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

# Introduction

**AstralBeam** is a secure, bidirectional bridge between **Casper Network** and **EVM-compatible chains** such as Ethereum, Base, and Polygon.

## What is AstralBeam?

AstralBeam lets you move tokens between Casper and EVM chains in a few clicks. Lock a token on one side, receive its equivalent on the other - and bridge it back whenever you want.

Security is the core design goal. Every transfer must be independently verified and approved by multiple independent relayers, and the cryptographic proof of your deposit is checked on-chain before any tokens are released. No single party - not even the bridge operators - can move funds alone.

### Key Features

* **Multi-Chain** - Bridge tokens between Casper and multiple EVM chains
* **Independently Verified** - Every transfer is cryptographically proven, not just trusted
* **Multi-Signature Security** - A majority of independent relayers must approve every transfer
* **Non-Custodial** - Your tokens stay under your control until you initiate a transfer
* **Finality Protection** - Transfers only proceed once the source chain has finalized them

## How It Works

```mermaid
flowchart LR
    subgraph Source[Source Chain]
        Deposit[You lock or burn tokens]
    end

    subgraph Relayers[Independent Relayer Network]
        Verify[Each relayer verifies the transfer cryptographically]
        Approve[Majority approval required]
    end

    subgraph Destination[Destination Chain]
        Receive[You receive tokens]
    end

    Deposit --> Verify --> Approve --> Receive
```

1. **You start a transfer** - Lock (or burn) tokens on the source chain
2. **The network waits for finality** - The transfer must be irreversible on the source chain
3. **Relayers verify independently** - Each relayer cryptographically confirms your transfer really happened
4. **Majority approval** - Only with enough independent approvals are tokens released
5. **You receive tokens** - The equivalent token arrives in your destination wallet

Read more in the [Security Model](/security/security.md).

## Supported Transfers

| Direction    | You send                        | You receive                       |
| ------------ | ------------------------------- | --------------------------------- |
| EVM → Casper | ERC-20 token                    | Equivalent CEP-18 token on Casper |
| Casper → EVM | Bridged CEP-18 token            | Original ERC-20 token back        |
| Casper → EVM | Casper-native token (e.g. CSPR) | Wrapped ERC-20 version            |
| EVM → Casper | Wrapped ERC-20                  | Original Casper-native token back |

## Supported Networks

### Testnet (Live Now)

| Network                 | Status      |
| ----------------------- | ----------- |
| Casper Testnet          | **Active**  |
| Ethereum Sepolia        | **Active**  |
| Base Sepolia            | **Active**  |
| Polygon Amoy            | **Active**  |
| Robinhood Chain Testnet | **Active**  |
| Arbitrum Sepolia        | Coming soon |
| BNB Smart Chain Testnet | Coming soon |

### Mainnet

Mainnet launch is planned following thorough testnet validation and security audits.

## Quick Links

### For Users

* [Getting Started](/getting-started/user-guide.md) - Connect your wallets and bridge tokens
* [Supported Tokens](/using-astralbeam/supported-tokens.md) - List of bridgeable tokens
* [Troubleshooting](/using-astralbeam/troubleshooting.md) - Common issues and solutions

### For Developers

* [API Reference](/api-reference/api-reference.md) - REST API documentation
* [Smart Contracts](/smart-contracts/contracts.md) - Contract interfaces and addresses
* [Developer Guide](/for-developers/developer-guide.md) - Integration guide

## Bridge Interface

Access the public testnet at: [**https://testnet.astralbeam.io**](https://testnet.astralbeam.io)

## Getting Help

* **Issues**: [GitHub Issues](https://github.com/make-software/astralbeam-core/issues)
* **X**: [@AstralBeam\_io](https://x.com/AstralBeam_io)
* **Telegram**: [t.me/astralbeam\_io](https://t.me/astralbeam_io)

## License

This project is licensed under the MIT License.


---

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