Unwanted WebAssembly binaries persist after installing sharp in Next.js projects using Tailwind or ESLint

[foobar-star]

Possible bug

When sharp is used in a project that also contains specific dependencies like @tailwindcss/postcss@4.1.14 and eslint-config-next@15.5.4, it causes sharp to incorrectly detect that it is in an Emscripten environment. This leads to sharp attempting to build WebAssembly (WA) binaries during npm install, causing extraneous dependencies and confusion for users.

Furthermore, post-install scripts from napi-rs make it impossible to remove the WebAssembly binaries unless the sharp package and its node modules are completely removed from the project and dependencies are reinstalled.

This issue was first identified in a Next.js issue here [https://github.com/vercel/next.js/issues/84450#] and brought up to the maintainers of next.js where sharp was pulled in as a transitive dependency, even though there was no intention of using sharp directly.

Is this a possible bug in a feature of sharp, unrelated to installation?

• Running npm install sharp completes without error.
• Running node -e "require('sharp')" completes without error.

Are you using the latest version of sharp?

• I am using the latest version of sharp as reported by npm view sharp dist-tags.latest.

If you cannot confirm this, please upgrade to the latest version and try again before opening an issue.

If you are using another package which depends on a version of sharp that is not the latest, please open an issue against that package instead.

Does this problem relate to file caching?

The default behavior of libvips is to cache input files, which can lead to EBUSY or EPERM errors on Windows.
Use [sharp.cache(false)](https://sharp.pixelplumbing.com/api-utility#cache) to switch this feature off.

• Adding sharp.cache(false) does not fix this problem.

Does this problem relate to images appearing to have been rotated by 90 degrees?

Images that contain EXIF Orientation metadata are not auto-oriented. By default, EXIF metadata is removed.

• To auto-orient pixel values use the parameter-less [rotate()](https://sharp.pixelplumbing.com/api-operation#rotate) operation.

• To retain EXIF Orientation use [keepExif()](https://sharp.pixelplumbing.com/api-output#keepexif).

• Using rotate() or keepExif() does not fix this problem.

What are the steps to reproduce?

1. Install Node.js project with eslint-config-next@15.5.4 or @tailwindcss/postcss@4.1.14.

2. Install sharp either directly or as a transitive dependency (via next.js).

3. install next.js via npx create-next-app and select tailwind or eslint.

4. then run npm ls
   Alternatively:

5. Install a Node.js project with sharp and @tailwindcss/postcss@4.1.14.

6. Install a Node.js project with sharp, @tailwindcss/postcss@4.1.14, and eslint-config-next@15.5.4`

7. then run npm ls

What is the expected behavior?

A clean installation of dependencies without the extraneous dependencies or unneeded WebAssembly binaries or post-install scripts altering the project.

Please provide a minimal, standalone code sample, without other dependencies, that demonstrates this problem

See here: vercel/next.js#84450

Please provide sample image(s) that help explain this problem

There is no need for images for this issue to arise.

[lovell]

The linked issue mentions npm version 10. Are you able to reproduce using the latest version 11?

[foobar-star]

Yes the issue is still transpiring with version 11 of npm as well.

[lovell]

$ node -v
v24.10.0

$ npm -v
11.6.1

$ cat package.json 
{
  "dependencies": {
    "@tailwindcss/postcss": "^4.1.14",
    "sharp": "^0.34.4"
  }
}

