locutus

Locutus

All your standard libraries will be assimilated into our JavaScript TypeScript collective. Resistance is futile.

Locutus is ~500 TypeScript implementations of standard library functions from PHP, Go, Python, Ruby, C, and more. Each function is individually importable and tree-shakeable.

Most of these started as rainy Sunday afternoon puzzles. Some are genuinely useful. Some are just fun to write. All of them are a way to learn how different languages solve the same problems.

Scope

Locutus ports function behavior, not foreign runtime baggage. We reimplement standard-library semantics in TypeScript, but keep API boundaries JavaScript-native.

That means we do not recreate alien language data structures or object models in Locutus APIs (for example: Go slices/maps, Python tuples/bytes, Ruby symbols, C structs/pointers, Perl refs).

Historic exception: for PHP compatibility, plain JS objects may be treated as associative arrays when locutus.objectsAsArrays is enabled.

Example: a Go date-formatting port in Locutus should accept a JavaScript Date and return a string, not a custom Go time.Time object.

Install

npm install locutus

Locutus uses pragmatic versioning: patch is the default even for function-level parity fixes; see CONTRIBUTING.md#versioning for exact bump criteria.

Use

import { sprintf } from 'locutus/php/strings/sprintf'

const effectiveness = 'futile'
console.log(sprintf('Resistance is %s', effectiveness))
// Resistance is futile

import { Contains } from 'locutus/golang/strings/Contains'

console.log(Contains('Locutus', 'cut'))
// true

Bundle Size

For bundle-sensitive browser builds, prefer per-function deep imports over category index imports.

Good:

import { sprintf } from 'locutus/php/strings/sprintf'

Avoid in browser bundles:

import { sprintf } from 'locutus/php/strings/index'

Why:

• deep imports only pull the function you asked for and its real dependencies
• category index imports can force bundlers to traverse many unrelated exports in the same namespace
• this matters most in prebundled UMD/browser artifacts where downstream tree-shaking cannot recover later

If you are publishing your own browser bundle on top of Locutus, treat deep imports as the default.

Browser Compatibility (Copy-Paste Snippets)

Code shown on function pages (Module JS / Standalone JS) targets:

• baseline widely available with downstream

Package runtime targets:

• Node: engines.node >= 22
• Published dist output (dist/ CommonJS + dist/esm ESM): ES2022

If your application targets older browsers, treat Locutus snippets like normal application code:

• transpile to your target (for example with TypeScript, Babel, SWC, or esbuild)
• add required polyfills for missing APIs in your environment
• validate with your own Browserslist target and browser test matrix

Locutus does not inject polyfills into copy-paste snippets by default.

Development

Some guidelines and instructions can be found in CONTRIBUTING.md

Quick commands:

• yarn check - format + lint + test
• yarn test:parity - cross-language verification
• yarn test - full test suite
• yarn lint - Biome check
• yarn fix:biome - auto-fix

License

MIT, except for src/php/bc/ and src/php/_helpers/_bc.js which are LGPL-2.1 (derived from PHP's bcmath/Libbcmath). See LICENSE for details.

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