staking protocols and the Brotocol Governance System.

The subsections below describe the purpose, scope and interactions of the Brotocol contracts. Each subsection provides a detailed overview of each smart contract and its main variables, features, error codes and events.

## Chains

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[Stacks](/developers/brotocol-contracts/chains/stacks.md)
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[EVM](/developers/brotocol-contracts/chains/evm.md)
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