Registry / devops / babel-preset-njs

babel-preset-njs

library0.7.0jsnpmunverified

A Babel preset for transforming modern JavaScript (up to ES2021) into code compatible with njs (NGINX JavaScript). Current stable version is 0.7.0, targeting njs ≥ 0.7.0, with peer dependency on @babel/core ^7.0.0-0. Key differentiator: provides a curated set of Babel plugins for features not yet supported by njs (e.g., classes, for-of, object rest/spread), while skipping transformations for features njs already supports (e.g., arrow functions, block scoping, destructuring). Ideal for developers writing njs scripts with modern JS syntax.

devops web-framework

npm install babel-preset-njs

github ↗package ↗

INSTALL

IMPORT

SIG · BABEL-PRESET-NJS

babel-preset-njs

devopsjavascriptv0.7.0

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.

babelPresetNjs

✓ import babelPresetNjs from 'babel-preset-njs'

✗ const babelPresetNjs = require('babel-preset-njs')

ESM import; can also be used with require in CJS

babel-preset-njs (preset name string)

✓ module.exports = { presets: ['babel-preset-njs'] }

✗ module.exports = { presets: [require('babel-preset-njs')] }

In Babel config, reference the preset by its name string, not by directly requiring it.

babel.config.js (using preset via string)

✓ { "presets": ["babel-preset-njs"] }

✗ { "presets": ["@babel/preset-njs"] }

Do not prefix with @babel/. The preset name is exactly 'babel-preset-njs'.

Shows installation, Babel config, and a simple njs script using for-of and object spread, both of which are transformed by the preset.

// Install: npm install --save-dev @babel/core babel-preset-njs // Then create babel.config.js: module.exports = { presets: ['babel-preset-njs'] }; // Now write your njs script (src/index.js): const arr = [1, 2, 3]; const obj = { a: 1, b: 2 }; const spread = { ...obj, c: 3 }; for (const x of arr) { ngx.log(ngx.INFO, x); } // Run: npx babel src/index.js --out-dir dist // Result will be compatible with njs (e.g., for-of transpiled, object spread transformed).

Debug

Known issues

breakingVersion 0.7.0 requires njs ≥ 0.7.0. Older versions of njs may not work.

fix

Upgrade njs to at least 0.7.0 or use an older version of the preset (0.2.1 max).

affects: >=0.7.0 <0.8.0

gotchaThe preset does NOT transform dynamic import() or generators (yield) as njs does not support them. These will fail at runtime.

fix

Avoid using dynamic imports and generators in njs code, or provide your own custom plugin.

affects: >=0.1.0

deprecatedSome plugins included may become unnecessary as njs evolves. Check compatibility table before upgrading.

fix

Review the plugin list in the preset's README to see which features are now natively supported.

affects: >=0.1.0

Errors

Common errors & fixes

ReferenceError: require is not defined in ES module scope

Using require() to load the preset in an ES module environment.

fix

Use import babelPresetNjs from 'babel-preset-njs' or use require in a CommonJS context.

SyntaxError: Unexpected token '.' (when using optional chaining)

Optional chaining (?.) is not yet supported by njs and not included in the preset's plugins.

fix

Avoid optional chaining; use if statements or add @babel/plugin-proposal-optional-chaining manually.

Error: Plugin/Preset files are not allowed to export objects, only functions

Using an older version of the preset that exports an object instead of a function.

fix

Update to babel-preset-njs@0.7.0 and ensure @babel/core is version 7+.

Upgrade

Version history

0.7.0latest on npm

Audit

Dependencies

@babel/corerequiredPeer dependency required for Babel integration

Agent activity

9 hits · last 30 days

node

OpenAI (training)

Resources

githubhttps://github.com/jirutka/babel-preset-njs ↗

packagehttps://www.npmjs.com/package/babel-preset-njs ↗