$ npm install

added 76 packages, and audited 77 packages in 2s

38 packages are looking for funding
  run `npm fund` for details

found 0 vulnerabilities

$ npm ls
├── @tailwindcss/postcss@4.1.14
└── sharp@0.34.4

$ ls -w1 node_modules/@img
colour
sharp-libvips-linux-x64
sharp-linux-x64

$ npm ls --all
├─┬ @tailwindcss/postcss@4.1.14
│ ├── @alloc/quick-lru@5.2.0
│ ├─┬ @tailwindcss/node@4.1.14
│ │ ├─┬ @jridgewell/remapping@2.3.5
│ │ │ ├─┬ @jridgewell/gen-mapping@0.3.13
│ │ │ │ ├── @jridgewell/sourcemap-codec@1.5.5 deduped
│ │ │ │ └── @jridgewell/trace-mapping@0.3.31 deduped
│ │ │ └─┬ @jridgewell/trace-mapping@0.3.31
│ │ │   ├── @jridgewell/resolve-uri@3.1.2
│ │ │   └── @jridgewell/sourcemap-codec@1.5.5 deduped
│ │ ├─┬ enhanced-resolve@5.18.3
│ │ │ ├── graceful-fs@4.2.11
│ │ │ └── tapable@2.3.0
│ │ ├── jiti@2.6.1
│ │ ├─┬ lightningcss@1.30.1
│ │ │ ├── detect-libc@2.1.2 deduped
│ │ │ ├── lightningcss-darwin-arm64@1.30.1
│ │ │ ├── lightningcss-darwin-x64@1.30.1
│ │ │ ├── lightningcss-freebsd-x64@1.30.1
│ │ │ ├── lightningcss-linux-arm-gnueabihf@1.30.1
│ │ │ ├── lightningcss-linux-arm64-gnu@1.30.1
│ │ │ ├── lightningcss-linux-arm64-musl@1.30.1
│ │ │ ├── lightningcss-linux-x64-gnu@1.30.1
│ │ │ ├── lightningcss-linux-x64-musl@1.30.1
│ │ │ ├── lightningcss-win32-arm64-msvc@1.30.1
│ │ │ └── lightningcss-win32-x64-msvc@1.30.1
│ │ ├─┬ magic-string@0.30.19
│ │ │ └── @jridgewell/sourcemap-codec@1.5.5
│ │ ├── source-map-js@1.2.1
│ │ └── tailwindcss@4.1.14 deduped
│ ├─┬ @tailwindcss/oxide@4.1.14
│ │ ├── @tailwindcss/oxide-android-arm64@4.1.14
│ │ ├── @tailwindcss/oxide-darwin-arm64@4.1.14
│ │ ├── @tailwindcss/oxide-darwin-x64@4.1.14
│ │ ├── @tailwindcss/oxide-freebsd-x64@4.1.14
│ │ ├── @tailwindcss/oxide-linux-arm-gnueabihf@4.1.14
│ │ ├── @tailwindcss/oxide-linux-arm64-gnu@4.1.14
│ │ ├── @tailwindcss/oxide-linux-arm64-musl@4.1.14
│ │ ├── @tailwindcss/oxide-linux-x64-gnu@4.1.14
│ │ ├── @tailwindcss/oxide-linux-x64-musl@4.1.14
│ │ ├─┬ @tailwindcss/oxide-wasm32-wasi@4.1.14
│ │ │ ├── UNMET DEPENDENCY @emnapi/core@^1.5.0
│ │ │ ├── @emnapi/runtime@1.5.0 deduped
│ │ │ ├── UNMET DEPENDENCY @emnapi/wasi-threads@^1.1.0
│ │ │ ├── UNMET DEPENDENCY @napi-rs/wasm-runtime@^1.0.5
│ │ │ ├── UNMET DEPENDENCY @tybys/wasm-util@^0.10.1
│ │ │ └── tslib@2.8.1
│ │ ├── @tailwindcss/oxide-win32-arm64-msvc@4.1.14
│ │ ├── @tailwindcss/oxide-win32-x64-msvc@4.1.14
│ │ ├── detect-libc@2.1.2 deduped
│ │ └─┬ tar@7.5.1
│ │   ├─┬ @isaacs/fs-minipass@4.0.1
│ │   │ └── minipass@7.1.2 deduped
│ │   ├── chownr@3.0.0
│ │   ├── minipass@7.1.2
│ │   ├─┬ minizlib@3.1.0
│ │   │ └── minipass@7.1.2 deduped
│ │   └── yallist@5.0.0
│ ├─┬ postcss@8.5.6
│ │ ├── nanoid@3.3.11
│ │ ├── picocolors@1.1.1
│ │ └── source-map-js@1.2.1 deduped
│ └── tailwindcss@4.1.14
└─┬ sharp@0.34.4
  ├── @img/colour@1.0.0
  ├─┬ @img/sharp-darwin-arm64@0.34.4
  │ └── @img/sharp-libvips-darwin-arm64@1.2.3 deduped
  ├─┬ @img/sharp-darwin-x64@0.34.4
  │ └── @img/sharp-libvips-darwin-x64@1.2.3 deduped
  ├── @img/sharp-libvips-darwin-arm64@1.2.3
  ├── @img/sharp-libvips-darwin-x64@1.2.3
  ├── @img/sharp-libvips-linux-arm@1.2.3
  ├── @img/sharp-libvips-linux-arm64@1.2.3
  ├── @img/sharp-libvips-linux-ppc64@1.2.3
  ├── @img/sharp-libvips-linux-s390x@1.2.3
  ├── @img/sharp-libvips-linux-x64@1.2.3
  ├── @img/sharp-libvips-linuxmusl-arm64@1.2.3
  ├── @img/sharp-libvips-linuxmusl-x64@1.2.3
  ├─┬ @img/sharp-linux-arm@0.34.4
  │ └── @img/sharp-libvips-linux-arm@1.2.3 deduped
  ├─┬ @img/sharp-linux-arm64@0.34.4
  │ └── @img/sharp-libvips-linux-arm64@1.2.3 deduped
  ├─┬ @img/sharp-linux-ppc64@0.34.4
  │ └── @img/sharp-libvips-linux-ppc64@1.2.3 deduped
  ├─┬ @img/sharp-linux-s390x@0.34.4
  │ └── @img/sharp-libvips-linux-s390x@1.2.3 deduped
  ├─┬ @img/sharp-linux-x64@0.34.4
  │ └── @img/sharp-libvips-linux-x64@1.2.3 deduped
  ├─┬ @img/sharp-linuxmusl-arm64@0.34.4
  │ └── @img/sharp-libvips-linuxmusl-arm64@1.2.3 deduped
  ├─┬ @img/sharp-linuxmusl-x64@0.34.4
  │ └── @img/sharp-libvips-linuxmusl-x64@1.2.3 deduped
  ├─┬ @img/sharp-wasm32@0.34.4
  │ └─┬ @emnapi/runtime@1.5.0
  │   └── tslib@2.8.1 deduped
  ├── @img/sharp-win32-arm64@0.34.4
  ├── @img/sharp-win32-ia32@0.34.4
  ├── @img/sharp-win32-x64@0.34.4
  ├── detect-libc@2.1.2
  └── semver@7.7.3

