Development setup

If you want to help contribute to Premail's development, great! (If you just want to learn how to install and use Premail, head over here.)

Clone Premail's GitHub repo:

git clone https://github.com/premail/premail

Run node --version to determine your release of Node and install if necessary.

Node versions

Premail requires Node version 12.x or 14.x. See Premail setup for more.

In your local copy of the Premail repo, run:

npm install

Editor plugins

MJML has plugins for Visual Studio Code, Atom, and Sublime Text 3 and 4 that will help with things like syntax highlighting.

Testing your work

As you develop, you'll want to test that the premail command is still working. To do this, set up a separate directory outside of your local copy of the Premail repo, for instance called test. Then use npm link to reference your local version of Premail, rather than the current npm version.

Alternatively, use npm install -g . within your local Premail repo (you'll need to uninstall Premail globally first). This is actually what Premail does in a GitHub Action to make sure each commit doesn't break basic functionality.

The commands premail init and premail destroy --yes --readme are helpful in quickly setting up and tearing down test projects. If you change anything in the src/scaffolding/project directory, for instance, you'll need to destroy and recreate a project in order to pick up those changes.