Why

ESM is the future. No bundling, no bullsh*t.

esimport is fast 🔥, simpel 🧃, secure 🏴‍☠️, and backwards compatible ☎️.

| | esimport | esm.sh | jsDelivr | | ------------------------------- | -------- | ------ | -------- | | private package support | ✅ | ❌ | ❌ | | offline development | ✅ | ⚠️ | ❌ | | dependabot support | ✅ | ❌ | ❌ | | integrity support | ✅ | ❌ | ❌ | | supply chain attacks protection | ✅ | ❌ | ❌ | | highly efficient client caching | ✅ | ✅ | ✅ |

Usage

# esimport <package-root> <output-dir> [--watch,--serve,--path-prefix,--verbose,--help]
npx esimport . ./public/static/  --serve

That's it!

Output

Let's assume we have a project with Lit and a custom component defined via imports. After running esimport we have the following output:

# the folder containing browser ready ESM files
$ tree -d out
out
├── src
└── node_modules
    ├── lit
    │   ├── decorators
    │   └── directives

# a fully resolved importmap with sha512 hashes
$ jq '.' out/importmap.json
{
  "imports": {
    "#js/components/myWidget": "src/js/components/myWidget-KWLRK5KY.js",
    "lit": "node_modules/lit/index-W3JFEEGS.js",
    "lit/async-directive.js": "node_modules/lit/async-directive-C4RAQ6VS.js",
    "lit/decorators.js": "node_modules/lit/decorators-RLPUYE5L.js",
    // …
  },
  "integrity": {
    "src/js/components/myWidget-KWLRK5KY.js": "sha512-AcfJS2+aGBtNqX5ZPJFJPySC+bmDKC7I64mExuSJM+qnWmSrahd/a94XnsdpyeQWry9DaivErfhxu8avQ3Tiow==",
    "node_modules/lit/index-W3JFEEGS.js": "sha512-CxSTqZXCqTYvL7K0JJtFT5NJdVYp8fJnjXR6pVt/IcC3VAcr+J5EtQsgLR9Q30C0SJD/QmeX+cd6C4T8cbdihg==",
    "node_modules/lit/async-directive-C4RAQ6VS.js": "sha512-bftcjSsligJFPy44umcVoBR8A5Gnaosp6uLUett18w9zNaqfC6BgSFzIErq0Npb1tNUPwwCQckIMjKFyYKAGBg==",
    "node_modules/lit/decorators-RLPUYE5L.js": "sha512-zDE+J+OhoRU8Lle7jSxZVojj8JoWZuqWf2QzvFfF2CWgk4lGycTj8c7rZ3p24OLVDAhe/vUTWsb3gbt5m8JLgw==",
    // …
  }
}