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The Developer Toolkit for Polkadot

Build and submit any substrate extrinsic visually, write Solidity smart contracts, and deploy to Polkadot Hub - all from your browser.

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Relaycode Demo — bi-directional extrinsic builder
New on Polkadot Hub

Write, Compile, Deploy - All in Your Browser

The first native smart contract IDE for Polkadot Hub. Write Solidity, compile to PolkaVM, and deploy with Polkadot wallets - no CLI, no MetaMask, no fragmented toolchain.

relaycode.org/studio
Files
PolkaSwap.sol
Router.sol
IPool.sol
+ New File
PolkaSwap.sol
Router.sol
IPool.sol
1// SPDX-License-Identifier: MIT
2pragma solidity ^0.8.20;
3
4import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
5import "@openzeppelin/contracts/access/Ownable.sol";
6
7contract PolkaSwap is ERC20, Ownable {
8 mapping(address => uint256) public liquidity;
9 uint256 public totalLiquidity;
10
11 constructor() ERC20("PolkaSwap", "PSWAP") Ownable(msg.sender) {
12 _mint(msg.sender, 1000000 * 10 ** decimals());
13 }
14
15 function addLiquidity() external payable {
16 liquidity[msg.sender] += msg.value;
17 totalLiquidity += msg.value;
18 }
19}
OutputCompiled(PolkaSwap.sol:PolkaSwap)
Compiled successfully (PolkaSwap.sol:PolkaSwap)
⚠Warning: SPDX license identifier not provided in source file
Compile
EVM
PVM (Polkadot)
Compile
PolkaSwap
9,265 bytes · 52 ABI entries
Compiled
Deploy
admin address
0x...
Deploy
Westend Asset Hub
PVM
Compiled
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Developers
💙 Relaycode

We created Relaycode to solve our own issues around complex chain data and encoding in Polkadot. Our goal is to let users and developers focus on building instead of dealing with the intricacies of Polkadot.

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Our Extrinsic Builder is live on Polkadot

Seriously – it's easier than DeFi on Ethereum.

relaycode.org/builder
Relaycode Extrinsic Builder

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3

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Built for the Polkadot ecosystem

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