Registry / devops / babel-plugin-import-map

babel-plugin-import-map

library1.0.0jsnpmunverified

A Babel plugin to apply import map mappings to ECMAScript modules ahead of time. Current stable version is 1.0.0. This plugin allows transforming bare import specifiers (e.g., 'lit-html') to absolute URLs (e.g., CDN URLs) at build time, based on one or more import map files. It supports loading import maps from JSON files or plain objects, and can merge multiple maps. Unlike runtime import map polyfills, this works purely at the build level, making it suitable for production bundles. Once loaded, the plugin replaces import specifiers statically during Babel transpilation.

devops http-networking

npm install babel-plugin-import-map

github ↗package ↗

INSTALL

IMPORT

SIG · BABEL-PLUGIN-IMPOR

babel-plugin-import-map

devopsjavascriptv1.0.0

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.

plugin

✓ import * as plugin from 'babel-plugin-import-map'

✗ import plugin from 'babel-plugin-import-map'

This package uses a namespace import; default import does not work.

plugin.load()

✓ plugin.load('./import-map.json')

✗ plugin.load({imports: {'lit-html': 'https://cdn.example.com/lit-html.js'}})

You can pass a string path or an object; wrong example is actually correct, but a common mistake is to forget the './' relative path.

plugin.plugin()

✓ plugin.plugin()

✗ plugin()

The plugin function is a method on the imported namespace, not the default export itself.

plugin.clear()

✓ plugin.clear()

✗ plugin.clear

clear() is a method that must be called; omitting parentheses is a common mistake.

Shows how to load an import map file and apply the plugin in a Babel configuration to transform bare ESM imports.

import * as plugin from 'babel-plugin-import-map'; plugin.load('import-map.json'); export default { presets: [ ['@babel/preset-env', { modules: false }] ], plugins: [ plugin.plugin() ] };

Debug

Known issues

gotchaImport specifiers already mapped are replaced; last mapping in array wins.

fix

Ensure correct order when passing multiple maps.

affects: >=1.0.0

gotchaThe plugin does not validate import map JSON; malformed maps cause runtime errors.

fix

Validate import map JSON before loading.

affects: >=1.0.0

gotchaThe plugin only transforms static import/export statements, not dynamic import().

fix

Use a separate plugin or runtime polyfill for dynamic imports.

affects: >=1.0.0

Errors

Common errors & fixes

TypeError: plugin.load is not a function

Using default import instead of namespace import.

fix

import * as plugin from 'babel-plugin-import-map'

Error: Could not find import map file: source/import-map.json

File path is relative to current working directory, not Babel config location.

fix

Use absolute path or path relative to process.cwd()

TypeError: Cannot read properties of undefined (reading 'imports')

Passing an object without 'imports' key or empty object.

fix

Ensure import map object has 'imports' key.

Upgrade

Version history

1.0.0latest on npm

Audit

Dependencies

No dependency data recorded yet.

Agent activity

17 hits · last 30 days

node

OpenAI (training)

Resources

githubhttps://github.com/trygve-lie/babel-plugin-import-map ↗

packagehttps://www.npmjs.com/package/babel-plugin-import-map ↗