solang - Solidity Compiler for Solana, Substrate, and ewasm

Welcome to Solang, a new Solidity compiler written in rust which uses llvm as the compiler backend. Solang can compile Solidity for Solana, Substrate, and ewasm. Solang is source compatible with Solidity 0.7, with some caveats due to differences in the underlying blockchain.

Solang is under active development right now, and has extensive documentation.

Simple example

First build Solang or use the container, then write the following to flipper.sol:

contract flipper {
	bool private value;

	constructor(bool initvalue) public {
		value = initvalue;
	}

	function flip() public {
		value = !value;
	}

	function get() public view returns (bool) {
		return value;
	}
}

Build for Solana

Run:

solang --target solana flipper.sol

Alternatively if you want to use the solang container, run:

docker run --rm -it -v $(pwd):/sources ghcr.io/hyperledger-labs/solang -v -o /sources --target solana /sources/flipper.sol

A file called flipper.abi and bundle.so. Now install @solana/solidity:

npm install @solana/solidity

Save the following to flipper.js:

const { Connection, LAMPORTS_PER_SOL, Keypair } = require('@solana/web3.js');
const { Contract, Program } = require('@solana/solidity');
const { readFileSync } = require('fs');

const FLIPPER_ABI = JSON.parse(readFileSync('./flipper.abi', 'utf8'));
const PROGRAM_SO = readFileSync('./bundle.so');

(async function () {
    console.log('Connecting to your local Solana node ...');
    const connection = new Connection('http://localhost:8899', 'confirmed');

    const payer = Keypair.generate();
    while (true) {
        console.log('Airdropping SOL to a new wallet ...');
        await connection.requestAirdrop(payer.publicKey, 1 * LAMPORTS_PER_SOL);
        await new Promise((resolve) => setTimeout(resolve, 1000));
        if (await connection.getBalance(payer.publicKey)) break;
    }

    const program = await Program.load(connection, payer, Keypair.generate(), PROGRAM_SO);

    console.log('Program deployment finished, deploying the flipper contract ...');

    const storageKeyPair = Keypair.generate();
    const deployRes = await program.deployContract({
        name: "flipper",
        abi: FLIPPER_ABI,
        storageKeyPair,
        constructorArgs: [true],
        space: 17,
    });

    const contract = deployRes.contract;

    const res = await contract.functions.get({ simulate: true });
    console.log('state: ' + res.result);

    await contract.functions.flip();

    const res2 = await contract.functions.get({ simulate: true });
    console.log('state: ' + res2.result);

    process.exit(0);
})();

And now run:

node flipper.js

Build for Substrate

Run:

solang --target substrate flipper.sol

Alternatively if you want to use the solang container, run:

docker run --rm -it -v $(pwd):/sources ghcr.io/hyperledger-labs/solang -v -o /sources --target substrate /sources/flipper.sol

You will have a file called flipper.contract. You can use this directly in the Polkadot UI, as if your smart contract was written using ink!.

License

Apache 2.0