# @web/dev-server-legacy

> Plugin for legacy browsers in @web/dev-server

Latest version **3.0.0** (published 2026-07-07) · MIT license · 0 weekly downloads

## Install

```sh
npm install @web/dev-server-legacy
pnpm add @web/dev-server-legacy
yarn add @web/dev-server-legacy
bun add @web/dev-server-legacy
```

## Health

**Score 70/100 (B)** — status: active.

Positive: has types; esm support; no vulnerabilities; has provenance; recently updated; high maintenance score.

Warnings: low downloads.

## Facts

| | |
|---|---|
| Version | 3.0.0 |
| Published | 2026-07-07 |
| First published | 2020-07-15 |
| Weekly downloads | 0 |
| License | MIT |
| TypeScript types | bundled |
| Module format | ESM + CommonJS |
| Node | >=22.0.0 |
| Dependencies | 16 |
| Unpacked size | 49.6 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| Provenance | attested (GitHub Actions) |
| GitHub stars | 2452 |
| Author | modern-web |
| Maintainers | d4kmor, passle, jorenbroekema, bennyp, larsdenbakker, westbrook, modern-web |
| Keywords | web, dev, server, test, runner, testrunner, typescript, jsx, compile, transform |

## Links

- npm: https://www.npmjs.com/package/@web/dev-server-legacy
- Repository: https://github.com/modernweb-dev/web
- Homepage: https://github.com/modernweb-dev/web/tree/master/packages/dev-server-legacy
- Issues: https://github.com/modernweb-dev/web/issues
- npm.io page: https://npm.io/package/@web/dev-server-legacy

## Dependencies (16)

- [parse5](https://npm.io/package/parse5.md) ^6.0.1
- [valid-url](https://npm.io/package/valid-url.md) ^1.0.9
- [@babel/core](https://npm.io/package/@babel/core.md) ^7.12.10
- [caniuse-api](https://npm.io/package/caniuse-api.md) ^3.0.0
- [browserslist](https://npm.io/package/browserslist.md) ^4.16.0
- [@babel/preset-env](https://npm.io/package/@babel/preset-env.md) ^7.12.11
- [@web/dev-server-core](https://npm.io/package/@web/dev-server-core.md) ^1.0.0
- [@web/polyfills-loader](https://npm.io/package/@web/polyfills-loader.md) ^3.0.0
- [browserslist-useragent](https://npm.io/package/browserslist-useragent.md) ^4.0.0
- [@babel/plugin-syntax-import-meta](https://npm.io/package/@babel/plugin-syntax-import-meta.md) ^7.10.4
- [@babel/plugin-syntax-dynamic-import](https://npm.io/package/@babel/plugin-syntax-dynamic-import.md) ^7.8.3
- [@babel/plugin-proposal-dynamic-import](https://npm.io/package/@babel/plugin-proposal-dynamic-import.md) ^7.12.1
- [@babel/plugin-syntax-class-properties](https://npm.io/package/@babel/plugin-syntax-class-properties.md) ^7.12.1
- [@babel/plugin-syntax-numeric-separator](https://npm.io/package/@babel/plugin-syntax-numeric-separator.md) ^7.10.4
- [@babel/plugin-transform-modules-systemjs](https://npm.io/package/@babel/plugin-transform-modules-systemjs.md) ^7.12.1
- [@babel/plugin-transform-template-literals](https://npm.io/package/@babel/plugin-transform-template-literals.md) ^7.12.1

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## Recent versions

- 3.0.0 (latest) — 2026-07-07
- 0.0.0-canary-20240219104536 (canary) — 2024-02-19
- 2.1.1 — 2024-05-12
- 0.0.0-canary-20240219104126 — 2024-02-19
- 0.0.0-canary-20240212171943 — 2024-02-12
- 0.0.0-canary-20240105101412 — 2024-01-05
- 0.0.0-canary-20240105095248 — 2024-01-05
- 0.0.0-canary-20240105093823 — 2024-01-05
- 0.0.0-canary-20240105092607 — 2024-01-05
- 0.0.0-canary-20240105091725 — 2024-01-05
- 0.0.0-canary-20231122093600 — 2023-11-22
- 2.1.0 — 2023-11-01
- 2.0.3 — 2023-10-19
- 2.0.2 — 2023-10-17
- 2.0.1 — 2023-07-19
- … 24 more at https://npm.io/package/@web/dev-server-legacy/versions

## README

# Dev Server Legacy

Plugin for using the dev server or test runner on legacy browsers, for example on Internet Explorer 11 which does not support modules.

See [our website](https://modern-web.dev/docs/dev-server/plugins/legacy/) for full documentation.

---
_Source: https://npm.io/package/@web/dev-server-legacy · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._