npm error code ELSPROBLEMS
npm error missing: @emnapi/core@^1.5.0, required by @tailwindcss/oxide-wasm32-wasi@4.1.14
npm error missing: @emnapi/wasi-threads@^1.1.0, required by @tailwindcss/oxide-wasm32-wasi@4.1.14
npm error missing: @napi-rs/wasm-runtime@^1.0.5, required by @tailwindcss/oxide-wasm32-wasi@4.1.14
npm error missing: @tybys/wasm-util@^0.10.1, required by @tailwindcss/oxide-wasm32-wasi@4.1.14

This is probably a question for the @tailwindcss/oxide-wasm32-wasi maintainers, or it might possibly be an npm bug.

[foobar-star]

I'll reach out to them to see about this issue. In the meantime can you confirm this is happening below and any possible explanation you might have for it to potentially aid the @tailwindcss/oxide-wasm32-wasi or NPM maintainers with the diagnosis of the issue on their end:

$ node -v
v24.10.0
$ npm -v
11.6.1
$ npx create-next-app@latest my-app -ts -tw -eslint (if these options do not work please just select typescript, tailwind, and eslint from the prompt)

$ npm ls -all | grep -i invalid
│ │ │ ├─┬ @napi-rs/wasm-runtime@0.2.12 invalid: "^1.0.5" from node_modules/@tailwindcss/oxide-wasm32-wasi
│ │   │ └── @napi-rs/wasm-runtime@0.2.12 deduped invalid: "^1.0.5" from node_modules/@tailwindcss/oxide-wasm32-wasi
npm error code ELSPROBLEMS
npm error invalid: @napi-rs/wasm-runtime@0.2.12 /project/workspace/my-app/node_modules/@napi-rs/wasm-runtime


$ rm -rf node_modules/sharp   
$ rm package-lock.json     
$ npm cache clean --force

$ npm install


$ npm ls -all | grep -i invalid
$

Also the latest stable version of node.js (for the next few days/weeks)

$ node -v
v22.10.0
$ npm -v
11.6.1

$ npx create-next-app@latest my-app -ts -tw -eslint
if flags are not working please select typescript, tailwind, and eslint


$ npm ls
my-app@0.1.0 /project/workspace/my-app
├── @emnapi/core@1.5.0 extraneous
├── @emnapi/runtime@1.5.0 extraneous
├── @emnapi/wasi-threads@1.1.0 extraneous
├── @eslint/eslintrc@3.3.1
├── @napi-rs/wasm-runtime@0.2.12 extraneous
├── @tailwindcss/postcss@4.1.14
├── @tybys/wasm-util@0.10.1 extraneous
├── @types/node@20.19.21
├── @types/react-dom@19.2.2
├── @types/react@19.2.2
├── eslint-config-next@15.5.5
├── eslint@9.37.0
├── next@15.5.5
├── react-dom@19.1.0
├── react@19.1.0
├── tailwindcss@4.1.14
└── typescript@5.9.3


$ npm ls -all | grep -i invalid
$ 
$ rm -rf node_modules/sharp 
$ rm package-lock.json
$ npm cache clean --force
$ npm install sharp --no-optional
$ npm ls            
my-app@0.1.0 /project/workspace/my-app
├── @eslint/eslintrc@3.3.1
├── @tailwindcss/postcss@4.1.14
├── @types/node@20.19.21
├── @types/react-dom@19.2.2
├── @types/react@19.2.2
├── eslint-config-next@15.5.5
├── eslint@9.37.0
├── next@15.5.5
├── react-dom@19.1.0
├── react@19.1.0
├── sharp@0.34.4
├── tailwindcss@4.1.14
└── typescript@5.9.3

$ npm ls -all | grep -i invalid
$

If not no worries but I am wondering if this might give a clue. Because the issues go away when removing sharp node_modules or removing sharp then installing sharp as a direct dependency with the -no-optional flag in node versions 22 and below.

[lovell]

My best guess would be that this might relate to the @tailwindcss/oxide-wasm32-wasi package bundling its dependencies and that some of these are also transitive, optional (filtered by cpu) dependencies of sharp.

https://github.com/tailwindlabs/tailwindcss/blob/acb27ef9e9229385ca0a30923be5d711b66cc90e/crates/node/npm/wasm32-wasi/package.json#L29-L44