Any projects we do where npm packages are a dependency inevitably end up with frequent transient build failures. npm install will kick out with some warning or error that's buried well past the 4MB log limit from CircleCI. Rebuilding the project always works.

I haven't been able to determine if this is an NPM issue or CircleCI issue, but short research periods seem to indicate the former, and I find the availability of packages in the manager to be 'unreliable'. That's not really something that I want to deal with in software that is managing my dependencies, but that's the state of the world. Apt repositories have a tendency to do the same thing, actually.