Elm Dev

npm install -g elm-dev

Elm Dev is an Elm compiler with:

• Language Server Protocol (LSP) support
• Model Context Protocol (MCP) support
• Hot reloading
• VS Code/Cursor plugin
• A full app framework

Install in VS Code / Cursor

• Open the Extensions view and install the Elm Dev extension.

Make sure you have elm-dev installed globally, or have set the path in the extension settings.

MCP Setup in VS Code/Cursor/Claude Code

To use the elm-dev mcp, you just need your agent to run elm-dev mcp.

In Cursor, this means creating ~/.cursor/mcp.json with:

{
  "mcpServers": {
    "elm-dev": {
      "command": "elm-dev",
      "args": ["mcp"]
    }
  }
}

CLI help

Welcome to Elm Dev

  elm-dev init ...................... Create a new Elm project
  elm-dev make [module] ............... Build your Elm project
  elm-dev install [author/project] ......... Install a package

Add to your Elm app:

  elm-dev add page <url> ...................... Add a new page
  elm-dev add store <name> ................... Add a new store
  elm-dev add effect <name> ................. Add a new effect
  elm-dev add listener <name> ............. Add a new listener

Move an elm-dev-generated file into your project:

  elm-dev customize <module> .... Customize project components

Testing:

  elm-dev test .......... Discover, compile, and run Elm tests
  elm-dev test init ............................ Setup testing
  elm-dev test install <author/project> ..... Install test dep