Asynchronous package upgrades with Paradox

Two months ago, I listed a few big things I was looking forward to for Emacs 25. I knew I was being unrealistically optimistic to mention concurrency in Elisp, but there was a point behind it. It bothered me a lot that I had to get up and go for a coffee whenever I upgraded more than a few packages, and asynchronous upgrades were the only way I saw of fixing that. This Christmas, as promised and well ahead of schedule, I've implemented asynchronous execution into Paradox, thanks to the fantastic async library.

What this means is that whenever you hit x on Paradox's Package Menu, be it an upgrade, installation, or deletion, if you've installed the async library, you'll have the option to perform the operation in the background. Then you can get back to work and forget about it. Paradox will message you once it's done, and that's it.

You can customize whether or not you want this feature with the paradox-execute-asynchronously variable (the default is to ask you each time). It is still considered a beta feature, so you won't find it on Melpa-stable yet. You can get it on Melpa or wait a couple of weeks for it to be marked stable.

As a bonus, there's also a new command paradox-upgrade-packages, inspired by this Emacs.SE question, which upgrades everything without the usual manual labor.