Registry / devops / prettier-plugin-elm

prettier-plugin-elm

library0.12.0jsnpmunverified

Adds Elm language support to Prettier by wrapping elm-format. Version 0.12.0 (2025-09-21) requires Node >=18.20.6 and uses elm-format 0.8.8. Works with Prettier v2 (global) or v3 (local with explicit plugin config). Formats .elm files and Elm code blocks inside Markdown documents, with support for . Key differentiators: integrates elm-format directly into the Prettier ecosystem, handles both standalone files and embedded code blocks. Vendors elm-format internally, reducing version conflicts. Designed for Elm 0.19; older plugin versions support Elm 0.18. Maintained by giCentre, with TypeScript source code.

devops

npm install prettier-plugin-elm

github ↗package ↗

INSTALL

IMPORT

SIG · PRETTIER-PLUGIN-EL

prettier-plugin-elm

devopsjavascriptv0.12.0

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.

default

✓ const prettierPluginElm = require('prettier-plugin-elm');

✗ import prettierPluginElm from 'prettier-plugin-elm'; // ESM import will fail – plugin is CommonJS

The plugin does not export an ES module; use CommonJS require() or use Prettier's config resolution (plugins array).

prettierPluginElm in .prettierrc

✓ { "plugins": ["prettier-plugin-elm"] }

✗ Using plugins array without specifying package name or wrong casing

With Prettier v3, you must list the plugin explicitly in the config file; global install with v2 auto-detects.

CLI usage

✓ prettier --write '**/*.elm'

✗ Calling prettier with no plugin installed or using older elm-format version inline.

Run prettier directly on .elm files; the plugin is loaded automatically when installed globally (v2) or via config (v3).

Global installation with Prettier v2 and formatting a single file; also shows local config for Prettier v3.

// Install Prettier v2 globally and the plugin // npm install --global prettier@2 prettier-plugin-elm // // Now format an Elm file: // prettier --write Main.elm // Or for local project with Prettier v3: // npm install --save-dev prettier prettier-plugin-elm // Then in .prettierrc: { "plugins": ["prettier-plugin-elm"] } // Run: npx prettier --write src/**/*.elm

Debug

Known issues

breakingMinimum Node.js version increased to 18.20.6 in v0.12.0

fix

Upgrade Node.js to v18.20.6 or later.

affects: >=0.12.0

breakingNode.js v14 minimum required in v0.9.0, v12 in v0.8.0, v8 dropped in v0.6.0, v6 in v0.5.0

fix

Use older plugin version if running on legacy Node.js, or upgrade Node.

affects: <0.12.0

gotchaPrettier v3 does not support automatic plugin discovery; manual plugin listing is required.

fix

Add "plugins": ["prettier-plugin-elm"] to .prettierrc or Prettier config file.

affects: >=0.12.0

gotchaelm-format is vendored; installing separate elm-format globally may cause version mismatches.

fix

Do not install elm-format separately; the plugin uses its own bundled version.

affects: >=0.6.0

deprecatedPlugin assumes Elm 0.19; for Elm 0.18 use prettier-plugin-elm@0.3.

fix

Use version 0.3.x for Elm 0.18 compatibility.

affects: >=0.4.0

Errors

Common errors & fixes

Error: Cannot find module 'prettier-plugin-elm'

Plugin not installed or not in node_modules.

fix

Run 'npm install --save-dev prettier-plugin-elm' (local) or 'npm install --global prettier-plugin-elm' (global).

Error: [prettier-plugin-elm] Could not find elm-format.

The vendored elm-format binary is missing or corrupted.

fix

Reinstall the plugin: npm install prettier-plugin-elm. Ensure network access for binary download.

Error: [prettier-plugin-elm] elm-format timed out

Elm file formatting took longer than expected; possibly large file or infinite loop.

fix

Increase timeout via PR or reduce file size. Check elm-format version compatibility.

Error: Plugin loaded but no parser found for '.elm'

Prettier v3 without explicit plugin listing.

fix

Add "plugins": ["prettier-plugin-elm"] to .prettierrc.

Upgrade

Version history

0.12.0latest on npm

Audit

Dependencies

prettierrequiredPeer dependency required at runtime for formatting orchestration.

elm-formatrequiredVendored dependency for actual Elm formatting logic; not a peer dependency.

Agent activity

4 hits · last 30 days

node

Resources

githubhttps://github.com/gicentre/prettier-plugin-elm ↗

packagehttps://www.npmjs.com/package/prettier-plugin-elm ↗