Starting today, if you type `npm install npm@latest -g`, you’ll be updated to npm version 5. In addition, npm@5 is bundled in all new installations of Node.js 8, which has replaced Node.js 7 in the Node Project’s current release line.
(Installing the npm website on our own dev environments went from 99 seconds using npm@4 to 27 seconds with npm@5. Now we spend less time jousting.)
Shrinkwrap has been a part of npm for a long time, but npm@5 makes lockfiles the default, so all npm installs are now reproducible. The files you get when you install a given version of a package will be the same, every time you install it.