It appears this is a directory full of software updates, and I can probably safely delete all but the most recent one (maybe even the most recent one as well). On the other hand, this probably shouldn’t happen at all?
I’ve seen an open Issue for this. Squirrel (the installer/updater software) is supposed to clean this out and only keep two historic copies (plus one for the latest version). Sometimes if the permissions are set up strangely this doesn’t occur.
There’s this open Issue, though it is marked as OS X-specific:
On Windows it does happen with the installation directory as well.
It cleans up some versions, but rarely all and it seems quite random which ones.
Pre-1.0 I used to clean this folder up manually on occasion.
Damn, that was annoying as hell!
Got same issue (although mine was 15gb), just went ahead and deleted the folders. Restarted Atom, all fine. The update even finally worked!
GitHub client also uses ship it, folder had just 200mb or so, I also deleted it, with GitHub still running.
In case anyone’s wondering, I doubt there’s any trouble in wiping them.