@avalix/hardhat-polkavm

A Hardhat 3 plugin that compiles your Solidity contracts to PolkaVM bytecode using Parity's resolc (revive) compiler, so you can deploy them to Polkadot smart-contract chains (e.g. Asset Hub).

The official paritytech/hardhat-polkadot targets Hardhat 2. This plugin is a lightweight reimplementation for the Hardhat 3 plugin system (config + solidity hooks).

Install

npm install --save-dev @avalix/hardhat-polkavm
# or: bun add -d @avalix/hardhat-polkavm

Requires hardhat@^3.4.0.

Usage

Add the plugin and a top-level resolc block to your config. The presence of that block transparently switches every Solidity compiler from solc (EVM) to resolc (PolkaVM) — there is no per-compiler type wiring to do.

// hardhat.config.ts
import { defineConfig } from "hardhat/config";
import hardhatPolkaVM from "@avalix/hardhat-polkavm";

export default defineConfig({
  plugins: [hardhatPolkaVM],
  solidity: "0.8.29",
  resolc: {
    compilerSource: "npm",
    optimizer: { enabled: true, runs: 200 },
  },
});

Then compile as usual:

npx hardhat compile

The emitted artifacts contain PolkaVM bytecode. Remove the resolc block to go back to a normal EVM build.

Compiler sources

| compilerSource | How it works | When to use | | --- | --- | --- | | "npm" (default) | Uses the self-contained @parity/resolc package, which bundles solc. No downloads, works on every platform/arch. | The simplest, most portable option. | | "binary" | Downloads the native resolc release from GitHub and drives it over --standard-json, calling Hardhat's solc via --solc. Faster, but native binaries exist only for macOS, Linux x64 and Windows x64. | Larger projects where compile speed matters. |

Configuration reference

resolc: {
  // "npm" (default) | "binary"
  compilerSource: "npm",

  // revive/resolc release for "binary" mode (default: "1.2.0")
  version: "1.2.0",

  optimizer: {
    enabled: true,   // default: true
    runs: 200,       // default: 200
    mode: "3",       // "0" | "1" | "2" | "3" | "s" | "z" (optional)
    fallbackOz: true // retry with -Oz if the bytecode is too large (optional)
  },

  // "binary" mode only — skip the download / use your own toolchain:
  resolcPath: "/path/to/resolc",
  solcPath: "/path/to/solc",
}

How it works

Hardhat 3 exposes a solidity hook with two extension points the plugin uses:

• getCompiler — returns a custom Compiler for type: "resolc" that produces PolkaVM bytecode (instead of solc's EVM bytecode).
• downloadCompilers — fetches the native resolc binary in "binary" mode.

A config hook resolves the resolc block and rewrites the resolved Solidity config so each compiler uses type: "resolc".

License

MIT