solc-js

library1.0.1jsnpmunverified

solc-js v1.0.1 is a cross-browser JavaScript bindings for the Solidity compiler, using Emscripten-compiled solc binaries from the solc-bin repository. It is designed as a smaller and faster alternative to the solc package for browser-only environments, while solc or solc-native are recommended for Node.js. It provides an async API to fetch compiler versions, compile Solidity source code, and resolve imports. It has a moderate release cadence and is maintained as part of the ethereum-play project on GitHub.

devops serialization

npm install solc-js

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · SOLC-JS

solc-js

devopsjavascriptv1.0.1

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

default

✓ import solcjs from 'solc-js'

✗ const solcjs = require('solc-js')

solc-js is ESM-only; CommonJS require will fail. Use dynamic import in Node.js if needed.

types

✓ import type { SolcJS, CompilerOutput } from 'solc-js'

✗ None

TypeScript types are exported but minimal; consider declaring own types for compiler output.

versions

✓ const { versions } = await import('solc-js')

✗ const { versions } = require('solc-js')

CommonJS require does not work; use dynamic import or ESM.

version2url

✓ const { version2url } = await import('solc-js')

✗ const version2url = solcjs.version2url

Named export, not a method on the default export.

Import solc-js, fetch available versions, load a specific compiler, and compile a simple Solidity contract.

import solcjs, { versions } from 'solc-js'; async function compile() { const allVersions = await versions(); console.log('Available releases:', allVersions.releases); const version = allVersions.releases[0] || 'v0.8.20-stable-2023.06.13'; const compiler = await solcjs(version); const source = ` pragma solidity ^0.8.0; contract HelloWorld { string public greeting = "Hello, World!"; } `; const output = await compiler(source); console.log('Compiled bytecode:', output.bytecode); } compile().catch(console.error);

Debug

Known issues

breakingsolc-js v1.0.0+ is ESM-only, breaking CommonJS require.

fix

Use ESM imports (`import solcjs from 'solc-js'`) or dynamic import in Node.js.

affects: >=1.0.0

deprecatedThe default export `solcjs(version)` now returns a compiler function, not a compiler object with `.version`.

fix

Access `.version` from the `solcjs` module itself: `const { version } = await solcjs(version);` is incorrect; use `const compiler = await solcjs(version);` and check compiler.version if needed.

affects: >=1.0.0

gotchaWhen calling `solcjs()` without version, it fetches the latest release, which may be a nightly build.

fix

Always specify a version string to avoid unexpected compiler versions. Use `versions().releases[0]` for stable.

affects: all

gotchaUsing `solcjs` in Node.js is not recommended; it may be slower and have different behavior than the native `solc` package.

fix

For Node.js, use `solc` or `solc-native` instead.

affects: all

Errors

Common errors & fixes

require is not defined in ES module scope

Trying to use CommonJS require with solc-js, which is ESM-only in v1.0+.

fix

Switch to ESM imports: `import solcjs from 'solc-js';`

TypeError: solcjs is not a function

Using `require('solc-js')` without .default (CommonJS interop) with older bundlers.

fix

Use `const solcjs = require('solc-js').default;` or upgrade to ESM.

Uncaught TypeError: compiler is not a function

Calling `await solcjs(version)` and then calling `compiler(source)` on the result, but `solcjs` itself is the compiler (no need to call twice).

fix

Use `const compiler = await solcjs(version); const output = await compiler(source);` correctly.

Upgrade

Version history

1.0.1latest on npm

Audit

Dependencies

solc-resolveroptionalRecommended for automatic import resolution when compiling projects with external file imports.

Agent activity

6 hits · last 30 days

node

Resources

githubhttps://github.com/ethereum-play/solc-js ↗

packagehttps://www.npmjs.com/package/solc-js ↗

homepagehttps://ethereum.org ↗