What / Why

Currently running npm install fetches and installs a package as-is. However it would be more flexible to be able to specify a patch to apply at installation time to customize a package. One use case is to modify the package source to remove donation banners in install logs.

This is complementary to -- and more general than -- #80.

When

At install time, with the presence of a new flag.

How

Add a --patch /path/to/my.patch option to npm install. NPM would then fetch the source as usual, run patch -p0 < /path/to/my.patch to apply the customization, and continue with the normal installation process.

Example

Suppose you want to install core-js without its donation banner breaking your continuous integration. You can already use npm install --loglevel silent, but this will silence other potentially useful messages.

Instead, the user could create a patch file, e.g. nobanner.patch:

--- packages/core-js/postinstall.js
+++ packages/core-js/postinstall.js
@@ -52,5 +52,3 @@
   // eslint-disable-next-line no-console,no-control-regex
   console.log(COLOR ? BANNER : BANNER.replace(/\u001B\[\d+m/g, ''));
 }
-
-if (isBannerRequired()) showBanner();

Then, using the proposed feature, run:

npm install --patch nobanner.patch core-js