Forever ago (in Internet time), the developer(s?) of Pocket Casts released an update with some really humorous release notes:
As I do, I got thinking about how I felt about it. While my initial reaction was to be amused, I quickly turned to finding it unhelpful. In fact, most apps have awful release notes. My least favorite phrase, which seems to appear in the release notes of every updated app on my phone, is “and bug fixes.”
Despite the title of this post, there’s no one right way to write release notes. The “right” way depends on what you’re releasing, for one. In a Linux distribution like Fedora, release notes could be composed of the release notes for every component package. However, that would be monumentally unwieldy. Even the Fedora Technical Notes — which report only the changed packages, not the notes for those packages — is not likely to be ready by too many people. The Release Notes are a condensed view, which highlight prominent features. The Release Announcement is even further condensed, and is useful for media and public announcements. This hierarchy is a good example of the importance of the audience.
I’ve seen arguments that release notes are unnecessary if the source code repository is accessible. Who needs release notes when you can just look at the commit log? This is a pretty lousy argument. A single change may be composed of many commits and a single commit may represent multiple changes (though it shouldn’t). Not to mention that commit messages are often poorly written. I’ve made far too many of those myself. Even if the commit log is a beautiful representation of what happened, it’s a lot to ask a consumer of your software to scour every commit since the last release.
My preference for release notes includes, in no particular order, a list of new features, bugs fixed, and known issues. The HTCondor team does a particularly good job in that regard. One thing I’d add to their release notes is an explicit listing of the subsystem(s) affected for each point. The exact format doesn’t particularly matter. All I’m looking for is an explanation as to why I should or should not care about a particular release. And “fixed some bugs” doesn’t tell me that.