How do I get notified of _all_ package updates? [duplicate]

Is there a mailing list and/or IRC channel that announces changes to packages hosted by the Canonical repositories? If so, how does one subscribe?

Here's an update explaining how this question is different from those linked as possible duplicates:

I'm interested in subscribing to all changes in all packages throughout a given repository-suite tuple. Some editors/commenters have shown how to subscribe to events relevant to a single package, but the technique relies on setting up delta tracking of websites, either via browser extension or cronjob-python-script. This technique has a number of shortcomings that make it unsuitable for what I want:

• it polls rather than subscribes; i.e., polling too fast wastes bandwidth and polling too infrequently risks losing information
• it's too manual; i.e., it requires a human subscriber to add the things being monitored
• it's too shallow; i.e., it does not track or accumulate changes through time

To those asking "Why?", let me explain my motivation by way of example. Consider an automated nightly build process that, without any change to the package being built, suddenly starts failing. Clearly, something in the Build-Depends and/or Depends has changed to cause the failure. One can bound the duration between the most recent success and the failure that follows it. What happened to the package repositories within that duration?