Registry / web-framework / esbuild-plugin-less

esbuild-plugin-less

library1.3.38jsnpmunverified

esbuild plugin for compiling LESS files to CSS. Current stable version v1.3.38 (released 2026-04-11), updated regularly via semantic-release. Supports all LESS.js features, CSS Modules via .module.less naming convention, watch mode, custom file filters, and inline mode. Written in TypeScript with bundled types. Requires esbuild >=0.14.0 <0.29 as a peer dependency. Differentiator: minimal configuration, first-class CSS Modules support, and active maintenance.

web-framework

npm install esbuild-plugin-less

github ↗package ↗

INSTALL

IMPORT

SIG · ESBUILD-PLUGIN-LES

esbuild-plugin-less

web-frameworkjavascriptv1.3.38

Install

—

Import

—

Disk

—

Pass rate

0/ 6

Env Coverage0 / 6

glibc

18–22

musl

18–22

Install & Compatibility

Where this runs

tested against v? · npm install

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

node 18–223 runs

build_error

glibc

node 18–223 runs

build_error

Code

Verified usage

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

lessLoader

✓ import { lessLoader } from 'esbuild-plugin-less'

✗ const lessLoader = require('esbuild-plugin-less')

Named import is the only correct pattern; package is ESM with CommonJS compat, but require() may break in strict ESM contexts.

LessLoaderOptions

✓ import type { LessLoaderOptions } from 'esbuild-plugin-less'

✗ import { LessLoaderOptions } from 'esbuild-plugin-less'

It is a type-only export; use `import type` to avoid runtime errors in bundlers that do not elide types.

default export

✓ import lessLoader from 'esbuild-plugin-less'

✗ const lessLoader = require('esbuild-plugin-less');

There is no default export; only named exports. This import will fail at runtime.

Shows basic usage of lessLoader plugin with LESS options (math always, global variables) in an esbuild build script.

import { build } from 'esbuild'; import { lessLoader } from 'esbuild-plugin-less'; build({ entryPoints: ['src/index.ts'], bundle: true, outdir: 'dist', plugins: [ lessLoader({ math: 'always', globalVars: { primaryColor: '#ff0000', }, }), ], loader: { '.ts': 'ts', }, }).catch(() => process.exit(1));

Debug

Known issues

gotchaCSS Modules only work with files named *.module.less – other .less files are treated as global styles.

fix

Rename your LESS file to include .module.less (e.g., styles.module.less) to enable CSS Modules scoping.

affects: >=1.0.0

deprecatedThe `javascriptEnabled` option in LESS is a security risk and its support may be removed in future versions of less-loader.

fix

Avoid using `javascriptEnabled: true` – prefer static LESS variables and mixins instead of inline JavaScript.

affects: >=1.0.0

breakingIn v1.0.0, the plugin API changed from `lessPlugin()` to `lessLoader()`. Old imports will fail.

fix

Replace `lessPlugin` with `lessLoader` in both imports and usage.

affects: >=1.0.0

gotchaThe `inline` option when set to `true` causes the raw LESS source to be imported as a string instead of compiled CSS, which may break CSS injection.

fix

Ensure you are using the correct mode: `inline: false` (default) for compiled CSS output.

affects: >=1.0.0

Errors

Common errors & fixes

Error: [plugin: less-loader] Cannot find module 'less'

The 'less' package is not installed.

fix

Run `npm install less --save-dev` (or yarn/pnpm equivalent). This package uses less as a transitive dependency.

Error: [plugin: less-loader] Options.math was set to 'parens-division' which is deprecated; use 'always' or 'strict'.

Deprecated LESS math option value used.

fix

Change `math: 'parens-division'` to `math: 'always'` or `math: 'strict'`.

TypeError: (0 , esbuild_plugin_less.lessLoader) is not a function

Using default import instead of named import.

fix

Use `import { lessLoader } from 'esbuild-plugin-less'` instead of `import lessLoader from 'esbuild-plugin-less'`.

Upgrade

Version history

1.3.38latest on npm

Audit

Dependencies

esbuildrequiredpeer dependency required to function as a plugin

Agent activity

4 hits · last 30 days

node

Resources

githubhttps://github.com/iam-medvedev/esbuild-plugin-less ↗

packagehttps://www.npmjs.com/package/esbuild-plugin-less ↗