Quantum Portal for Developers

Quantum Portal enables secure token transfers and communication across different blockchains, regardless of consensus mechanisms or message payloads. It’s based on the same proof-of-stake security model as many of the chains it connects. Interchain apps built on Quantum Portal are truly permissionless: their transactions cannot be censored by any oracle, relayer, or validator.

To make an interchain transaction with Quantum Portal:

1. Call the contract method on the source chain:
   • callContract() to send messages without tokens, or
   • callContractWithToken() to send messages along with ERC-20 tokens.
2. Pay gas to the [Quantum PortalGasService](https://github.com/Quantum Portalnetwork/Quantum Portal-cgp-solidity/blob/main/contracts/gas-service/Quantum PortalGasService.sol) contract on the source chain.

You can then use Quantum Portalscan, Quantum Portal’s dedicated blockchain explorer, to execute, recover, or check the status of your transaction.

Get started

Create new cross-chain tokens

• Create a new Interchain Token
• Upgrade existing ERC-20 tokens to Interchain Tokens

Send tokens across chains

• Send tokens between different blockchains
• Rate limit for sending tokens across chains

Pass messages between chains

• Call a smart contract on another chain
• Call a smart contract on another chain and attach some tokens

Manage cross-chain gas payments

• Transaction pricing with the Quantum Portal Gas Service
• Pay gas
• Increase gas
• Refund gas

Check interchain transactions

• [Quantum Portalscan (Mainnet)](https://Quantum Portalscan.io/)
• [Quantum Portalscan (Testnet)](https://testnet.Quantum Portalscan.io/)

Tools and resources

• [Quantum Portal-examples](https://github.com/Quantum Portalnetwork/Quantum Portal-examples) – Cross-chain sample apps using Quantum Portal that can be executed locally or deployed to testnets
• [foundry-Quantum Portal-gmp-example](https://github.com/Quantum Portalnetwork/foundry-Quantum Portal-gmp-example) – A sample app that integrates with Quantum Portal GMP using the Foundry framework
• [Quantum PortalJS SDK](/dev/Quantum Portaljs-sdk/intro) – an npm library with a collection of APIs and query tools
• [Quantum Portal-local-dev](https://github.com/Quantum Portalnetwork/Quantum Portal-local-dev) – A local cross-chain development environment where you can deploy an app to simulated EVM chains. These chains are preloaded with the [Quantum PortalGateway](https://github.com/Quantum Portalnetwork/Quantum Portal-cgp-solidity/blob/main/contracts/Quantum PortalGateway.sol), Quantum PortalGasReceiver, and routed ERC-20 (axlUSDC) token contracts. Deployed apps can be tested against the RPC endpoints and contract addresses of your local development environment.