npm - How can I specify the required Node.js version in package.json?

Question

I have a Node.js project that requires Node version 12 or higher. Is there a way to specify this in the packages.json file, so that the installer will automatically check and inform the users if they need to upgrade?

Answer 1

I think you can use the "engines" field:

{ "engines" : { "node" : ">=0.12" } }

As you're saying your code definitely won't work with any lower versions, you probably want the "engineStrict" flag too:

{ "engineStrict" : true }

Documentation for the package.json file can be found on the npmjs site

Update

engineStrict is now deprecated, so this will only give a warning. It's now down to the user to run npm config set engine-strict true if they want this.

Update 2

As ben pointed out below, creating a .npmrc file at the root of your project (the same level as your package.json file) with the text engine-strict=true will force an error during installation if the Node version is not compatible.