Registry / devops / adjust-sourcemap-loader

adjust-sourcemap-loader

library5.0.0jsnpmunverified

Webpack loader that adjusts source maps for debugging or inter-loader transformation. Currently at v5.0.0, released in 2025? Release cadence is irregular with major bumps alongside webpack majors. Key differentiator: it can be used both as a loader and as a module filename template to control output source map format (absolute, outputRelative, projectRelative, webpackProtocol, sourceRelative). Alternatives (like Webpack's built-in devtool) offer less granular control over intermediate source maps.

devops serialization

npm install adjust-sourcemap-loader

github ↗package ↗

INSTALL

IMPORT

SIG · ADJUST-SOURCEMAP-L

adjust-sourcemap-loader

devopsjavascriptv5.0.0

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 18–226 runs

build_error

glibc

node 18–226 runs

build_error

Code

Verified usage

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

default (loader)

✓ require('adjust-sourcemap-loader')

✗ import adjustSourcemap from 'adjust-sourcemap-loader'

Used in webpack config as a loader, typically via require() in CommonJS. ESM imports not typical for loader usage.

moduleFilenameTemplate

✓ const { moduleFilenameTemplate } = require('adjust-sourcemap-loader');

✗ import { moduleFilenameTemplate } from 'adjust-sourcemap-loader';

Exported as a named function. Available via CommonJS require, but ESM may also work depending on your setup.

codecs

✓ const { codecs } = require('adjust-sourcemap-loader');

Array of built-in codec objects. Rarely needed custom, but accessible if you want to inspect or extend.

Shows how to use adjust-sourcemap-loader both as a loader (with format option) and as a module filename template (for final output sources).

// webpack.config.js const path = require('path'); module.exports = { mode: 'development', entry: './src/index.js', output: { path: path.resolve(__dirname, 'dist'), filename: 'bundle.js', devtoolModuleFilenameTemplate: require('adjust-sourcemap-loader').moduleFilenameTemplate({ format: 'projectRelative' }) }, module: { rules: [ { test: /\.js$/, use: [ { loader: 'adjust-sourcemap?format=absolute' }, { loader: 'babel-loader', options: { sourceMaps: true } } ] } ] } };

Debug

Known issues

breakingVersion 5.0.0 requires Node >=12 and supports Webpack 5+ only.

fix

Upgrade Node to >=12 and ensure Webpack is version 5 or higher.

affects: >=5.0.0

breakingVersion 4.0.0 removed lodash dependency. Options must be explicitly provided; they cannot be undefined.

fix

Adjust your webpack config to provide explicit options objects where previously undefined was allowed.

affects: >=4.0.0

breakingVersion 3.0.0 removed overzealous decode check, which may cause silent failures for malformed source maps.

fix

Use the 'fail' option to ensure errors are thrown if a source-map source cannot be decoded.

affects: >=3.0.0

gotchaWhen using the loader, preceding loaders must have source maps enabled (sourceMap: true).

fix

Add ?sourceMap or sourceMaps: true to the preceding loader, e.g., babel?sourceMap.

affects: >=0

gotchaThe 'sourceRelative' format works for loader usage only, not for module filename template.

fix

Use a different format (e.g., 'projectRelative') for the module filename template.

affects: >=0

deprecatedThe 'codecs' option can be used to override built-in codecs, but doing so may break decoding unless you also include built-in codecs.

fix

If you specify custom codecs, also include the built-in codecs from require('adjust-sourcemap-loader').codecs.

affects: >=0

Errors

Common errors & fixes

Error: adjust-sourcemap-loader requires source maps to be enabled on preceding loaders

Preceding loader does not have source maps enabled.

fix

Add sourceMaps: true option to the loader that generates source maps (e.g., babel-loader).

Module parse failed: Unexpected token (1:0) You may need an appropriate loader to handle this file type.

The adjust-sourcemap-loader is not applied as a loader in the webpack config.

fix

Ensure adjust-sourcemap-loader is included in your module.rules as a loader (e.g., use: ['adjust-sourcemap?format=absolute', 'babel-loader']).

Error: Cannot find module 'adjust-sourcemap-loader'

Package not installed.

fix

Run 'npm install adjust-sourcemap-loader --save-dev'.

Upgrade

Version history

5.0.0latest on npm

Audit

Dependencies

No dependency data recorded yet.

Agent activity

54 hits · last 30 days

node

Perplexity

OpenAI (training)

Resources

githubhttps://github.com/bholloway/adjust-sourcemap-loader ↗

packagehttps://www.npmjs.com/package/adjust-sourcemap-loader ↗