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Mill is a build tool developed by Li Haoyi in order to create something simpler and more intuitive than most of the other build tools today. There is extensive documentation on the Mill website.

Automatic installation#

The first time you open Metals in a new Mill workspace you will be prompted to import the build. Select "Import Build" to start the automatic installation. This will create all the needed Bloop config files. You should then be able to edit and compile your code utilizing all of the features.

To force a Mill version you can write it to a file named .mill-version in the workspace directory.

Manual installation#

Manual installation is not recommended, but it's pretty easy to do. There are only two steps involved.

First add one import line to your file or in any other file it depends on:

import $ivy.`com.lihaoyi::mill-contrib-bloop:VERSION`

Remember to replace the VERSION with your Mill version.

After adding the line you should be able to generate the Bloop config files needed to work with Metals using the below command:

mill mill.contrib.Bloop/install

Afterwards, you can just open Metals and start working on your code.